{"schema":"postcutoff/event@1","as_of":"2026-11-13T13:49:00+01:00","url":"https://postcutoff.com/e/2026-08-05-meta-muse-code-spark-1-2/","md":"https://postcutoff.com/e/2026-08-05-meta-muse-code-spark-1-2/index.md","disclosure":{"written_by":"AI agents (Claude Opus 5.5 in Claude Code)","editor":"human editor","policy":"https://postcutoff.com/about/"},"license":null,"id":"2026-08-05-meta-muse-code-spark-1-2","date":"2026-08-05","date_precision":"day","short_title":"Meta launches Muse Code terminal coding agent powered by Muse Spark 1.2","deck":null,"takeaway":"On 2026-08-05 Meta Superintelligence Labs launched Muse Code (beta), a terminal coding agent for long-horizon software engineering, powered by a new code-focused model, Muse Spark 1.2 - Meta's answer to Claude Code, Codex CLI and Grok Build.","category":"agents","category_label":"Agents","importance":3,"confidence":"high","status":{"key":"confirmed","labels":["Confirmed"]},"sources":[{"n":1,"title":"Meta AI Research - Introducing Muse Code and Muse Spark 1.2","url":"https://research.meta.ai/blog/introducing-muse-code-and-muse-spark-1-2","type":"official","group":"primary","domain":"research.meta.ai"},{"n":2,"title":"Meta AI Developers - Meet Muse Spark 1.2 and Muse Code","url":"https://developer.meta.com/ai/resources/blog/build-with-muse-code/","type":"official","group":"primary","domain":"developer.meta.com"},{"n":3,"title":"Meta AI research blog - The multimodal intelligence of Muse Spark 1.2 (Aug 20)","url":"https://research.meta.ai/blog/multimodal-intelligence-of-muse-spark-1-2","type":"official","group":"primary","domain":"research.meta.ai"},{"n":4,"title":"WildArtifactBench preview tasks","url":"https://research.meta.ai/wild-artifact-bench","type":"official","group":"primary","domain":"research.meta.ai"},{"n":5,"title":"The Register - Meta wants to get inside your terminal with its new coding agent","url":"https://www.theregister.com/ai-and-ml/2026/08/06/meta-wants-to-get-inside-your-terminal-with-its-new-coding-agent/5283717","type":"press","group":"press","domain":"theregister.com"},{"n":6,"title":"MarkTechPost - Meta releases Muse Code (beta)","url":"https://www.marktechpost.com/2026/08/05/meta-superintelligence-labs-releases-muse-code/","type":"press","group":"press","domain":"marktechpost.com"}],"official":4,"filed":"2026-09-29","updated":"2026-09-30","orgs":["Meta"],"title":"Meta launches Muse Code terminal coding agent powered by Muse Spark 1.2","summary":"On 2026-08-05 Meta Superintelligence Labs launched Muse Code (beta), a terminal coding agent for long-horizon software engineering, powered by a new code-focused model, Muse Spark 1.2 - Meta's answer to Claude Code, Codex CLI and Grok Build. Zuckerberg later said Muse Spark 1.2's weights would be open-sourced (no date given).","key_facts":["Muse Code (beta) and Muse Spark 1.2 announced 2026-08-05","Plans, implements and validates multi-file changes across large repos using persistent async sub-agents","Local append-only event log of every model call, tool run, approval and edit - replay-exact and restart-safe","Muse Spark 1.2 also available in the Meta Model API with expanded global access","Meta demo: Muse Spark 1.2 optimized KDA and MLA kernels for NVIDIA Hopper GPUs over 1,000+ tool calls","Reported pricing: $1.25/$4.25 per 1M tokens, or $0.10/$0.20 if Meta may train on your code (MindStudio/secondary)","Reported: on 2026-08-10 Zuckerberg said Muse Spark 1.2 weights will be open-sourced, date TBD","Aug 20 follow-up (Meta research blog): Muse Spark 1.2 multimodal results 'ahead of the open-weights release'; tool use gives the largest multimodal gains; a Muse Spark variant plans tasks for a bimanual robot; Meta previewed WildArtifactBench (agent vs baseline, compared by human or agentic judges, win-rate/Elo) and released 10 of its tasks"],"key_numbers":[],"tags":["meta","msl","muse","coding-agent","cli"],"science":null,"body_md":"## What happened\n\nMSL released **Muse Code**, a CLI coding agent built around a simple agent loop plus asynchronous background agents,\nwith crash recovery via a local event log. It runs on **Muse Spark 1.2**, a coding-specialized model evaluated on\nTerminal-Bench 2.1, DeepSWE 1.1 and an internal Meta coding bench (charts only, no numbers in the post).\n\n## Why it matters\n\nEvery frontier lab now ships its own terminal coding agent; Muse Code is Meta's entry into the most commercially\nvaluable agent category of 2026.\n\nPricing and the open-sourcing pledge come from secondary sources and were not confirmed on the official post.","disputed":[],"related":[{"id":"2026-09-02-meta-muse-spark-1-3","url":"https://postcutoff.com/e/2026-09-02-meta-muse-spark-1-3/","date":"2026-09-02","date_precision":"day","short_title":"Meta releases Muse Spark 1.3 with max reasoning for long-horizon agentic work","deck":null,"takeaway":"Muse Spark 1.3 is the model generation that shipped just before Meta's consumer Muse agent (Sept 8), and it is what developers can call directly.","category":"model-release","category_label":"Model releases","importance":3,"confidence":"high","status":{"key":"confirmed","labels":["Confirmed"]},"sources":4,"official":4,"filed":"2026-09-30","updated":"2026-10-12","orgs":["Meta"]},{"id":"2026-08-10-meta-muse-glimmer-open-weights","url":"https://postcutoff.com/e/2026-08-10-meta-muse-glimmer-open-weights/","date":"2026-08-10","date_precision":"day","short_title":"Meta returns to open weights with Muse Glimmer, a 30B Apache-2.0 agentic model","deck":null,"takeaway":"On 2026-08-10 Meta released Muse Glimmer, a 30B-parameter open-weight model under Apache 2.0, optimized for local, always-on agent workflows and designed to run on a single consumer GPU or Mac.","category":"open-source","category_label":"Open source","importance":4,"confidence":"high","status":{"key":"confirmed","labels":["Confirmed"]},"sources":5,"official":3,"filed":"2026-09-29","updated":"2026-09-29","orgs":["Meta"]},{"id":"2026-08-05-meta-muse-spark-irregular-eval-breach","url":"https://postcutoff.com/e/2026-08-05-meta-muse-spark-irregular-eval-breach/","date":"2026-08-05","date_precision":"day","short_title":"Meta's Muse Spark 1.1 hacked a real website during a misconfigured Irregular cyber evaluation","deck":null,"takeaway":"Coming a week after Anthropic disclosed three Claude breaches in environments run by the same vendor, it showed that the failure lay in shared evaluation infrastructure, not in one lab's model.","category":"policy-safety","category_label":"Policy & safety","importance":4,"confidence":"high","status":{"key":"confirmed","labels":["Confirmed"]},"sources":5,"official":3,"filed":"2026-09-30","updated":"2026-10-29","orgs":["Meta","Irregular"]},{"id":"2026-07-09-meta-muse-spark-1-1-model-api","url":"https://postcutoff.com/e/2026-07-09-meta-muse-spark-1-1-model-api/","date":"2026-07-09","date_precision":"day","short_title":"Meta releases Muse Spark 1.1 and opens the Meta Model API public preview","deck":null,"takeaway":"Meta, historically a distributor of free Llama weights, now sells API access to its frontier model and competes directly with OpenAI, Anthropic and Google for developers building agents.","category":"model-release","category_label":"Model releases","importance":3,"confidence":"high","status":{"key":"confirmed","labels":["Confirmed"]},"sources":3,"official":2,"filed":"2026-09-29","updated":"2026-09-29","orgs":["Meta"]}],"people":[{"id":"mark-zuckerberg","name":"Mark Zuckerberg","url":"https://postcutoff.com/person/mark-zuckerberg/"}],"posts":[],"videos":[{"id":"theo-meta-claude-code-clone-insanely-cheap","title":"Meta's Claude Code clone is INSANELY cheap","url":"https://postcutoff.com/v/theo-meta-claude-code-clone-insanely-cheap/"},{"id":"freecodecamp-meta-muse-code-muse-spark-course","title":"Meta Muse Code & Muse Spark Course – Build AI Agents, APIs, and Full-Stack Apps","url":"https://postcutoff.com/v/freecodecamp-meta-muse-code-muse-spark-course/"}],"models":[],"changes":[{"date":"2026-09-30","type":"edit","text":"Added Meta's Aug 20 Muse Spark 1.2 multimodal post and WildArtifactBench; linked the Muse Spark 1.3 and Irregular-incident entries"},{"date":"2026-09-29","type":"filed","text":"Created"}],"provenance":{"agents":[{"model":"Claude Opus 5.5","maker":"Anthropic","tool":"Claude Code"}],"filed":"2026-09-29","run":null,"sources_read":null,"updated":"2026-09-30","human_review":null,"version":{"date":"2026-10-04"}},"gaps":[{"model_id":"gpt-6-astra","name":"GPT-6 Astra","cutoff":"2026-04","days_after":97,"in_training_data":false},{"model_id":"claude-opus-5-5","name":"Claude Opus 5.5","cutoff":"2026-06","days_after":36,"in_training_data":false},{"model_id":"gemini-4-hydrogen","name":"Gemini 4 Hydrogen","cutoff":"2026-03","days_after":127,"in_training_data":false},{"model_id":"grok-4-7","name":"Grok 4.7","cutoff":"2026-05","days_after":66,"in_training_data":false}],"short_url":null}