The agent loop is back to main's tool execution: it only exports runToolCall(), honors isError results, and passes structuredContent through afterToolCall. Nested calls (ctx.executeTool, ids, events with parentToolCallId, the nestedCalls record) live in coding-agent and start on the first call.
AgentSession no longer knows exec or tool_search. Tools adjust the declared loadout through a generic prepareLoadout hook, and codemode and tool_search use it like any other tool.
exec and tool_search move to built-in extensions under src/extensions/ and register inactive (defaultActive: false). The CLI loads them with MCP; SDK sessions add createCodemodeExtension(), createToolSearchExtension(), and createMcpExtension(). Extensions gain pi.getSettings() and model catalog and classifier access on ModelRegistry.
Replaces the node:vm context with quickjs-wasi, so the sandbox is a separate wasm instance instead of a same-process V8 context. The worker stays to keep the host thread responsive; a shared interrupt flag stops spinning scripts on Bun, where worker.terminate() cannot interrupt wasm.
The Node bundle and the Bun binary build the worker as a separate entrypoint, and the Bun binary embeds quickjs.wasm.
Device authorization flow against auth.meta.com mints a Model API key via the Muse Code key-mint endpoint. Identity token stored as refresh, minted key as access; daily re-mint via the standard OAuth scheduler. Identity is non-renewable (no refresh grant), so mint 401/403 directs to /login meta. Models sourced from models.dev; default muse-spark-1.3.
Separate stable and development entrypoints, exclude remote harness code from distributions, and verify isolated consumer installs before release. Fixes#9132.
Bundle declarative plugin packages with Chord and load fresh generations. Scope client selections to persisted Session and TUI branches, and replace stale local server generations after protocol changes.
Bundle content-addressed Chord facet entries, distribute server-selected presentation artifacts during the handshake, and reload Session and TUI generations through /reload.
