Meta released Muse Spark 1.3 on September 2, 2026, four weeks after Muse Spark 1.2 and Muse Code. I am writing this a few days later with the same builder lens I used for that post, Grok 4.6, and GPT-6 Astra vs Gemini 3.8 Flash: not who won the internet, but what I would put on a long agent loop for product and agency work.
The important framing is that this is a model increment on an existing harness, not another Muse Code launch. 1.3 drops into Muse Code and the Meta Model API the same day. Max reasoning, the setting behind many of Meta’s strongest rows, stayed behind a safety gate at launch and is now live in both products.
Muse Spark 1.3 is a coding and agent update to 1.2. Context stays at 1M tokens. Inputs are text, image, and video. Access is Muse Code, the Meta Model API, and OpenRouter as meta/muse-spark-1.3 (Standard) and meta/muse-spark-1.3-contributor. Treat it as a hosted proprietary model: no downloadable weights in this release. Meta’s roadmap still lists bigger models and a Muse Spark open-weights drop, with no date.
Muse Code is still a terminal agent for macOS and Linux, installed with curl -fsSL https://dev.meta.ai/install.sh | bash. There is still no dedicated desktop app and no Cursor picker row. On Windows, that remains the same workflow gap I wrote about for 1.2: my daily shipping loop lives in Cursor on this machine, not a Linux terminal agent.
Meta says 1.3 was trained on more long-horizon coding tasks and is easier to use in common engineering workflows: fewer turns where they are not needed, less verbose, cleaner coding style. Internal comparisons by Meta engineers claim about 20% fewer tool calls and 25% fewer tokens than 1.2 on those jobs.
The UX story this time is the model, not a new shell.
Collaboration instead of silent drift. Meta trained 1.3 to ask clarifying questions when the prompt is ambiguous, ask for help when it is stuck, and confirm before consequential actions. On long jobs it can either send frequent updates or work quietly, depending on how you steer it.
Messy single-thread work. It is supposed to map a new prompt to the right task inside one long conversation, even when you interrupt or steer an older request. That is the failure mode that burns real agent days: two jobs get fused, a constraint gets dropped, and the model keeps going.
Max vs xhigh. xhigh shipped on day one. Max waited about two days for extra safety testing and is now available in Muse Code and the Meta Model API. Artificial Analysis’s September 2 note still treated max as a limited partner preview. That lag matters when you read launch tables: several of Meta’s headline rows are max, not the mode you could call on September 2.
Safety posture. Meta claims stronger resistance to adversarial inputs and prompt injections, plus better calibration on irreversible actions. That does not replace your own approval gates. It is the baseline I want from a tool-using coding model.
Compared with 1.2: same Muse Code runtime (persistent background agents, append-only event log, isolated worktrees, /plan /grill /goal). The increment is judgment, token waste, long-context retrieval, and a higher reasoning ceiling.
Early September compressed three closed US moves into three days. I already wrote the Astra vs 3.8 Flash comparison in GPT-6 Astra vs Gemini 3.8 Flash. Muse is the third name on that calendar, not a side note.
Western labs are still competing on closed cadence. This week the cheap workhorse was Google’s Flash, the gated flagship was Astra, and Meta’s move was a four-week coding-agent bump at the same $1.25 / $4.25 sticker as 1.2.
Meta’s methodology and the Muse Spark 1.3 model page compare 1.3 (max) with 1.2 (xhigh), GPT-5.6 Sol (max), and Claude Opus 5 (max). These are not one shared harness. Coding rows mix native agent products and mini-swe-agent. Knowledge-work rows use each benchmark’s own setup.
| Benchmark | Spark 1.3 (max) | Spark 1.2 (xhigh) | GPT-5.6 Sol (max) | Opus 5 (max) |
|---|---|---|---|---|
| Terminal-Bench 2.1 | 88.8% | 82.9% | 88.8% | 86.7% |
| DeepSWE v1.1 | 75.4% | 55.0% | 73.0% | 74.0% |
| SWEAtlas CodeBase QnA | 59.4% | 46.2% | 53.5% | 52.7% |
| MRCR 256K-512K | 98.5% | 66.3% | 91.5% | n/a |
| MRCR 512K-1M | 98.1% | 55.5% | 73.8% | n/a |
| GDPVal-AA v2 | 1754 | 1615 | 1710 | 1824 |
| JobBench | 64.9 | 61.6 | 45.4 | 65.7 |
| OSWorld 2.0 (partial) | 66.9 | 47.6 | 62.7 | 68.3 |
On Meta’s own table, 1.3 leads coding and long context. It ties Sol on Terminal-Bench, leads DeepSWE and SWEAtlas, and jumps MRCR from the mid-50s/60s into the high 90s. Opus 5 still leads knowledge work and computer use: GDPVal, JobBench, OSWorld, and AutomationBench. Sol takes DeepSearchQA (93.0 vs 89.4) and Meta’s internal Agentic IF Index (60.5 vs 57.8).
That is a different story from 1.2, where Muse sat just behind Opus on terminal and repo loops. The 1.3 coding rows flipped. The knowledge-work rows did not.
Artificial Analysis scored Muse Spark 1.3 (xhigh) at 61 on the Intelligence Index, up 4 points from the 1.2 listing in that same note (57, August) and 8 points from 1.1 (53, July). That ties GPT-5.6 Sol (max), Grok 4.6 (high), and Claude Opus 5 (high). It sits behind Claude Fable 5.1 (max, 66), Claude Opus 5 (max, 63), and Claude Fable 5 (max, 62).
Muse Spark 1.3 (max) lands at 62, helped by Tau3-Bench Banking (52%, #1 among models AA has scored vs 47% for xhigh) and GDPVal-AA v2 (1754 Elo vs 1709 for xhigh). AA measured max using 62% more reasoning tokens on GDPVal and 28% more on Tau3-Bench Banking than xhigh. The extra point is not free.
The gain is concentrated in agentic work. Versus 1.2, xhigh moves Tau3-Bench Banking from 35% to 47%, Terminal-Bench v2.1 from about 80% to 85%, and GDPVal-AA v2 from 1615 to 1709 Elo. Scientific rows also rose: CritPt 18% to 26%, GPQA Diamond 90% to 94%. Two regressions: AA-LCR dropped 4 points (83% to 79%), and AA-Omniscience accuracy fell because 1.3 abstains more often, which also cut hallucinations.
Cost per Intelligence Index task is $0.55 at Meta’s unchanged $1.25 / $4.25 pricing. That is the lowest AA lists for any model at 59 or above. Direct peers at 61 cost more: Grok 4.6 high about $0.94, Sol max about $0.95, Opus 5 high about $1.23. Gemini 3.8 Flash high sits nearby at 59 and $0.58. 1.3 is still more expensive per task than 1.2’s $0.40, because agentic evals used about 57% more input tokens. AA had no public max pricing at launch.
Reading both tables as a builder: Muse is now a frontier closed coding wedge at a mid-range sticker, not a near-miss. Flash and K3 still own different open-price niches. Grok 4.6 still owns the Cursor-native seat. Fable 5.1 still owns the composite index.
On coding specifically, the practical split looks like this:
Meta did not cut the sticker. Both published tiers keep the 1M context window. Max does not have a separate public rate card.
| Tier | Input / 1M | Cached input / 1M | Output / 1M | Data use |
|---|---|---|---|---|
| Standard | $1.25 | $0.15 | $4.25 | Meta says not used to improve products |
| Contributor | $0.10 | $0.002 | $0.20 | Prompts and completions used to train / improve Meta products |
OpenRouter lists the same Standard card on meta/muse-spark-1.3. Contributor is meta/muse-spark-1.3-contributor. Rough worked example, unchanged from 1.2: 1M uncached input plus 100K output is about $0.12 on Contributor and about $1.68 on Standard. Cache hits collapse that further. AA’s $0.55 per Index task is the more useful agent number: 1.3 thinks longer than 1.2, so the same sticker can still raise the bill.
Honest status: Muse Spark 1.3 is not in the Cursor model picker today. OpenRouter lists it, so a custom provider is a possible experiment. My daily IDE stack still stays on Composer, Grok, and the other models Cursor already exposes. That is where I already ship this site (Building this blog with Cursor and Grok 4.5, Grok 4.6).
What I want next is the same as 1.2: Cursor adds Muse Spark (directly or via OpenRouter) so I can run the same multi-file IDE loop I use for client work, without leaving the editor for a macOS/Linux terminal agent. Until that lands, the test path is Meta Model API or OpenRouter for API experiments, and Muse Code CLI only if I am on a supported OS.
If Cursor ships it, the first thing I will do is the same delivery test I use for every release: one real multi-file task with tools, constraints, and a deadline.
When I would reach for Muse Spark 1.3 / Muse Code
When I would still pick something else
Muse Spark 1.3 is the first Muse release I would shortlist against Claude Code and Codex on coding and long context, not only on price. Independent AA puts xhigh at 61 and max at 62, cheapest in that intelligence cluster at $0.55 per Index task, with max now live after a two-day safety gate. It is still not a verified takeover of Fable 5.1, still closed weights, and still missing from Cursor. Watch independent Terminal-Bench verification, keep Contributor data terms in mind, and hope the picker catches up so the delivery test can happen inside the editor.
Leaderboards help you shortlist. Delivery decides.
If you want help picking a model stack that still ships under real usage and cost constraints, start on the contact page.
OpenAI released GPT-6 Astra on September 3, 2026, to a limited set of organizations, with Plus, Pro, Business, Enterprise, API, and AWS access rolling out over the following days. Google had already shipped Gemini 3.8 Flash on September 2, generally available, at the same introductory Flash sticker as 3.7 Flash.
I am writing this the next day with the same builder lens I used for GLM-5.3, DeepSeek V4 Pro 0813, and Grok 4.6: not who won the internet, and not whether this is “AGI,” but what I would put on a long agent loop and how the bill looks when that loop runs all week.
These are two different products that happened to land 24 hours apart. Astra is a $10 / $50 computer-use flagship that succeeds GPT-5.6 Sol, with a gated cyber jump behind OpenAI Daybreak. 3.8 Flash is Google’s third Flash release in six weeks, multimodal, GA today, and priced like a workhorse while approaching frontier on long-horizon coding. Claude Fable 5.1 shipped on September 1 and remains the closed-coding reference, not the third subject of this post.
| Spec | GPT-6 Astra | Gemini 3.8 Flash |
|---|---|---|
| Lab | OpenAI | Google DeepMind |
| Release | September 3 (limited), wider rollout following days | September 2, GA |
| Model id | gpt-6-astra |
gemini-3.8-flash |
| Context | 1,050,000 tokens | 1,048,576 tokens |
| Max output | 128,000 | 65,536 |
| Inputs | Text, computer use, tools | Text, image, audio, video |
| Output | Text | Text |
| Reasoning | Effort levels; none unsupported |
LOW / MEDIUM / HIGH (default MEDIUM; MINIMAL gone) |
| Knowledge cutoff | April 30, 2026 | March 2026 (AA listing) |
| Access today | Trusted Access / staged ChatGPT and API | Gemini API, AI Studio, Antigravity, Gemini Enterprise, Gemini app |
| API sticker | $10 in / $50 out per 1M | $0.75 / $3.75 intro through December 31 |
Astra is available as gpt-6-astra in the OpenAI API and on Amazon Bedrock. Enterprise admins enable it per workspace; it is off by default at launch. Pro, Business, and Enterprise plans also get GPT-6 Astra Pro. Fast mode is up to 2x Standard speed at 2x Standard price. Fast mode is unavailable with EU data residency.
3.8 Flash is the Gemini 3 family workhorse between Pro and Flash-Lite. Google Cloud docs list the same 1M window as 3.7 Flash, the same output cap, and the same thinking-level enum. Thinking tokens bill as output. Google says the model works harder on complex jobs: extra reasoning steps, iterative tool calls, and more tokens at higher effort. If compute efficiency is the constraint, Google still points you at 3.7 Flash.
Early September compressed three closed US moves into three days.
Google’s own framing for 3.8 Flash is cadence: 3.7 Flash was August 13, covered in the GLM-5.3 post, and 3.8 is the third Flash in six weeks at the same intro price. Western labs are still competing on closed cadence and intro discounts. This week the discount sat on Google’s workhorse, while OpenAI moved the flagship sticker up.
Artificial Analysis on Astra and the 3.8 Flash note are the like-for-like source. These are AA Intelligence Index v4.1.1, not OpenAI’s launch table.
| Model | Intelligence Index | Cost per Index task |
|---|---|---|
| Claude Fable 5.1 (max, with fallback) | 66 | Premium closed |
| GPT-6 Astra (max) | 61 | $7.7 |
| GPT-5.6 Sol | 61 | Lower than Astra at max |
| Gemini 3.8 Flash (high) | 59 | $0.58 |
| Gemini 3.8 Flash (medium) | 57 | $0.41 |
| Gemini 3.7 Flash (high) | 56 | $0.40 |
| Gemini 3.8 Flash (low) | 52 | $0.24 |
Astra ties Sol at 61 and sits five points behind Fable 5.1. AA’s other headline for Astra is the Coding Agent Index: 67 in Codex, about even with Fable 5 and Opus 5, behind Fable 5.1 at 70, at less than half Fable 5’s cost per coding-agent task because Astra used about one third of Sol’s tokens in that harness.
Flash gained three Intelligence Index points over 3.7 Flash. AA says that jump is mostly agentic: Terminal-Bench v2.1, GDPval-AA v2, and a 12-point gain on τ³-Banking to 45%. It lands on the Intelligence vs cost Pareto frontier at $0.58 per Index task. That is still about 13x cheaper than Astra’s $7.7, and about 40% more per task than 3.7 Flash because 3.8 Flash burns ~30% more output tokens (~48k per Index task) and takes more agentic turns.
Astra’s Intelligence Index story is the inverse. AA measured ~10% fewer output tokens than Sol at max, then a 2.5x sticker increase that makes Astra about 75% more expensive per Index task than Sol. Token efficiency went up. The bill still went up. AA also flags mixed knowledge-work progress: hallucination rate on AA-Omniscience dropped from 92% to 51% at max, AA-Briefcase Elo jumped ~80 points, and GDPval-AA v2 dropped ~80 Elo.
OpenAI’s own launch table lists AA Intelligence Index v4.1.1 as Astra 61.2, Sol 60.9, Fable 5.1 65.7, and Gemini 3.8 Flash 58.7. Close to AA’s rounded page. I am using AA’s published 61 / 59 / 66 as the independent scorecard.
This is Astra’s actual product. OpenAI’s launch table, max effort, vendor harness:
| Benchmark | GPT-6 Astra | Closest closed | Gemini 3.8 Flash |
|---|---|---|---|
| OSWorld 2.0 (offline set) | 72.6% (~40 min/task) | Sol 65.7% (~75 min); Opus 5 70.2% | n/a in that table |
| Agents’ Last Exam | 59.3% | Opus 5 55.5%; Sol 53.6% | n/a |
| ScreenSpot-Pro (no tools) | 92.7% | Fable 5 87.3%; Sol 76.9% | n/a |
| AutomationBench | 41.4% | Fable 5.1 31.4%; Sol 18.1% | n/a |
| BenchCAD (with tools) | 95.9% | Fable 5.1 84.3%; Sol 83.3% | n/a |
| BrowseComp | 91.5% | Sol 90.4%; Opus 5 90.8% | n/a |
OSWorld is the row I would actually act on. Higher accuracy and about 47% less wall time than Sol is the difference between an agent you babysit and one you can hand a desktop job. OpenAI also says the updated Codex harness plus Astra is 1.9x faster than the current Sol experience on Mind2Web.
3.8 Flash is not absent from professional work. Google’s launch post puts it ahead of 3.7 Flash and “other frontier models” on Vals Finance Agent V2 and Harvey’s Legal Agent Benchmark, and at 54.9% on HLE-Verified. Those are vendor claims without a side-by-side number against Astra in the same table. Treat them as Google’s knowledge-work pitch, not as a bake-off.
Two Terminal-Bench versions are in circulation this week. Do not mix them.
Google Cloud’s developer guide (vendor, 3.8 vs 3.7):
| Benchmark | 3.8 Flash | 3.7 Flash |
|---|---|---|
| Terminal-Bench 2.1 | 90.8% | 81.6% |
| SWE-Bench Pro | 61.6% | 60.4% |
| SWE-Atlas | 51.9% | 48.0% |
| τ³-bench Banking | 38.1% | 30.9% |
| Humanity’s Last Exam | 45.4% | 45.7% |
OpenAI’s launch table (vendor, including Flash):
| Benchmark | GPT-6 Astra | GPT-5.6 Sol | Fable 5.1 | Gemini 3.8 Flash |
|---|---|---|---|---|
| Terminal-Bench 4.0 | 57.9% | 37.3% | 55.8% | 19.1% |
| DeepSWE v1.1 | 74.1% | 72.7% | 67.4% | 73.8% |
| FrontierCode 1.1 Main | 53.3% | 47.5% | 50.9% | 43.6% |
| GPQA Diamond | 96.0% | 94.6% | 93.7% | 95.3% |
| HLE with tools | 57.2% | n/a | 65.0% | n/a |
| FrontierMath Tier 4 v2 | 97.6% | 83.0% | 87.8% | n/a |
| ARC-AGI-3 | 99.9% | 7.8% | n/a | n/a |
Reading that as a builder: DeepSWE is a near tie. Astra 74.1, Flash 73.8, Opus 5 73.7. Long-horizon repo work is not why you pay Astra’s sticker. Computer use, Terminal-Bench 4.0, AutomationBench, and template-faithful professional artifacts are.
Flash’s 90.8% on Terminal-Bench 2.1 versus Astra’s 57.9% on Terminal-Bench 4.0 is a version split, not a knockout. OpenAI’s own Flash row on TB 4.0 is 19.1%. That is model plus harness plus board, not “Flash cannot use a terminal.”
HLE with tools still belongs to Fable 5.1 at 65.0%. Astra at 57.2% is not a clean reasoning sweep. Google Cloud’s HLE row for Flash is 45.4%, basically flat versus 3.7 Flash at 45.7%. Coding and tool use moved. The old knowledge exam did not.
ARC-AGI-3 at 99.9% is the number to read last. OpenAI’s footnote says it used the Responses API harness. Independent recaps of ARC Prize runs put stateless API calls much lower, in a roughly 17% to 63% band depending on reasoning tier, with the marketed figure needing a stateful adapter and an expensive comprehensive run. If you call gpt-6-astra statelessly, do not budget for 99%.
Official API rates to budget against (input / output per 1M tokens). Verify before you quote a client.
| Model | Input | Output | Notes |
|---|---|---|---|
| Gemini 3.8 Flash intro | $0.75 | $3.75 | Through December 31, 2026. Then $1.50 / $7.50 |
| Gemini 3.8 Flash cache read | $0.075 | n/a | 90% off input at intro |
| GPT-6 Astra | $10 | $50 | Cache reads 90% off ($1). Cache writes 25% premium ($12.50) |
| GPT-6 Astra Fast | ~$20 | ~$100 | 2x Standard price, up to 2x speed |
| GPT-5.6 Sol (promo) | $4 | $20 | AA and launch-week recaps. August posts still had $5 / $30 |
| Claude Fable 5.1 | $10 | $50 | Cache reads now $0.25, 75% below Fable 5 |
| Grok 4.6 | $2 | $6 | Unchanged from the Grok 4.6 post |
Astra matches Fable 5.1’s uncached sticker and sits 2.5x above Sol’s current promo. Flash kept 3.7 Flash’s intro rate. The per-token gap is not the whole bill. 3.8 Flash uses more tokens than 3.7 Flash. Astra uses fewer tokens than Sol and still costs more per AA Intelligence Index task.
Worked examples at current intro / Standard rates (approximate, thinking tokens ignored unless noted):
That last row is the same order of magnitude as AA’s $7.7 vs $0.58 per Intelligence Index task. On January 1, 2027, Flash doubles and that $0.59 trace becomes about $1.18. Still cheap next to Astra. Not the 2026 intro sticker you can quote into next year.
Both labs shipped a public workhorse and a gated cyber path in the same window. I am staying at published boards and access gates.
Astra meets the Critical threshold in cybersecurity under OpenAI’s Preparedness Framework. OpenAI’s launch table, without production safeguards on the exploit boards: ExploitBench 100% vs Sol 78.5%; ExploitGym 42.4% vs Sol 30.3%; a contamination-controlled ExploitBench (June-August 2026) at 39.0% vs Sol 11.5%; SRE-Bench 88.0% pass@1 vs Sol 55.9%. The production model launching this week does secure code review and patching, and refuses proof-of-concept exploit creation. OpenAI says Daybreak will expand defender workflows (validation, malware analysis, detection engineering) with less restrictive safeguards in the coming weeks. Extra safety checks can pause a ChatGPT or Codex task for review, or stop an API task outright.
NBC’s recap is the public-risk framing I care about for client work: Astra can find previously unknown flaws and develop exploits across well-protected systems without a person guiding each step, which is exactly why the gates exist. OpenAI also reports fewer misaligned computer-use outcomes than Sol (3.4% vs 18.8% in one internal realistic-work eval without confirmation policy) and a CoT monitorability regression it names as a research priority.
Gemini 3.8 Flash Cyber is a separate model, not a mode on gemini-3.8-flash. It is Fairwind-only: trusted government authorities, critical infrastructure operators, and software maintainers. Google says it prioritized patching over exploitation. Vendor claims: frontier-level CyberGym discovery; an internal 20-language discovery set above 70%; CWE-Bench pass@1 47.2% vs a leading frontier model at 47.8% at much lower cost; Chrome Security produced 2.6x more correct patches than the best larger commercial models they compared. Public 3.8 Flash keeps tighter CBRN and cyber-offense safeguards. Flash Cyber does not.
When I would reach for GPT-6 Astra
When I would reach for Gemini 3.8 Flash
LOW / MEDIUM / HIGH) when you want to trade tokens for latency on the same model idWhen I would still pick Fable 5.1, Grok 4.6, or DeepSeek
GPT-6 Astra is the expensive computer-use flagship: better OSWorld and professional-work rows than Sol, near-tied with Flash on DeepSWE, behind Fable 5.1 on the Intelligence Index and HLE with tools, and gated on the cyber jump that triggered OpenAI’s Critical threshold. Gemini 3.8 Flash is the workhorse that kept the 3.7 intro sticker, climbed to 59 on AA, and sits on the cost Pareto frontier while burning more tokens than 3.7 Flash by design.
I would shortlist Flash as the default volume agent this week. I would shortlist Astra when the job is actually driving a computer, shipping a finished artifact, or replacing Sol in an OpenAI-standardized stack. Leaderboards help you shortlist. Delivery decides. Try the same test I use for every release: one real multi-file task with tools, constraints, and a deadline.
If you want help picking a model stack that still ships under real usage and cost constraints, start on the contact page.
The week of August 16 to 22 was not a flagship drop. GLM-5.3 already had its bake-off on the 19th. What stacked up was infrastructure and distribution. Stripe agreed to buy the routing layer most agencies already treat as a utility. Cursor shipped a Git host. OpenAI refreshed ChatGPT onto GPT-5.6 August snapshots and cut Sol API prices. DeepSeek hung vision off V4-Flash as an experiment. Etched raised again, to $21 billion. Slack put coding agents in channels. Nevada said yes to thousands of robotaxis, which is deployment news, not a coding-stack change.
I am writing this on Saturday, August 22, 2026, with the same builder lens I used for DeepSeek V4 Pro 0813, V4 Flash, Kimi K3, and Grok 4.6: not who won the internet, but what I would put on a long agent loop and how the bill looks when that loop runs all week.
The models you already shortlisted did not get replaced. The pipes around them did.
| Date | What | Why a builder cares |
|---|---|---|
| Aug 17-18 | Cursor Origin early beta, covered as GitHub’s week went sideways | Native repos and PRs inside Cursor, with GitHub still the source of truth for anything started there |
| Aug 18 | Etched raises $700 million at $21 billion, led by Jane Street | Cluster-scale frontier inference, not a single-model ASIC you swap this week |
| Aug 19 | Stripe agrees to acquire OpenRouter | The multi-model gateway a lot of production traffic already hits, plus Stripe Token Billing in the same house |
| Aug 19 | GPT-5.6 August into ChatGPT; Sol API pricing | Consumer snapshot refresh, not a new generation. 20% input and 33% output cut on Sol |
| Aug 20 | Slack Code | Tag a coding agent, get a project channel with diffs, plan, and a live HTML preview |
| Aug 20 | Nevada robotaxi permits | Tesla, Waymo, and Uber get Clark County caps. Deployment news, not a coding-stack change |
| Aug 21 | deepseek-v4-flash-vision-exp |
Experimental vision on V4-Flash rates. Same-day Harness 0.1.1 and a free Files API |
I am not treating Gemini 3.7 Flash as this week’s news. It GA’d on August 13. The intro price is still live, so it sits in a kicker at the end, not in this table.
On August 19, Stripe said it had agreed to acquire OpenRouter. Primary writeup: Stripe’s newsroom note. Payments-industry recap: Payments Dive.
OpenRouter is the AI model gateway that routes across 400+ models from 80+ providers. If you have shipped an agent that needed a fallback when one lab rate-limited you, you already know why this company exists. Stripe already sells Token Billing. Putting the router next to the meter is the whole thesis.
Patrick Collison called tokens “the central currency for companies building with AI.” OpenRouter CEO Alex Atallah said the stack stays multi-model, and that Stripe’s neutrality is why they sold. Named customers in the coverage: NVIDIA, Zoom, Lovable.
The close is expected in the coming weeks, subject to customary conditions. OpenRouter’s last disclosed round is the May raise: $113 million at about $1.3 billion. Stripe declined to comment on price for this deal.
What I would actually do this week: do not migrate. No stack rewrite. If you already route through OpenRouter, Atallah’s line is the one that matters. Multi-model stays. Neutrality is the reason they sold. Watch whether Token Billing and the gateway get productized as one invoice, and whether any provider gets a quieter default. Do not rip out a working router because a payments company bought it. Do log that your routing vendor is about to sit inside Stripe. The risk for a long agent loop is not that OpenRouter disappears. It is that “neutral multi-model” slowly becomes “neutral, plus a Stripe-shaped default.” Procurement watch item, not a rewrite.
Same day, August 19, OpenAI pushed GPT-5.6 August snapshots into ChatGPT. Source of record for the in-week event: the GPT-5.6 August update on OpenAI’s deployment-safety hub. This replaced GPT-5.5 Instant. It is a consumer refresh, not a new flagship generation.
| Surface | What you get now | What did not move |
|---|---|---|
| ChatGPT Free and Go | GPT-5.6 Luna as the default | Not a new model family |
| ChatGPT Plus and Pro | Updated GPT-5.6 Sol, with an effort slider | Still Sol, August snapshot |
| Codex, and ChatGPT Work | July Sol / Luna | They kept the July snapshots |
API pricing for gpt-5.6-sol is the number I would actually change a bill over. Docs: GPT-5.6 Sol on the OpenAI API.
| Meter | Price | What changed |
|---|---|---|
| Input | $4 per 1M | 20% cut vs prior Sol |
| Output | $20 per 1M | 33% cut vs prior Sol |
| Cached input | $0.40 per 1M | The cache is the real lever on a long loop |
| Promo window | At least through November 21, 2026 | Do not assume the cut is permanent past that date |
| Context | 1,050,000 | Long-context Sol |
| Max output | 128,000 | |
| Knowledge cutoff | February 16, 2026 |
Safety, from OpenAI, not from a third-party leaderboard. Same Preparedness as July GPT-5.6: High in Biological/Chemical and Cybersecurity, below High in AI Self-Improvement. First dedicated U18 evals in the system card. On HealthBench Professional (length-adjusted), Sol August scored 54.0 against GPT-5.5 Instant at 38.4. OpenAI says factual-error rates on high-stakes prompts are down about 60% versus 5.5 Instant. That is their own eval, not a production-prevalence number. I will not pretend it is.
Same-week company context, not a model story: on August 17, CNBC reported Greg Brockman calling the recent exits (Denise Dresser, Brad Lightcap, and earlier Fidji Simo) not atypical, with Dali Rajic as the new CRO. July run-rate was up 20% month over month, business customers up 32%. Confidential IPO filing in June. CNBC cites an $852 billion valuation. Useful as “they can cut Sol and still be in a growth posture.” Useless as a reason to pick Luna over Sol on a coding loop.
I am not restating the Kimi K3 / Fable 5 / GPT-5.6 Sol bake-off here. August Sol is cheaper than the Sol I already priced. That is the delta.
August 21: DeepSeek shipped an experimental multimodal checkpoint, deepseek-v4-flash-vision-exp. Source: DeepSeek’s August 21 API note.
Official claim, not my bench: text, agent, and knowledge parity with V4-Flash, and a “major leap” on multimodal-agent benches to “close to Opus-4.8.” I am leaving the leap in quotes. I have not rerun it.
Same day: DeepSeek Harness 0.1.1, and a free Files API with file_id reuse. Mixed text plus image via base64, URL, or the Files API. Surfaces: Chat Completions, Messages, Responses. Images billed at V4-Flash rates, capped at 384 tokens each. Vision is experimental. It is not in the stable catalog.
| Item | Fact |
|---|---|
| Model id | deepseek-v4-flash-vision-exp |
| Status | Experimental. Not stable catalog |
| Text / agent / knowledge | Officially parity with V4-Flash |
| Multimodal-agent claim | “Close to Opus-4.8” on their multimodal-agent benches |
| Image billing | V4-Flash rates, 384 tokens cap per image |
| Files | Free Files API, file_id reuse |
| Harness | 0.1.1, same day |
When I would reach for it: a V4-Flash agent loop that suddenly has screenshots or UI dumps, and I do not want to jump the bill to a frontier multimodal SKU. When I would not: anything a client will still be running unmodified in October. Experimental means the id can move. Pair it with the V4 Flash price-war note if you need the text-only cost picture. This post is only the vision add-on.
Cursor’s changelog listed Origin on August 17. TechCrunch covered it on August 18, on a day GitHub was having a very public week: Cursor changelog, TechCrunch on Origin.
Origin is early beta on all paid plans. Enterprise admins can opt out. Native repos, PRs, code browsing, two-way GitHub sync. Official line, in the product’s own words: “Pushes keep going to GitHub, which stays the source of truth for anything started there.” Repo URLs look like cursor.com/codebase/<name>. Launch integrations: Vercel, Depot, Buildkite. Agent-native features ship soon.
The launch overlapped a long GitHub global degradation. TechCrunch: more than 6 hours, about a 20% error rate. That overlap is why Origin got read as a hosting play, not just a settings page. Cursor is now officially part of SpaceX, per the same TechCrunch piece. I am not repeating secondary deal terms I did not fetch from a primary.
August 19 changelog, same week: cloud-agent subscriptions, /goal, and subagents on their own VMs. That is the agent-runtime story sitting next to the Git-host story. Do not collapse them.
| Piece | Origin, today | Still GitHub |
|---|---|---|
| Who can use it | Early beta, all paid plans (enterprise can opt out) | Default remote for repos that started there |
| Source of truth | Two-way sync | Officially still source of truth for anything started on GitHub |
| Review surface | Native PRs and code browsing | Pushes keep going to GitHub |
| CI / deploys at launch | Vercel, Depot, Buildkite | Whatever you already wired |
| Agent runtime (Aug 19) | Cloud-agent subscriptions, /goal, subagents on their own VMs |
Not a Git-host feature |
Why a Git host matters for agents: the loop is checkout, edit, test, PR, retry. If the host flakes for six hours, the agent does not look smart. It looks stuck. Origin is a hedge with an explicit “GitHub remains source of truth” contract, not a flag-day migration. I would turn it on for a throwaway paid-plan repo and keep production remotes where the rest of the team already reviews.
See Grok 4.6, frontier agents in Cursor for the model-in-the-loop half. Origin is the repo half.
August 18: Etched raised $700 million at $21 billion, led by Jane Street, after Jane Street tested the hardware and took the first rack. Company post: Etched, From Zero to One. Recap: TechCrunch.
Jane Street, on Etched’s site: they tested the chip, they are pleased with the early results, and they are excited to have their own rack running in their datacenter. That is a buyer with a rack, not a logo on a seed deck.
Etched sells full frontier inference clusters, not single-model ASICs. COO Robert Wachen told TechCrunch the systems pair a prefill chip with cluster-scale memory for decode, and that they run any frontier model. If you have been waiting for “the one model chip,” that is not this company.
| Date | What | Valuation |
|---|---|---|
| December | Prior mark | $5 billion |
| July 23, 2026 | $300 million Series C | $10.3 billion |
| August 18, 2026 | $700 million, Jane Street-led | $21 billion |
Named backers around the company: Kleiner Perkins, Sequoia, a16z, Peter Thiel, Tiger Global, Bain, Neo, Stripes, Primary, Positive Sum, Diffusion, Argo, Blackstone.
What a builder does with a $21 billion inference-cluster round: almost nothing this week, unless you buy clusters. The tell I care about is Jane Street putting a rack in their own datacenter after testing it. Watch cluster pricing and whether “any frontier model” stays true once the first production racks are full. Do not rebuild an agent graph around a chip you cannot buy.
Two August 20 product-and-deployment notes. Neither changes my default model id. Both change where work shows up.
Slack Code. Slack launched coding-agent channels: Slack’s own post, with a product recap from The Verge. You tag a coding agent. It spins up a project code channel with diffs, a plan, and a live HTML preview. The channel auto-archives as an audit log. Launch partners: Claude (Anthropic), Devin (Cognition), GitHub Copilot, Vercel. Slack’s line on OpenAI: ChatGPT “available soon.” I am using Slack’s wording, not a secondary partner list.
Available today on any Slack plan. Partner-agent access is separate. Slack claims more than 70% of its internal code channels go idea-to-merged-PR in one day. That is a company stat, not an audited one. I will not cite it as a productivity law. If your team already lives in Slack, this is how a non-IDE stakeholder gets into the loop without a Cursor seat. If they do not, it is another inbox.
Nevada robotaxis, short. I write an AI-coding blog. I am not pretending this is a Cursor changelog. On August 20 the Nevada Transportation Authority unanimously approved commercial robotaxi permits in Clark County (Las Vegas). Caps over 12 months: Tesla 5,000, Waymo 1,000, Uber 1,000 via Motional and Zoox. Combined ceiling: 8,000. Zoox already has a 100-vehicle network permit. Tesla Cybercab chief engineer Eric Early said 5,000 is a ceiling, they would be extremely happy with about 2,500 in a year, “not because of the technology.” The Livery Operators Association opposed. Source: TechCrunch.
File it as: autonomy is being permitted in volume in one US county, with a hard cap and an incumbents’ objection. Then go back to your eval harness.
Gemini 3.7 Flash went GA on August 13, not this week. I am only parking the live price and the two benches Google published, so nobody “discovers” it in September and thinks it is new. Google’s Gemini 3.7 Flash post: intro price $0.75 / $3.75 per 1M input/output through December 31, 2026, then it doubles on January 1, 2027 to $1.50 / $7.50. FrontierCode 1.1: 43.6% vs 34.4%. DeepSWE v1.1: 65.3% vs 49.0%. It powers Gemini Spark in 160+ countries. If you have not priced a Flash-class Google SKU since early August, this is still the card to use. It is not a story from August 16 to 22.
I would not throw out the shortlist from GLM-5.3, V4 Pro 0813, V4 Flash, Kimi K3, or Grok 4.6. I would change pipes, prices, and one experimental multimodal id.
| If you are here | Change this week | Do not change |
|---|---|---|
| Already on OpenRouter | Log the Stripe deal. Watch Token Billing plus routing as one vendor. Keep the multi-model fallback you have | Do not migrate off OpenRouter because of an unclosed acquisition |
| Paying prior Sol on the API | Move the cost model to $4 / $20, cached $0.40, promo at least through November 21, 2026 | Do not assume ChatGPT Plus Sol is the same meter as gpt-5.6-sol, or that Codex moved |
| ChatGPT-only users | Expect Luna on Free/Go, August Sol on Plus/Pro | Do not tell a Work or Codex user that their snapshot changed. It did not |
| V4-Flash agent that now sees images | Trial deepseek-v4-flash-vision-exp with the 384-token image cap |
Do not put an experimental id in a client’s stable catalog |
| Cursor on a paid plan, GitHub pain this month | Turn Origin on for a non-production repo. Keep GitHub as source of truth | Do not sell a GitHub-exit |
| Buying inference clusters | Ask Etched about a rack, Jane Street-style | Do not rewrite prompts around a chip you cannot order |
| Team lives in Slack | Pilot Slack Code with Claude, Devin, Copilot, or Vercel. Budget partner-agent access separately | Do not treat the 70% internal Slack stat as your team’s cycle time |
| Flash-class Google SKU still unpriced | Use the August 13 Gemini 3.7 Flash intro card through December 31 | Do not log it as a this-week launch |
Two rules I am using on retainers this month. Separate surface from model: ChatGPT Luna, gpt-5.6-sol, Codex-on-July, Origin, Slack Code, and OpenRouter are different products. Do not mix them before you change a default. Separate closed price from reported price: Sol’s $4 / $20 is in the API docs. Stripe’s deal value is not. Etched’s $21 billion is a priced round. If a number has no primary, it does not go in the cost model.
The week of August 16 to 22 was a pipes week. Stripe is buying the router. Cursor is hosting the repo. Slack is hosting the review channel. OpenAI is snapshotting ChatGPT onto GPT-5.6 August and putting a real cut on Sol. DeepSeek is letting V4-Flash see. Etched is selling clusters at a $21 billion mark. Nevada is permitting robotaxis. None of that is a reason to throw out last week’s shortlist. It is a reason to check who invoices you, which snapshot you are actually on, and whether an experimental vision id belongs in a loop that has to survive October.
If you need a next step that is not another tab of vendor benches: try one real multi-file task with tools, constraints, and a deadline. Leaderboards help you shortlist. Delivery decides.
If you want help picking a model stack that still ships under real usage and cost constraints, start on the contact page.
Z.ai released GLM-5.3 on August 14, 2026. Same 743B mixture-of-experts base as GLM-5.2. Every reported gain is post-training, not a new architecture. It is live now on the GLM Coding Plan and ZCode. The API and downloadable weights are staged behind a safety review, with public weights expected around August 28.
I am writing this a few days later with the same builder lens I used for DeepSeek V4 Pro 0813, V4 Flash, Kimi K3, and Grok 4.6: not who won the internet, but what I would put on a long agent loop and how the bill looks when that loop runs all week. The access and procurement half of the Chinese-model story is still in Kimi K3, a possible US ban, and why some builders pick Codex.
Z.ai’s own framing is useful. It calls GLM-5.3 the most capable open-weights model for coding, then still puts Claude Fable 5 and GPT-5.6 Sol ahead on several of the hardest rows. That is open-weight coding and agent competition, not a closed-flagship takeover.
The other half of the story is the calendar. The same week GLM-5.3 shipped, xAI, Google, DeepSeek, Alibaba, Meta, and NVIDIA all moved. The AI race is not one model card. It is cadence plus price.
GLM-5.3 reuses the GLM-5.2 base and scales post-training across longer-horizon coding, terminal, and agent environments. Decrypt and Unite.AI both stress that point: the architecture did not change. The recipe did.
| Spec | GLM-5.3 |
|---|---|
| Total params | 743B MoE |
| Base | Same as GLM-5.2 |
| What changed | Post-training only |
| Focus | Coding, agents, long-horizon tool use |
| Access today | GLM Coding Plan and ZCode |
| API | Coming after safety review |
| Weights | Expected around August 28 |
Setup on the Coding Plan is a single command, npx @z_ai/coding-helper, which wires the subscription into Claude Code, OpenCode, ZCode, and a long list of other agent tools. That is the practical path today. There is no GLM-5.3 row on Z.ai’s per-token API table yet.
Mid-August 2026 compressed the release cadence into a few days. Patrick McGuinness’s week-in-review counted five frontier-class systems landing in the top of the board in one week. GLM-5.3 was one of them.
The same window also moved Qwen3.8-2.4T weights, Meta’s Muse Glimmer 30B, NVIDIA Nemotron 3.5 Lightning, ByteDance Seed2.1, and DeepSeek Harness. Western labs are competing on closed cadence and intro discounts. Chinese labs are competing on open weights and per-token economics. Builders get both at once, which is why this week felt exciting instead of noisy.
The scorecard below is from Z.ai’s launch post, max effort. These are vendor rows. Fable 5 figures in that table often include fallback. Do not mix them with Artificial Analysis or Vals without saying so.
| Benchmark | GLM-5.3 | Closest closed / open | Notes |
|---|---|---|---|
| Terminal Bench 3.0 | 28.3 | Sol 34.6; Fable 5 33.7 | Open SOTA. GLM-5.2 was 4.6 |
| Agents’ Last Exam (ALE-CLI) | 28.5 | Sol 28.6 | Open SOTA, a 0.1 gap to Sol |
| AutomationBench v1.0.6 | 48.2 | Fable 5 46.2; Sol 45.8 | Ahead of both closed flagships |
| CyberGym | 84.5 | Fable 5 83.8; Sol 83.6 | Ahead of the closed set |
| Terminal Bench 2.1 | 88.2 | Sol 88.8; K3 88.3; Fable 5 88.0 | Clustered, not a blowout |
| Z.ai Code Bench High | 31.4% | Opus 4.8 29.5% | ~50k output tokens vs ~120k |
The High-effort Code Bench row is the efficiency story I care about for client loops. GLM-5.3 scores a bit above Opus 4.8 while burning far fewer output tokens. At Max effort it reaches 34.5% and still trails Fable 5 at 39.5%. Token economy vs Claude, not a Fable knockout.
| Benchmark | GLM-5.3 | Fable 5 | GPT-5.6 Sol | Other |
|---|---|---|---|---|
| DeepSWE v1.1 | 66.9 | 69.7 | 72.7 | K3 67.5; V4 Pro 0813 62.7 |
| Z.ai Code Bench Max | 34.5 | 39.5 | n/a | vs GLM-5.2 at 23.4% |
| FrontierSWE | 78.1 | 88.2 | n/a | Opus 4.8 66.5 |
| ProgramBench Almost Solved | 19.0 | 33.0 | 23.0 | K3 17.5 |
| SWE-Marathon v1.1 | 42.5 | 33.1 | 42.5 | K3 48.1; Opus 4.8 48.8 |
| HLE with tools | 62.5 | 63.9 | 64.5 | K3 59.8 |
| ExploitBench | 54.4 | 78.0 | 76.5 | Mythos 5 / Fable-class lead |
| ExploitGym 2h / 6h | 105 / 130 | 181 / 247 | 216 / 293 | GLM-5.2 was 29 / 39 |
Reading that as a builder: GLM-5.3 looks strongest as a cheap open coding-and-agent default. It jumped hard on the longest-horizon public boards versus GLM-5.2. Closed flagships still own the hardest single-shot coding, Terminal Bench 3.0, and offensive-security depth. Kimi K3 still nips it on DeepSWE. DeepSeek V4 Pro 0813 is behind on several of these same rows and cheaper on the API.
The CyberGym lead versus the ExploitGym gap is the clean split. Identification and validation scaled. Exploitation still lags Fable and Sol by a wide margin.
Z.ai says cybersecurity skill grew faster than it planned as post-training scaled. Unite.AI’s recap uses that as the headline: a capability that outgrew its training.
On the published boards, that shows up as a lead on CyberGym (white-box identification and validation) and a still-large gap on ExploitBench and ExploitGym (deeper exploitation under time budgets). The company also says the model flagged 2,436 vulnerabilities across 269 open-source projects, 1,097 of them medium-to-high severity. That is a vendor claim, not an independent audit.
It is also why the weights are late. GLM-5.2 went public fast. GLM-5.3 waits on safety evaluation and hardening. For delivery work that is the useful fact: stronger defensive scanning in an agent loop is interesting, and I am not treating a cyber leaderboard as a reason to point this model at anyone else’s systems.
GLM-5.3 itself has no published per-token API row. Do not copy GLM-5.2’s sticker onto 5.3 and call it official.
What you can budget today:
| Path | Price | What it is |
|---|---|---|
| GLM Coding Plan Lite / Pro / Max | $18 / $80 / $168 per month | Subscription credits, not API tokens. Promo display is often lower |
| GLM-5.2 API (family anchor) | $1.40 in / $4.40 out per 1M | Live rate card. Not confirmed for 5.3 |
| GPT-5.6 Luna | $0.20 / $1.20 | After the July 30 cut |
| GPT-5.6 Sol | $5 / $30 | Flagship unchanged |
| Claude Fable 5 | $10 / $50 | Premium closed tier |
| Claude Opus 5 | $5 / $25 | Pitched as half of Fable |
| Grok 4.6 | $2 / $6 | Held flat from 4.5 |
| Gemini 3.7 Flash intro | $0.75 / $3.75 | Through December 31, 2026 |
Verify Coding Plan numbers on Z.ai before you subscribe. The $18 / $80 / $168 list is the monthly anchor. Displayed promo prices have been lower.
The reason this table exists is the Chinese undercut, not a sudden burst of generosity from US labs.
On July 30, OpenAI cut GPT-5.6 Luna by 80% to $0.20 / $1.20 and Terra by 20% to $2 / $12. CNBC and Axios both framed it as cost pressure from customers and Chinese open-weight competition.
TechRepublic and the AFR write-up of the Financial Times story (August 14, the same day as GLM-5.3) name DeepSeek, Moonshot’s Kimi, and Zhipu’s GLM as the models forcing the issue. Chinese open-weight rates sit 60-90% below leading Anthropic and OpenAI prices on a per-token basis. Some of that coverage puts a comparable job at roughly 9× cheaper on GLM than on Claude. DoorDash, Airbnb, and Coinbase have confirmed using Chinese models for at least some workloads.
Anthropic’s answer is Claude Opus 5 at $5 / $25, pitched as frontier intelligence at half of Fable. Google’s answer this week is Gemini 3.7 Flash at half the original 3.6 Flash rate through year end. xAI’s answer is more Grok 4.6 capability at an unchanged $2 / $6. DeepSeek went the other way on August 16 and raised effective rates with peak/off-peak billing. That last move is in the V4 Pro 0813 post.
Builder takeaway: token price is becoming a commodity floor. Differentiation shifts to harness quality, latency, compliance, and the slice of work where a closed flagship still earns its markup. GLM-5.3 is another Chinese lab putting near-frontier coding on that floor. US labs are cutting mid-tier prices because the gap on everyday agent work got small enough to steal volume.
When I would reach for GLM-5.3
When I would still pick closed flagships, Grok 4.6, or DeepSeek Flash
GLM-5.3 is a post-training jump that puts open coding within a few points of Claude Fable 5 and GPT-5.6 Sol on several agent boards, at Chinese-lab economics, in a week when Google, xAI, DeepSeek, Qwen, and Meta all shipped. It leads some automation and defensive-security rows. It still trails on the hardest coding and exploitation benches. The weights are not out yet, and the API sticker is not published yet.
That is enough to shortlist. It is not enough to lock a stack. Try the same test I use for every release: one real multi-file task with tools, constraints, and a deadline. Leaderboards help you shortlist. Delivery decides.
If you want help picking a model stack that still ships under real usage and cost constraints, start on the contact page.
DeepSeek made DeepSeek-V4-Pro-0813 the official flagship on August 12-13, 2026. The tell was a version string on the pricing page and a changelog entry the next day. No company blog. No press post. Same API id: deepseek-v4-pro.
I am writing this the next day with the same builder lens I used for V4 Flash, Kimi K3, and Grok 4.6: not who won the internet, but what I would put on a long agent loop and how the bill looks when that loop runs all week. The access and procurement half of the Chinese-model story is still in Kimi K3, a possible US ban, and why some builders pick Codex.
This is the Pro follow-through the Flash post was waiting on. Flash 0731 already owns the volume-and-price story. 0813 is the 1.6T flagship leaving preview, plus a rate card that changes at 16:00 UTC on August 16.
DeepSeek V4 first landed as a preview pair on April 24, 2026. Flash graduated on July 31. Pro stayed on the April checkpoint until this week. 0813 is a post-training update on the same MoE, not a new architecture.
| Spec | V4 Pro 0813 | V4 Flash 0731 |
|---|---|---|
| Total params | 1.6T | 284B |
| Active per token | 49B | 13B |
| Context | 1M tokens | 1M tokens |
| Max output | 384K | 384K |
| License | MIT | MIT |
| API id | deepseek-v4-pro |
deepseek-v4-flash |
| Concurrency | 500 | 2,500 |
| Modalities | Text only | Text only |
Thinking modes are now low / high / max on both Pro and Flash. Thinking is on by default at high. Thinking tokens bill at output rates even when they never show up in the final answer, which matters more on long agent traces than the sticker does.
The API still speaks OpenAI ChatCompletions, Anthropic Messages, and the Responses API, with a Codex-oriented setup. Tool calls and JSON output stay on. There is no vision.
Weights for 0813 live on Hugging Face, with a DSpark speculative decoding module attached. The older preview-era Pro card still exists. Do not assume a local checkout of the April files is the same checkpoint the API now serves.
Launch charts are one input. Here is what showed up in the first days of actual use, with numbers attached where people published them.
The drop was quiet on purpose. Decrypt and TechTimes both noted there was no announcement post. The vendor table circulated via DeepSeek’s WeChat group, then into Reddit and Hacker News. Anyone already calling deepseek-v4-pro was already on 0813. No key rotation. No new endpoint.
Capability vs the closed frontier is the split reaction. SCMP reported some developers underwhelmed on overall IQ and unhappy about the coming price hike, while cybersecurity researchers were more impressed. Vals AI, in that same coverage and on its own index, flagged sandboxed terminal work and Excel financial models as the weak spots.
OpenRouter traffic is the first operational snapshot. On DeepSeek’s own provider, OpenRouter showed about 53 tok/s, 1.67s latency, a ~93% cache-hit rate, and about a 2% tool-call error rate. Cache hits are why the effective input price sits far below the $0.435 list. Tool-call errors are why I would not treat “it speaks the Responses API” as a free pass for strict JSON schemas.
One first-day coding trial already lives on this site. In the Grok 4.6 post, a first-day roundup ran the same new feature through Codex CLI on OpenRouter: DeepSeek V4 Pro 0813 took 12 minutes 2 seconds, cost $0.12, and shipped a bug. Grok 4.6 took 3 minutes 18 seconds, cost $1.41, and shipped clean. That is roughly 3.6× faster and about 12× more expensive, with a working result against a broken one. One trial is a signal, not a bake-off. It matches the rest of the reception: cheap and usable, not the model I would pick when wall time and a clean first pass matter more than the token bill.
The August 13 changelog is the vendor scorecard. These rows are DeepSeek Harness, max effort. Flash 0731 numbers are from the July 31 note. Pro preview DeepSWE and Cybergym come from the table TechTimes reproduced from DeepSeek.
| Benchmark | V4 Pro preview | V4 Flash 0731 | V4 Pro 0813 |
|---|---|---|---|
| Terminal Bench 2.1 | 72.1 | 82.7 | 87.9 |
| DeepSWE | 12.8 | 54.4 | 62.7 |
| Cybergym | 52.7 | 76.7 | 83.3 |
| NL2Repo | n/a | 54.2 | 61.5 |
| Toolathlon-Verified | n/a | 70.3 | 74.1 |
| Agents’ Last Exam | n/a | 25.2 | 25.7 |
| AutomationBench (Public) | 12.8 | 25.1 | 31.8 |
| HLE (wo / w tools) | n/a | n/a | 42.7 / 60.0 |
| DSBench-FullStack | 41.8 | 68.7 | 71.1 |
| DSBench-Hard | 31.1 | 59.6 | 67.2 |
On DeepSeek’s board, 0813 retakes the agent lead Flash 0731 had over the April Pro preview. Decrypt’s read of the same vendor comparison against Claude Fable 5: Fable ahead by about 5.3% on average across overlapping agent rows, or 2.8% if you drop HLE without tools. Pro wins two of those rows. Terminal Bench 2.1 is a 0.1-point gap (87.9 vs 88.0). That is the “Fable is only 5% better” headline. It is DeepSeek’s table, not an independent bake-off.
Do not mix these with the vendor rows. Artificial Analysis and Vals ran their own harnesses. Recaps such as Office Chai walk the AA scorecard.
| Model | AA Intelligence Index (max) |
|---|---|
| Claude Opus 5 | 63 |
| Claude Fable 5 | 62 |
| GPT-5.6 Sol / Grok 4.6 | 61 |
| Kimi K3 | 60 |
| Muse Spark 1.2 | 57 |
| DeepSeek V4 Pro 0813 | 53 |
| GLM-5.2 | 53 |
| DeepSeek V4 Flash 0731 | ~52 |
| GPT-5.6 Luna | 52 |
That is an 8 to 10 point gap to the closed flagships I actually compare against for client work. OpenRouter also lists AA Coding Index around 68.8 and Agentic Index around 49.6 for 0813.
Selected AA rows from that same recap:
Vals AI is harsher on the jobs that look like delivery work. V4 Pro 0813 scores 66.25% on the Vals Index, rank #12 of 47, up from 55.62% on the preview. Terminal-Bench 2.1 comes in at 54.68% (#33 of 52). EMB, the Excel modeling board, is 52.80%. Three different Terminal-Bench 2.1 numbers (87.9 vendor, 79 AA, 54.68 Vals) is the whole story: harness plus policy plus effort, not a single model IQ.
Composite IQ. 0813 is not a takeover. On AA it sits with GLM-5.2 in the low 50s. Fable 5, Sol, Grok 4.6, and Opus 5 still live in the low 60s. Kimi K3 is closer to that closed band than Pro is.
Price per point. This is still DeepSeek’s actual product. AA puts 0813 on the Pareto frontier with Flash. Office Chai’s read: climbing from DeepSeek’s 53 to Opus 5’s 63 costs about 39× more per task at current list. Decrypt’s blended-rate framing is similar: Fable at about $30 versus Pro at about $0.65, roughly 46×. Those ratios shrink after August 16. They do not disappear.
Coding and agents. DeepSeek’s table says near-Fable on Terminal-Bench 2.1 and ahead of Opus 4.8 on several agent rows. Independent AA and Vals say terminal loops and Excel still lag. The eesel Codex trial says Grok 4.6 was faster and shipped clean on one real feature. I would not pick 0813 over Grok inside Cursor when I already have 4.6 in the picker. I would pick 0813 over Fable when the job is a long, cache-heavy loop and the client can accept the route.
Context and openness. 1M context matches Flash, Kimi K3, and Muse Spark, and beats Grok 4.6’s 500K. MIT weights are the self-host path the closed flagships do not offer. Confirm you are pulling the 0813 files, not the April preview card.
Gaps that still matter. Text only. No vision. Concurrency 500 versus Flash at 2,500. Thinking tokens bill as output. Procurement still matters: cheap Chinese open models are exactly why US teams adopted them, and exactly why some stacks cannot use them. See the Kimi ban and coding plans post.
Official API rates through 16:00 UTC on August 16 (cache-miss input / cache-hit input / output, per million tokens). Verify on the DeepSeek pricing page before you budget:
| Model | Input (miss) | Input (hit) | Output |
|---|---|---|---|
| DeepSeek V4 Flash | $0.14 | $0.0028 | $0.28 |
| DeepSeek V4 Pro | $0.435 | $0.003625 | $0.87 |
| Grok 4.6 | $2.00 | $0.50 | $6.00 |
| GPT-5.6 Sol | $5.00 | n/a | $30.00 |
| Claude Fable 5 | $10.00 | n/a | $50.00 |
Worked examples at current Pro rates (approximate, uncached unless noted):
Peak / off-peak billing starts at 16:00 UTC on August 16. Off-peak is half of peak. Peak hours are 01:00-04:00 and 06:00-10:00 UTC.
| Model | Off-peak (miss / hit / out) | Peak (miss / hit / out) |
|---|---|---|
| V4 Flash | $0.22 / $0.007 / $0.66 | $0.44 / $0.014 / $1.32 |
| V4 Pro | $0.66 / $0.022 / $1.98 | $1.32 / $0.044 / $3.96 |
After the reset, that same 100K / 4K document job is about $0.074 off-peak and about $0.148 at peak. Still cheap next to Fable. Not the $0.047 you can quote this week.
When I would reach for DeepSeek V4 Pro 0813
When I would still pick Flash
When I would still pick Fable 5, GPT-5.6 Sol, or Grok 4.6
V4 Pro 0813 is the official flagship, not a new architecture. On DeepSeek’s board it retakes the agent lead Flash 0731 had over the April preview, and sits within a few points of Fable on several vendor agent rows. On Artificial Analysis it is still about 10 points off Opus 5, Fable 5, Sol, and Grok 4.6, at a cost per task that is still in a different league until August 16. Independent terminal and Excel boards are less kind than the changelog. The quiet launch was the version string. The loud part is the rate card.
Leaderboards help you shortlist. Delivery decides. Try the same test I use for every release: one real multi-file task with tools, constraints, and a deadline.
If you want help picking a model stack that still ships under real usage and cost constraints, start on the contact page.
xAI released Grok 4.6 on August 12, 2026. Cursor published a matching joint launch post the same day. I first wrote this the next day with the same builder lens I used for Muse Spark 1.2, Kimi K3, and DeepSeek V4 Flash: not who won the internet, but what I would put on a long agent loop for product and agency work. This update folds in what users actually reported in the first 24 hours.
The important framing is that this is a long-running-agent update on the Grok 4.5 line, not a raw scale jump. The official posts never publish a parameter count, so I am not inventing one. What they do claim is that 4.6 stays with research, codebase work, and “idea to working first version” jobs across many steps, with stronger visual first passes than 4.5.
This post is also the delivery test. I planned and wrote it with Grok 4.6 inside Cursor, the same loop I used to ship the blog with Grok 4.5.
Grok 4.6 is live in Cursor, Grok Build, the SpaceXAI API, and partners including OpenRouter, Vercel, and Cloudflare. For the first week, xAI and Cursor are offering 2x included usage inside Cursor and Grok Build.
Documented specs from the xAI models docs and reasoning docs:
grok-4.6Training, as described in the launch posts: a longer supplemental run than 4.5, with curated model-generated data for reasoning and technical concepts, high-quality engineering data, and an improved optimizer. Grok 4.5 then regenerated SFT trajectories across reasoning efforts, agent harnesses, and domains such as STEM, software engineering, and knowledge work, with model-based filters on bad traces. RL covered general coding, knowledge work, and domain environments for kernel optimization, web development, and CAD.
That last point is the practical contrast with Muse Spark 1.2. Muse Code launched as a macOS/Linux terminal beta with no Cursor plug-in. Grok 4.6 is already in the IDE where I ship.
The UX story is less a new agent product and more how the model behaves on long jobs.
Long-horizon stickiness. xAI positions 4.6 to research an unfamiliar domain, structure an application, implement the core interactions, and keep refining through several rounds of feedback without dropping the thread.
Self-testing on longer trajectories. The launch materials say the model started checking its own work before moving on more often than 4.5 did. That is the behavior I care about in Cursor agent loops: fewer silent half-finished steps.
Stronger visual and interactive first passes. Given a concrete product idea, 4.6 is meant to establish structure and visual language in one pass, then iterate. That matches how I already use this stack for portfolio and client UI work.
Where I can actually test it. Grok Build remains the terminal agent path (curl -fsSL https://x.ai/cli/install.sh | bash). Cursor is the daily path. Unlike Muse Code’s Windows gap, I can run 4.6 on this machine inside the same editor that already holds this repo. Cursor’s own docs still split the stack: Composer for everyday speed and cost, Grok 4.6 for harder, longer sessions. On Pro and higher, Fast is the default speed tier. On Cursor Start, 4.6 is locked to medium effort in non-fast mode.
Launch charts are one input. Here is what showed up in the first day of actual use, with numbers attached where people published them.
Cursor landed a few hours after the API. On the morning of August 12, a Cursor forum thread asked when 4.6 would appear in the Agent / Chat picker. The user still only saw 4.5, and said 4.5 was usable but not good enough day to day. Cursor staff confirmed it was live later that afternoon in the Grok 4.6 is now Live announcement, with 2x included usage for the first week and Composer still positioned as the everyday model.
Speed is the loudest first-day report. A first-day roundup collected a Codex CLI head-to-head on the same new feature, both via OpenRouter: DeepSeek V4 Pro 0813 ran 12 minutes 2 seconds, cost $0.12, and shipped a bug. Grok 4.6 ran 3 minutes 18 seconds, cost $1.41, and shipped clean. That is roughly 3.6× faster and about 12× more expensive, with a working result against a broken one. One trial is a signal, not a bake-off. The same roundup quotes an engineer who left Claude after 4.5 and especially 4.6, calling Grok 3×+ faster with no obvious drop in engineering quality, and another whose old split was Sol for planning and Grok for building. After first tests, they were ready to use 4.6 for both.
Cache price is the first-day asterisk. Headline $2 / $6 did not move from 4.5. Cached input did: $0.30 to $0.50 per million tokens, and $0.60 to $1.00 on long-context cache. Heavy coding sessions are mostly cache reads. Users caught that within hours. OpenRouter’s early traffic snapshot in the same roundup showed about 90% cache hits, ~94 tokens/s, ~0.62s latency, and a 4% structured-output error rate on the standard endpoint versus 0% on the ZDR endpoint. If you pin JSON schemas for tools, test both.
The honest prior after one day. Independent hours on 4.6 are still thin. One first-day take, framed as speculation rather than a test, put real-world 4.6 around Opus 4.8 and clearly below Opus 5. That matches the benches: close on CursorBench and knowledge work, still behind Sol and Fable on DeepSWE and Terminal-Bench v3.0. Artificial Analysis also published an AA-Omniscience non-hallucination rate around 65.7%. For a coding agent, a wrong answer often dies in a test. For a customer-facing agent, it gets sent. I am not treating one day of forum and OpenRouter traffic as a verdict. I am treating it as the first filter: faster than Claude for several engineers, more expensive than Flash, watch the cache line, keep Composer for small edits.
xAI published a head-to-head against Grok 4.5 High, GPT-5.6 Sol Max, and Fable 5 Max. Competitor figures come from published system cards or leaderboards, not from xAI running every rival in one shared harness. Recaps such as Office Chai and DEV walk the same scorecard.
| Eval | Grok 4.6 High | Grok 4.5 High | GPT-5.6 Sol Max | Fable 5 Max |
|---|---|---|---|---|
| AA Intelligence Index | 61 | 56 | 61 | 62 |
| GDPVal-AA v2 | 1753 | 1526 | 1728 | 1741 |
| CursorBench v3.2 | 69.9% | 66.7% | 67.2% | 70.5% |
| DeepSWE v1.1 | 65.9% | 54% | 73% | 70% |
| FrontierCode v1.1 (Extended) | 61.3% | 56.6% | 60.6% | 63.6% |
| APEX-Agents | 57.5% | 47.1% | 56.7% | 59.2% |
| Terminal-Bench v3.0 | 26% | 15.7% | 34.6% | 34.1% |
| APEX-SWE | 56.4% | 53.6% | n/a | 58.8% |
| AA-Briefcase | 1577 | 1313 | 1502 | 1574 |
| Harvey LAB (Vals) | 15.8% | 12.9% | 2.5% | 11.3% |
On that same table, Grok 4.6 High beats Grok 4.5 High on every published row.
| Change | 4.5 High | 4.6 High | Delta |
|---|---|---|---|
| AA Intelligence Index | 56 | 61 | +5 |
| GDPVal-AA v2 | 1526 | 1753 | +227 Elo |
| DeepSWE v1.1 | 54% | 65.9% | +11.9 points |
| Terminal-Bench v3.0 | 15.7% | 26% | +10.3 points |
| CursorBench v3.2 | 66.7% | 69.9% | +3.2 points |
Terminal-Bench v3.0 still leaves 4.6 last among the four. CursorBench lands almost on Fable (70.5%). Against the closed flagships the pattern is mixed: tie with Sol on the composite, leads on GDPVal-AA, AA-Briefcase, and Harvey LAB, close on CursorBench and FrontierCode, still behind on DeepSWE and Terminal-Bench v3.0.
On coding specifically, the practical split looks like this:
Builder reading: knowledge-work and IDE coding loops look closer to the flagships. Raw terminal and repo SWE still favors Sol and Fable.
List rates from the xAI models docs. Prompts at or above 200k tokens bill at 2x for the whole request. A fast variant is twice the list price.
| Model | Input / 1M | Cached input / 1M | Output / 1M |
|---|---|---|---|
| Grok 4.6 (< 200k prompt) | $2.00 | $0.50 | $6.00 |
| Grok 4.6 (≥ 200k prompt) | $4.00 | $1.00 | $12.00 |
| GPT-5.6 Sol | $5.00 | n/a | $30.00 |
| Claude Fable 5 | $10.00 | n/a | $50.00 |
| Muse Spark Standard | $1.25 | $0.15 | $4.25 |
| DeepSeek V4 Flash | $0.14 | $0.0028 | $0.28 |
Honest status: Grok 4.6 is in Cursor today. That is the difference that matters for me.
I planned this article and wrote the MDX with Grok 4.6 in Cursor: research the launch materials, lock the outline to this site’s blog voice, build the benchmark tables, and keep Sources honest. Same delivery shape as Building this blog with Cursor and Grok 4.5: multi-file constraints, outcome-led copy, no invented metrics.
xAI and Cursor are offering 2x included usage in Cursor and Grok Build for the first week. That is the window to point 4.6 at a real multi-file task with tools, constraints, and a deadline. I am not inventing a usage screenshot for this session. The 4.5 post already showed what that meter looks like on a similar feature.
When I would reach for Grok 4.6
When I would still pick something else
Grok 4.6 is a real step up from Grok 4.5 on xAI’s agentic board. It now sits in the Fable / Sol composite band at $2 / $6, and it is already inside Cursor with a first-week usage promo. The first 24 hours of user reports line up with that: faster than Claude for several engineers, more expensive than Flash, cache reads cost more than 4.5, Composer still wins small edits. It is not a verified sweep of DeepSWE or Terminal-Bench v3.0.
Leaderboards help you shortlist. Delivery decides. This post is one delivery test: planned and written with Grok 4.6 in Cursor.
If you want help picking a model stack that still ships under real usage and cost constraints, start on the contact page.
Meta released Muse Code (beta) and Muse Spark 1.2 on August 5, 2026. I am writing this two days later with the same builder lens I used for Kimi K3 and DeepSeek V4 Flash: not who won the internet, but what I would put on a long agent loop for product and agency work.
Muse Spark 1.3 shipped September 2, 2026. The builder comparison, including max reasoning and the Cursor gap, is in Muse Spark 1.3 vs the frontier: max reasoning, cheaper loops, still not in Cursor.
The important framing is that this is a model plus harness product. Muse Spark 1.2 was co-trained with Muse Code. Meta’s coding benches mostly compare Muse Code against Claude Code, Codex, Grok Build, and similar agent products. That is closer to how developers ship than a bare model bake-off. It also means you should not treat the launch chart as a clean ranking of raw model IQ.
Muse Spark 1.2 is a coding-focused update to Muse Spark 1.1. Meta says it scaled training compute on coding tasks, widened training environments, and kept general agent strength. Context stays at 1M tokens. Access is through Muse Code, the Meta Model API with expanded global access (1.1 was US-only), and OpenRouter. Treat it as a hosted proprietary model: no downloadable weights in the launch materials.
Muse Code is a terminal coding agent for macOS and Linux, installed with a single curl command. There is no dedicated desktop app and no IDE plug-in at launch. On Windows, that is an immediate workflow gap for me: my daily shipping loop lives in Cursor on this machine, not a Linux terminal agent.
Meta also co-trained the model with the harness using rejection-sampled trajectories, goal conditioning, context compaction, and subagent recipes. That is the same industry move Anthropic and OpenAI made with Claude Code and Codex: the agent shell is part of the product, not an afterthought wrapper.
The UX story is more interesting than another chat box.
Persistent async background agents. Most coding agents spawn a subagent, use it, and discard it. Muse Code keeps specialized background agents alive for the whole session so they accumulate context instead of re-gathering it. They decide when to report back to the main agent. Meta’s bet is less steering and less redundant repo exploration on hard multi-step work.
Append-only local event log. Every model call, tool run, approval, and edit is appended to one log. After a crash, Meta says the runtime can resume exactly where it stopped. That matters for long-horizon jobs more than for a five-minute autocomplete.
Parallel subagents in isolated worktrees. Large tasks can fan out across subagents in separate git worktrees so your working copy stays clean. Meta’s launch demos lean on that for multi-feature work without merge theater.
Bundled skills. /plan turns a task into an approval-gated plan. /grill stress-tests that plan until it holds up. /goal drives toward a stated objective.
Compared with Claude Code, Codex, and Cursor’s agent loops: Muse Code ships a thoughtful runtime for persistence, recovery, and parallel work, on a thinner surface. Terminal beta only. No Windows-native install. No Cursor integration yet. Architecture first, distribution second.
Meta’s methodology and launch coverage (compiled in pieces like Binary Verse AI) put Muse Spark 1.2 with Muse Code near the front of several coding and tool boards. These rows are model plus selected agent product, not one shared harness.
| System | Terminal-Bench 2.1 | DeepSWE 1.1 | Meta Internal | GDPVal-AA v2 | MCP Atlas |
|---|---|---|---|---|---|
| Claude Opus 5 + Claude Code | 86.7% | 65.0% | 79.4% | 1852 | 85.8% |
| Muse Spark 1.2 + Muse Code | 82.9% | 59.3% | 70.6% | 1631 | 90.3% |
| GPT-5.6 Terra + Codex | 81.8% | 64.8% | 65.4% | 1577 | n/a |
| Grok 4.5 + Grok Build | 81.6% | 56.6% | n/a | 1526 | n/a |
| Muse Spark 1.1 | 76.2% verified / Meta claimed 80 | 53.0% | 68.3% | 1371 | 88.1% |
Claude Opus 5 leads most of Meta’s supplied coding and knowledge-work rows. Muse Spark 1.2 is close on Terminal-Bench, improves DeepSWE by about 6 points over 1.1, and leads MCP Atlas at 90.3%. That MCP result is the clearest commercial signal for tool-heavy agent products.
Artificial Analysis scored Muse Spark 1.2 (xhigh) at 54 on the Intelligence Index, up from 51 on 1.1 and 43 on 1.0. That sits effectively tied with Grok 4.5 (54) and near GPT-5.5 (55), still behind Claude Opus 5 (61), Claude Fable 5 (60), GPT-5.6 Sol (59), and Kimi K3 (57).
The gain is concentrated in agentic work. GDPval-AA v2 rose about 260 Elo to 1631 (fifth among models AA has scored, ahead of Claude Opus 4.8). AA’s own Terminal-Bench v2.1 run moved from about 78% to about 80%. Cost per Intelligence Index task lands around $0.40 at Meta’s standard $1.25 / $4.25 pricing, among the cheaper options in that intelligence cluster, though token usage per task rose versus 1.1.
Reading both tables as a builder: Muse is competitive on terminal and repo agent work, strong on MCP-style tool orchestration, and not the composite flagship. Flash and K3 still own different open-price niches. Muse is Meta’s closed coding wedge.
On coding specifically, the practical split looks like this:
Meta is competing on price as hard as capability. Both tiers keep the 1M context window.
| Tier | Input / 1M | Cached input / 1M | Output / 1M | Data use |
|---|---|---|---|---|
| Standard | $1.25 | $0.15 | $4.25 | Meta says not used to improve products |
| Contributor | $0.10 | $0.002 | $0.20 | Prompts and completions used to train / improve Meta products |
Rough worked example from launch coverage: 1M uncached input plus 100K output is about $0.12 on Contributor and about $1.68 on Standard. Cache hits collapse that further.
Honest status: Muse Spark 1.2 is not in Cursor today. My daily IDE stack stays on Composer, Grok, and the other models Cursor already exposes. That is where I already ship this site (Building this blog with Cursor and Grok 4.5).
What I want next is simple: Cursor adds Muse Spark 1.2 (directly or via OpenRouter) so I can run the same multi-file IDE loop I use for client work, without leaving the editor for a macOS/Linux terminal beta. Until that lands, the test path is Meta Model API or OpenRouter for API experiments, and Muse Code CLI only if I am on a supported OS.
If Cursor ships it, the first thing I will do is the same delivery test I use for every release: one real multi-file task with tools, constraints, and a deadline.
When I would reach for Muse Spark 1.2 / Muse Code
When I would still pick something else
Muse Spark 1.2 and Muse Code are a serious Meta coding product: competitive on Meta’s terminal and repo charts, strong on MCP Atlas, thoughtfully built for long-running multi-agent work, and aggressive on API pricing. They are not a verified takeover of Claude Code or Codex. Watch independent Terminal-Bench verification, keep Contributor data terms in mind, and hope Cursor adds the model soon so builders can run the same delivery test inside the editor.
Leaderboards help you shortlist. Delivery decides.
If you want help picking a model stack that still ships under real usage and cost constraints, start on the contact page.
On July 31, 2026 DeepSeek promoted DeepSeek-V4-Flash-0731 from preview to official API public beta. Same 284B MoE with 13B active parameters, same 1M-token context, MIT weights. What changed is the agent post-training and the sticker: $0.14 input / $0.28 output per million tokens on a cache miss.
I am writing this the next day with the same builder lens I used for Kimi K3 and Grok 4.5: not who won the internet, but what I would put on a long agent loop and how the bill looks when that loop runs all week. The access and procurement half of the Chinese-model story is still in Kimi K3, a possible US ban, and why some builders pick Codex.
DeepSeek V4 first landed as a preview pair on April 24, 2026. Flash is the efficiency tier. Pro is the flagship. Both ship open weights under MIT and a default 1M context window with up to 384K output tokens.
| Spec | V4 Flash 0731 | V4 Pro (preview) |
|---|---|---|
| Total params | 284B | 1.6T |
| Active per token | 13B | 49B |
| Context | 1M tokens | 1M tokens |
| Max output | 384K | 384K |
| License | MIT | MIT |
| API id | deepseek-v4-flash |
deepseek-v4-pro |
The 0731 build keeps the same architecture and size as the Flash preview. DeepSeek says it was only re-post-trained. The official Flash API also natively supports the Responses API format and is adapted for Codex. Weights live on Hugging Face.
One migration detail that still bites people: the legacy deepseek-chat and deepseek-reasoner aliases retired on July 24, 2026. Point production traffic at deepseek-v4-flash or deepseek-v4-pro explicitly.
DeepSeek’s own changelog lists a steep jump from Flash preview to 0731 on agent tasks. Several rows also beat the still-preview V4 Pro checkpoint.
| Benchmark | V4 Flash preview | V4 Flash 0731 | V4 Pro preview | Notes |
|---|---|---|---|---|
| Terminal Bench 2.1 | 61.8 | 82.7 | 72.1 | vs Opus 4.8 ~85.0; GLM-5.2 ~81.0 |
| NL2Repo | 39.4 | 54.2 | n/a | |
| Cybergym | 38.7 | 76.7 | n/a | |
| DeepSWE | 7.3 | 54.4 | n/a | |
| Toolathlon verified | 49.7 | 70.3 | n/a | |
| Agents’ Last Exam | 15.8 | 25.2 | n/a | |
| AutomationBench Public | 10.8 | 25.1 | n/a | |
| DSBench-FullStack | n/a | 68.7 | 41.8 | DeepSeek internal set |
| DSBench-Hard | n/a | 59.6 | 31.1 | DeepSeek internal set |
Independent composites tell a similar story at the index level. Reporting around Artificial Analysis puts Flash 0731 around 50 on the Intelligence Index at max reasoning effort, ahead of V4 Pro at 44, while still trailing the closed flagships that sit near the high 50s.
Reading that as a builder: Flash 0731 looks strongest for terminal loops, tool-heavy agents, and high-volume coding automation. Opus-class and Fable-class boards still lead on the hardest single-shot reasoning. The awkward part of this release is that DeepSeek’s own agent numbers put the 284B Flash ahead of the 1.6T Pro preview until the official Pro post-training lands.
Official API rates (cache-miss input / cache-hit input / output, per million tokens). Verify on the DeepSeek pricing page before you budget:
| Model | Input (miss) | Input (hit) | Output |
|---|---|---|---|
| DeepSeek V4 Flash | $0.14 | $0.0028 | $0.28 |
| DeepSeek V4 Pro | $0.435 | $0.003625 | $0.87 |
| GPT-5.6 Luna | $0.20 | n/a | $1.20 |
| GPT-5.6 Sol | $5.00 | n/a | $30.00 |
| Claude Fable 5 | $10.00 | n/a | $50.00 |
| Grok 4.5 | $2.00 | n/a | $6.00 |
On paper, Flash output is about 100× cheaper than Claude Fable 5 and about 4× cheaper than GPT-5.6 Luna after OpenAI’s July 30 cut. Cache hits make the gap wider still: $0.0028 per million cached input tokens is a 98% discount off the miss rate.
Worked examples at Flash rates (approximate, uncached unless noted):
That is the shape that changes product math. A feature that was too expensive to run on every ticket or every PR becomes cheap enough to leave on by default.
The calendar around this release is the story as much as the model card.
On July 30, OpenAI cut GPT-5.6 Luna by 80% to $0.20 / $1.20 and Terra by 20% to $2 / $12. Sol stayed at $5 / $30. OpenAI credits GPT-5.6 Sol with rewriting production GPU kernels and cutting end-to-end serving cost by about 20%. CNBC and Axios both framed the move as cost pressure from customers and Chinese open-weight competition, not charity.
On July 31, DeepSeek answered with official Flash 0731 at $0.14 / $0.28. That undercuts Luna on output within hours. Coverage such as Office Chai and Wccftech treated it as the next volley in an open price war.
DeepSeek also made its 75% V4 Pro discount permanent. The promotion was scheduled to expire May 31; The Next Web reports list rates that would have been $1.74 / $3.48 are now locked at $0.435 / $0.87. Google has been cutting Gemini Flash-class prices through 2026 for the same reason. Anthropic’s flagship Fable tier still lists at a premium; the bet there is that the quality gap on hard reasoning still pays.
Builder takeaway: token price is becoming a commodity floor. Differentiation shifts to harness quality, latency, compliance, and the slice of work where a closed flagship still earns its markup.
That July 31 “follow soon” note landed. deepseek-v4-pro now serves DeepSeek-V4-Pro-0813. I wrote the builder comparison against Fable 5, GPT-5.6 Sol, and Grok 4.6, including the August 16 peak/off-peak rate card, in DeepSeek V4 Pro 0813 vs Fable 5, GPT-5.6 Sol, and Grok 4.6. Flash 0731 remains the volume-and-price default. Reach for official Pro when you need the 49B-active pass and can live with 500 concurrency.
While Chinese open models set the cost floor, xAI is iterating on cadence. On July 28, Elon Musk posted that Grok 4.6 releases around August 7 as a 1.5T model with significantly improved SFT and RL. Grok 4.7 follows a few weeks later as a 2.1T model that Musk says will be better than 4.6 in every way except slightly slower to serve, with even better token efficiency.
That sits on top of Grok 4.5, which went public on July 8 at $2 / $6 and was trained with Cursor for coding and agent work. I already wrote about shipping this site with that stack in Building this blog with Cursor and Grok 4.5.
Western labs are competing on release cadence and closed harnesses. Chinese labs are competing on open weights and per-token economics. Builders get both: a cheaper floor for volume work, and a fast-moving premium tier for the jobs that still need it.
July closed with a price war. August opens with a release stack. Official DeepSeek V4 Pro is due any day. Grok 4.6 targets around August 7, then Grok 4.7 a few weeks after that. OpenAI and Google will not sit still while Chinese open weights keep setting the floor. If you are picking a model stack for a Q3 ship, this is the month to re-benchmark, not the month to lock in last quarter’s defaults.
When I would reach for DeepSeek V4 Flash
When I would still pick closed flagships
V4 Flash 0731 puts near-frontier agent performance at roughly 1/100th the output cost of Claude Fable 5 on paper, and under OpenAI’s freshly cut Luna tier on output price. That is why OpenAI moved Luna 80% the day before. The market is splitting into a cheap open-weight tier and a premium closed tier. August 2026 is going to be juicy: official V4 Pro, Grok 4.6, and Grok 4.7 land in the same window. Shortlist with leaderboards. Decide with one real multi-file task, tools, constraints, and a deadline.
If you want help picking a model stack that still ships under real usage and cost constraints, start on the contact page.
Coding agents ship UI fast. They also ship the same defaults fast: purple meshes, Inter heroes, equal feature cards, and chrome that looks like every other generated landing page.
Open the Impeccable demo landing (new tab) for a live Persuade-mode page built for this post. That HTML was rebuilt from the ground up with the installed Impeccable skill in Cursor (init, new-work direction roll, polish, audit/detect), running on Grok 4.5 high. It is not a paste of the marketing site. For how I have been using that model on this portfolio, see Building this blog with Cursor Grok 4.5.
Impeccable is the missing shared vocabulary: named interventions, locked product context, live iteration in the running app, and deterministic checks before the defaults land in production. This post is the builder walkthrough. For the broader skill and inspiration bookmark list, see Anti-slop design skills and inspiration pins.
Impeccable is one skill with about 23 commands, created by Paul Bakaus / pbakaus. You install a build tuned to your harness:
npx impeccable installThat path targets Cursor, Claude Code, Gemini CLI, Codex CLI, and peers. Copilot users can enable it under experimental settings. First run in a project:
/impeccable initVersion 4 is a leaner core tuned for frontier models, with clearer visitor modes and pages that commit to a direction instead of hovering in safe mid-tones.
The useful idea is not “another frontend prompt pack.” It is a language you share with the agent: /polish, /distill, /audit, /typeset, and the rest. Each name one kind of intervention.
Without project context, design skills invent a new system every session. Impeccable expects two files:
/impeccable init gathers that once. /impeccable document can reverse a DESIGN.md from an existing codebase when you already have tokens and components. Later commands read both files before they touch UI.
That is how you keep Win95 sharp corners, celestial glass, or a sober agency palette from getting overwritten by the model’s favorite radius and purple.
Impeccable names what the surface is for before it designs:
| Mode | Job |
|---|---|
| Persuade | Win attention and move someone to act |
| Operate | Help someone finish a task |
| Read | Build understanding |
| Experience | Let the work lead |
A marketing hero and an on-call dashboard should not share the same density, motion, or CTA weight. Mode is judged from the page, not only from what the company sells, so one product can hold all four.
The demo landing for this post is Persuade: one idea, one hierarchy, one primary CTA, and no card soup above the fold.
You do not need every verb on day one. Group them by job.
Setup and system
init: interview and write PRODUCT / DESIGN contextdocument: extract DESIGN.md from code you already haveextract: pull repeated patterns into tokens and primitivesshape / craft: plan or build with the vocabulary loadedQuality
critique: hierarchy, clarity, emotional fitaudit: a11y, performance, responsive gapspolish: final pass inside the existing systemharden: overflow, empty states, edge casesonboard: first-run and activation pathsAmplitude
bolder / quieter: push or restrain presencedistill: strip to the one ideaLive
/impeccable live: open the running app, pick an element or steer the page, generate variants, write the winner to sourceDay-to-day loop I would run on a section route:
/impeccable audit the surface/impeccable distill if the page is doing three jobs/impeccable polish before mergeImpeccable ships on the order of 60 deterministic detector rules (the site also cites a mid-50s check set depending on build). Examples of tells it is meant to catch: AI beige, italic serif display on soft cream, nested cards, side-tab accent borders, decorative pulsing status dots, equal feature triplets.
Those checks show up in three places:
npx impeccable detect src/ with JSON and exit codes for PR gatesThat is production discipline. Taste without a gate still ships the model default when you are tired.
Ask a model to “be creative” and it often rebuilds its favorite layout. Impeccable can deal human-reviewed visual worlds as challengers: complete graphic systems with their own laws. The winner takes the build. Treat this as a direction tool for greenfield marketing work, not a requirement for every dashboard polish.
This portfolio is Astro 7, React islands, Tailwind tokens, and theme modes that already ban a lot of AI chrome. Impeccable fits as:
/projects, /contact) without inventing a second brandI still pin inspiration boards for section order and proof placement. Skills stop the default look. Boards stop blank-page guessing. That split is spelled out in the anti-slop bookmark post. Impeccable is the vocabulary and enforcement layer on top.
Open the Lexicon demo landing in a new tab. It is a self-contained HTML page (skip link, landmarks, focus styles, reduced-motion) built as a drum-machine step-row world: named Impeccable commands as punchable steps, silkscreen labels, and a chase light for “now.” Rebuilt with the installed Impeccable skill in Cursor (npx impeccable install, /impeccable init, new-work direction seed, polish, impeccable detect), with Grok 4.5 high as the model in session. Not affiliated with the Impeccable product. Inspired by the workflow on impeccable.style.
Named interventions plus locked context plus detector gates turn agent speed into intentional UI. If your coding agent only “makes it look nice,” you will keep shipping the same page with different copy. Give it a vocabulary, then make the checks fail the PR when the tells return.
If you want help shipping a production web app with intentional UI, start on the contact page.
Moonshot shipped Kimi K3 in mid-July. A few days later, Axios reported that the Trump administration is weighing moves that could lock US companies out of cutting-edge Chinese AI models. I covered the model itself in Kimi K3 vs Claude Fable 5 and GPT-5.6 Sol. This post is the other half of the story: access risk, price, and whether a coding seat lasts a real work week.
I am not writing this as geopolitics theater. For product and agency work, three questions matter. Can you still call the model? Does the API bill stay sane? Does the subscription meter leave you mid-sprint with nothing left?
Open-weight Chinese models from DeepSeek, Moonshot, and the Qwen lineage closed a lot of the quality gap while US labs kept flagship prices high. K3 sits near Claude Fable 5 and GPT-5.6 Sol on independent composites, ships a 2.8T-class MoE, and undercuts closed flagship token rates. That combination is exactly the competitive shock Washington is reacting to.
The security story runs beside the performance story. Reporting around the Axios piece describes officials highlighting backdoors, governance gaps, and liability for companies that host or depend on Chinese open-source stacks. You do not need an outright ban for that narrative to change procurement and risk review inside US firms.
The toolkit under discussion, summarized by Axios and secondary outlets such as ChosunBiz, looks gradual rather than dramatic:
As of writing, there is no formal ban. The point of these levers is a chilling effect. US companies drop Chinese models because the compliance and political cost rises, not because the weights suddenly disappear from GitHub.
There is also a counter-voice inside the same administration orbit. David Sacks and other pro-competition voices have argued that limiting American access to tools Chinese models already handle makes the US less competitive. Attribute that as a live policy fight, not a settled fact.
API list prices still explain why US teams reached for Chinese open models in the first place. Approximate cache-miss input and output rates per million tokens (verify on the vendor pages before you budget):
| Model | Input | Output |
|---|---|---|
| DeepSeek V4 Pro | $0.435 | $0.87 |
| Kimi K3 | $3 | $15 |
| GPT-5.6 Sol | $5 | $30 |
| Claude Fable 5 | $10 | $50 |
DeepSeek sits in a different price band entirely. K3 is still roughly half the closed flagship token cost while competing on coding and agent boards. Open weights add another path: teams with GPUs can self-host and escape per-token bills after the download ships. Moonshot promised K3 weights by late July; that path matters as much as the API sticker.
Sticker price is not the same as usable capacity on a membership seat. Kimi Code membership docs describe two meters that catch heavy users:
That dual system is easy to misunderstand. One meter is a hard weekly stop. The other feels like intermittent 429s mid-session until the window rolls. CLI /usage, the Code Console, and the web membership page also do not always show the same numbers, which makes it harder to plan a day of agent work.
Kimi’s consumer ladder runs Moderato ($19/mo) through Vivace ($199/mo), with Allegro at $99/mo as a common power-user seat. On paper that looks durable. In practice, Allegro users report burning weekly quota in a few days of intensive coding, and the 5-hour throughput window can interrupt long agent loops before the weekly meter is empty.
Extra Usage exists as a paid escape hatch. Once enabled, overage bills closer to Open Platform API rates. That rescues a blocked sprint, but it also turns the “cheap Chinese seat” story into metered spend the moment you hit the wall.
I already wrote about Kimi membership latency and capacity pain in the K2.5 era in the benchmarks post. The same lesson applies to K3-era plans: a model that wins boards still fails the workday if weekly and 5-hour meters empty while you are shipping.
OpenAI bundles Codex into ChatGPT plans. Plus sits around $20/mo with Codex across web, CLI, IDE, and related surfaces. Pro adds 5x or 20x usage at $100 or $200/mo. One bill covers chat and the coding agent, and the upgrade ladder is clear when you need more headroom.
That is the generosity argument builders make in plain language. Heavy agent users often pay for Pro so a long multi-file loop does not die mid-session on a dual weekly-plus-5-hour meter. The stack is also already standard for many US-facing client projects, which reduces compliance friction if Chinese-model access gets colder.
Fair balance: ChatGPT Plus can exhaust on a heavy coding day too. Generosity is relative. People who prefer Codex are usually comparing power-user burn rates and reset behavior, not reading Plus marketing copy as unlimited. Claude Max is the other common “pay for headroom” lane at a similar $100/$200 shape; the point is usable capacity, not brand loyalty.
If your week is long agent loops, parallel tasks, and few interruptions, a more generous US coding seat can beat a cheaper Chinese membership that empties by Wednesday. If your week is bursty API volume on well-scoped jobs, Chinese token prices (or self-host after weights ship) can still win.
Treat the Kimi K3 moment as three layers, not one headline:
For client and agency delivery, keep the same test I use on every release: one real multi-file task with tools, constraints, and a deadline, plus an honest check of whether the seat lasts the week. Leaderboards and geopolitics both matter. Delivery still decides.
If you want help picking a model stack that still ships under real usage and compliance constraints, start on the contact page.
Coding agents ship working UI fast. They also ship the default look even faster: purple gradients, Inter heroes, three identical feature cards, and centered everything.
More mood boards alone do not fix that. What I pin for client and portfolio work is a two-layer stack: rules the agent must obey, then references that teach structure. This post is that bookmark page.
I start with two agent-native design skills. Both install as portable SKILL.md packs that Cursor, Claude Code, Codex, and peers can load.
Hallmark (Together AI / Nutlope) picks a layout family first, dresses it with a theme, then runs slop-test gates before it ships. The useful part for real work is the verb set: build by default, then study a URL or screenshot into a portable design brief, audit an existing page, or redesign with different bones.
npx skills add nutlope/hallmarkTaste Skill is the broader anti-slop pack I reach for when the brief needs a declared design direction, variance, and a hard pre-flight check. Default install is v2 design-taste-frontend, with companion skills for GPT/Codex, image-to-code, redesign audits, minimalist, and brutalist directions. Several of those variants already live in this repo under .agents/skills/.
npx skills add https://github.com/Leonxlnx/taste-skill --skill "design-taste-frontend"These sit next to Hallmark or Taste Skill. They do not replace them.
baseline-ui): polish spacing, accessibility, and motion on UI you already haveSKILL.md standard that makes the packs above work across toolsWorkflow I actually use: Taste or Hallmark to set direction, ui-skills or UI Craft to clean, and never invent fake social proof or Trustpilot stars.
Skills stop the default look. Boards stop blank-page guessing. I pin sites that already convert in the category, then rebuild the information architecture in the real stack with real copy.
Landing / launch
Product / SaaS UI
Type / brand
Skills stop the default look. Boards stop blank-page guessing. Together they turn agent speed into intentional UI instead of another purple gradient landing page.
If you want help shipping a production web app with intentional UI, start on the contact page.
Moonshot AI released Kimi K3 on July 16, 2026. I am writing this the next day, with the same builder lens I used for Grok 4.5: not “who won the internet,” but what I would actually put on a long agent loop for product and agency work.
Moonshot’s own launch post says the quiet part out loud. Overall performance still trails the strongest proprietary models, Claude Fable 5 and GPT-5.6 Sol. That honesty is useful. It frames K3 as open-scale frontier competition, not a magic takeover.
Kimi K3 is a 2.8-trillion-parameter mixture-of-experts model. Moonshot activates 16 of 896 experts per token, ships a 1,048,576-token context window, and treats vision as native input. The API model id is kimi-k3. Full weights are promised by July 27, 2026; the API and consumer products are live now.
Two product variants matter for builders:
Architecture notes from the launch materials include Kimi Delta Attention for long-context decode, Attention Residuals for training efficiency, and Stable LatentMoE. Treat the biggest speed and efficiency claims as vendor claims until the technical report ships with the weights.
Agent Swarm is the feature I care about most for real delivery work. Moonshot’s Agent Swarm docs (built through the K2 line and carried into K3 Swarm Max) describe an orchestrator plus specialist sub-agents that can run in parallel.
What the docs and launch case studies emphasize:
That shape matches how I already ship AI features: research a codebase or domain, fan out tools, then merge results into one coherent change. OpenAI’s GPT-5.6 Sol ultra mode is a closed-stack cousin (a handful of parallel subagents by default, more on some evals). K3’s bet is open scale plus swarm orchestration at lower token cost.
Independent composites put K3 right behind the two closed flagships. On Artificial Analysis Intelligence Index v4.1 around launch week:
| Model | Intelligence Index |
|---|---|
| Claude Fable 5 | 59.9 |
| GPT-5.6 Sol | 58.9 |
| Kimi K3 | 57.1 |
Moonshot’s launch table (max reasoning effort) and Arena preference boards show a sharper split by task type.
| Area | K3 | Fable 5 | GPT-5.6 Sol |
|---|---|---|---|
| Frontend Code Arena (Elo) | 1679 (#1) | 1631 | 1618 |
| Program Bench | 77.8 | 76.8 | 77.6 |
| SWE Marathon | 42.0 | 35.0 | 39.0 |
| BrowseComp | 91.2 | 88.0 | 90.4 |
| AutomationBench | 30.8 | 29.1 | 29.7 |
| Terminal-Bench 2.1 | 88.3 | 84.6 | 88.8 |
| Area | K3 | Fable 5 | GPT-5.6 Sol |
|---|---|---|---|
| DeepSWE | 67.5 | 70.0 | 73.0 |
| FrontierSWE (dominance) | 81.2 | 86.6 | 71.3 |
| HLE-Full (no tools) | 43.5 | 53.3 | 44.5 |
| HLE-Full (with tools) | 56.0 | 63.0 | 58.0 |
| GDPval-AA v2 (Elo) | 1668 | 1760 | 1748 |
| GPQA-Diamond | 93.5 | 92.6 | 94.1 |
Reading that as a builder: K3 looks strongest on long-horizon coding, web research, frontend preference, and cost-sensitive agent loops. Fable 5 still owns several hard reasoning and knowledge-work boards. Sol edges several coding and STEM rows by small margins.
API pricing at launch (cache-miss input / output, per million tokens):
| Model | Input | Output |
|---|---|---|
| Kimi K3 | $3 | $15 |
| GPT-5.6 Sol | $5 | $30 |
| Claude Fable 5 | $10 | $50 |
K3 also advertises aggressive prefix-cache hits on coding workloads, which matters more than list price once an agent is looping on the same repo context.
Membership is separate from API billing. Kimi’s consumer plans use musical tempo names (Adagio free, then Moderato, Allegretto, Allegro, Vivace). Current list prices live on the membership pricing page. Allegretto is $39/mo monthly or about $31/mo on annual billing today.
About four months ago, during the Kimi 2.5 era, I subscribed to a paid Kimi plan in that ~$30 USD range. On paper it looked like a solid mid-tier seat for long chats and agent work. In practice the product felt slow, and it often seemed like the service was hitting capacity limits. Capability on a leaderboard does not matter if you are waiting on a queue when you need to ship. That history is why I am watching K3 Swarm Max and API capacity as closely as the benchmark tables.
Kimi 2.5 also shows up inside my daily IDE stack. Cursor’s Composer 2.5 is built on the same open-source Moonshot checkpoint as Composer 2: Kimi K2.5. Cursor then runs continued pretraining and large-scale reinforcement learning on top, so Composer is not a raw Kimi wrapper, but the base lineage is explicit. Cursor’s own forum announcement repeats the same point: Composer 2.5 builds on Moonshot’s Kimi K2.5 with Cursor’s continued training (Composer 2.5 is now live). That is part of why a Kimi K3 release still matters to me even when I am mostly working in Cursor: the open base that trained Composer 2.5 just got a much larger successor.
When I would reach for Kimi K3
When I would still pick Fable 5 or GPT-5.6 Sol
Kimi K3 is the first open 3T-class model that sits within shouting distance of Claude Fable 5 and GPT-5.6 Sol on independent intelligence rankings, while leading several agentic coding and frontend preference boards at roughly half the closed flagship token cost. Agent Swarm is the practical differentiator for multi-step shipping work, not the parameter count alone.
If you are evaluating models for AI features that have to pay for themselves in a product, try the same test I use for every release: one real multi-file task with tools, constraints, and a deadline. Leaderboards help you shortlist. Delivery decides.
If you want help shipping an AI feature or production web app with the right model for the job, start on the contact page.
Cursor and SpaceXAI released Grok 4.5 on July 8, 2026. I am writing this the next day, on the same portfolio where I just used that model to ship a real feature: the MDX blog section you are reading now.
According to the Cursor forum announcement, Grok 4.5 is Cursor’s most capable model so far, and the first one trained jointly with SpaceXAI for more than software engineering alone. It is aimed at long-running work that needs creative tool use: coding, data work, research, and other computer tasks.
Highlights from the release:
The community thread on r/cursor is where a lot of early reactions landed after the drop.
Cursor published a comparison chart across Terminal-Bench, SWE-Bench Multilingual, DeepSWE, and SWE-Bench Pro. Here is that chart:
Reading the highlighted Grok 4.5 column:
| Benchmark | Grok 4.5 | Notes |
|---|---|---|
| Terminal-Bench 2.1 | 83.3% | Nearly tied with GPT-5.5 (83.4%), ahead of Opus 4.8 (78.9%) |
| SWE-Bench Multilingual | 78.0% | Ahead of GPT-5.5 (77.8%) and Composer 2.5 (71.6%) |
| DeepSWE 1.0 | 62.0% (high) | Ahead of Opus 4.8 max (55.8%) |
| SWE-Bench Pro | 64.7% (high) | Competitive mid-pack; Fable 5 leads this row |
Benchmarks are not the whole story. What mattered for me was whether the model could stay on a multi-step Astro portfolio task without losing the IDE theme, SEO rules, and routing constraints.
I asked Cursor (running Grok 4.5) to plan an Astro blog that stayed inside this IDE chrome, not a separate marketing layout. The model researched Astro content collections, then we locked MDX so posts could embed components like callouts.
What it shipped in this repo:
src/content/blog with Zod frontmatter/blog and /blog/[slug] wired into the existing RouteId SPAblog/ folder, tab labels, and pet tipsBlogPosting schema plus llms.txt links so AI crawlers can find postsThe hard part was not “make a markdown page.” It was keeping client-side IDE navigation working while still prerendering MDX for SEO. Grok 4.5 proposed content collections for metadata, then build-time HTML templates so post bodies stay available when you switch posts without rebooting the shell.
I ran this work on Cursor Pro with the included $20 API usage bucket. By the time the blog feature and these posts were done, I had used about 6% of that quota (the dashboard sat in the single-digit range when I captured it).
Almost all of the agent work was grok-4.5-high. The usage log for that session looks like this:
Adding only the grok-4.5-high rows from that log:
| Row (approx.) | Tokens |
|---|---|
| 2.2M + 1.5M + 3.3M + 7.1M + 1.1M | 15.2M |
| 751.4K + 365.9K + 248.4K + 316.7K + 75K + 217.7K + 317.9K + 532.8K + 353.4K | ~3.2M |
| Estimated total | ~18.4M tokens |
Call it about 18 million tokens of grok-4.5-high, with a little room for rounding and any rows that scrolled off the screenshot. A few Composer rows appear in the same window, but the blog build itself was Grok 4.5 high.
For agency and product work, I care less about a single leaderboard win and more about:
That is the bar Grok 4.5 cleared on this feature. If you are evaluating models inside Cursor, try a task that spans UI, content, and SEO in one pass. That is closer to shipping than a toy prompt.
If you want help shipping an AI-assisted product feature of your own, start on the contact page.
Most stalled projects share the same pattern: unclear scope, too many tools, and no owner for launch day. A production web app needs a short path from decision to deploy.
Write one sentence for what success looks like. More leads, faster onboarding, or a store that can take payments without manual work. That sentence drives stack choices and what you cut.
Pick tools your team can host, monitor, and change. A boring stack that ships weekly beats a clever one that only the original author understands.
Document env vars, deploy steps, and who gets paged. Agencies win when the client can run the product after the build, not when the demo looks impressive for a week.
If you want help turning a brief into a live app, start on the contact page.
Business owners do not need another chatbot demo. They need features that show up in the numbers: more booked calls, fewer missed follow-ups, faster handoffs between sales and support.
Map one painful step in your funnel. Missed inbound calls, slow quote turnaround, or support tickets that repeat the same answer. That bottleneck is where AI earns its keep.
A useful first release is often a single workflow: summarize a call, draft a follow-up, or flag a risk in a transcript. Keep the UI boring. Put the intelligence where the work already happens.
Track time saved, conversion lift, or error rate. Expand only after the thin slice proves value. That is how AI projects stay funded and how agencies keep clients.
When you are ready to scope a production feature, get in touch.
portfolio / blog/muse-spark-1-3-vs-frontier-agents.mdx
Loading…
Blog post
Sep 6, 2026 · ai, meta, muse, benchmarks, agents, coding, cursor
By Sonny Nabong
Meta shipped Muse Spark 1.3 four weeks after 1.2. Here is how the benches look against Claude and GPT, why max reasoning matters, and why I still want it in Cursor.
Loading post…