xAI released Grok 4.6 on August 12, 2026. Cursor published a matching joint launch post the same day. I am writing 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.
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.
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. 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.
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.
DeepSeek’s July 31 note is explicit. The update upgrades only the Flash API. The V4 Pro API and the app/web models are unchanged. Quote from the changelog: “The official release of DeepSeek-V4-Pro will follow soon.”
Until that lands, deepseek-v4-pro still serves the April 24 preview. Flash 0731 currently wins several of DeepSeek’s own agent boards against that preview. My short decision guide:
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-1-2-muse-code-vs-frontier-agents.mdx
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Blog post
Aug 7, 2026 · ai, meta, muse, benchmarks, agents, coding, cursor
Meta shipped Muse Spark 1.2 and Muse Code beta. Here is how the benchmarks look against Claude, GPT, and Grok, what the UX actually is, and why I want it in Cursor next.
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