[SaladDay]

Codex Subagents and hosted Skills now run with Codex's native defaults.

• A child Item type with no neutral vocabulary, such as an image view or a context compaction, is skipped as in the root projection instead of failing the Run.
• turn/start no longer sends a collaborationMode. It duplicated the thread's developer instructions and, with no instructions, injected the native Default template that a local codex exec never sends. Model and effort are frozen per Session, so nothing else is needed per Turn.
• agents.max_depth keeps the native default; the pinned API defines no depth.
• Subagent observation no longer forces hooks, plugins, code mode or multi_agent_v2 off. It only enables multi_agent and maps max_threads. Managed requirements that force code mode or multi_agent_v2 are still rejected, because their collaboration calls leave no persisted receipt.
• Hosted Skills with agents/openai.yaml or a nested SKILL.md are accepted; Codex scans Skill roots recursively and does not install Skill dependencies for this client.

Docs: subagents.md and environments.md with zh mirrors.

Tests: unit tests for the skipped child Item types, the plain turn/start and the Subagent profile. Live, Codex 0.153.4 with MiniMax-M2.7: executor reuse across cold, warm, cancelled and follow-up Turns, and a Turn that spawns a Subagent, which is observed (identity, Turns, Items and coordination).

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