Add provider-context prefix preparation and optional summary request settings needed by cache-friendly compaction. Existing AgentSession callers continue to pass undefined, so standalone summarization remains the default until the feature is wired in.
session_before_compact and session_compact now carry
reason ("manual" | "threshold" | "overflow") and willRetry, matching
what the RPC protocol already exposes via auto_compaction_start/end.
Extensions can now distinguish manual /compact from threshold
auto-compaction and overflow recovery through the public API instead
of monkeypatching AgentSession internals.
- New compaction.md covers auto-compaction and branch summarization
- Explains cut points, split turns, data model, file tracking
- Documents session_before_compact and session_before_tree hooks
- Rewritten hooks.md matches actual API (separate event names)
- Correct ctx.ui.custom() signature (returns handle, not callback)
- Documents all session events including tree events
- Adds sessionManager and modelRegistry usage
- Updates all examples to use correct API
pi-ai:
- Fixed usage.input to exclude cached tokens for OpenAI providers
- Previously input included cached tokens, causing double-counting
- Now input + output + cacheRead + cacheWrite correctly gives total context
coding-agent:
- Session header now includes branchedFrom field for branched sessions
- Updated compaction.md with refined implementation plan
- Updated session.md with branchedFrom documentation
