[SaladDay]

Records in the compatibility ledger (contracts/agents-api/index.md, EN + ZH) every remaining difference from the official service that the alignment pass left as low ROI or deliberate, so the ledger is the only list of differences.

Differences: no CORS handling; native reserved MCP labels; native handling of an unreachable MCP server; Session deletion during hosted setup; capability_directories inside /workspace only; reserved OPENAI_API_KEY in env; File name length; unknown SKILL.md front-matter keys; Credential URL stored as sent.

Known gap: Environment.files lists only the files recorded at creation.

Unverified: input to a Session whose latest Turn failed; event order when a waiting Turn resumes or is cancelled; the error for a malformed Skill version. Removed from Unverified what is now recorded: list recursion (the coverage table states it) and Credential URL normalization.

Checks: make check-docs; zh source_hash recomputed.

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