Tianyi Cui
7c400e9c02
Collapse docs/adr/ and docs/rfc/ into a single docs/rfc/ with proposed/, implemented/, and rejected/ subfolders. Every file is renamed to yyyy-mm-dd-topic-title.md, where the date is when the topic was first proposed (from git history). ADRs and RFCs that covered exactly the same topic are merged (property-based testing, session persistence); the umbrella RFC 005 stays split across its three implemented decisions, and RFC 006's deferred part-3 (API extractor reports) splits into its own proposed RFC. All cross-references become machine-checkable relative links instead of bare "ADR NNNN" / "RFC NNN" prose. Add a verify-md-links doc-sync gate (scripts/verify-md-links.ts) that checks every relative Markdown cross-link resolves, wired into doc-sync alongside verify-md-wrap. This makes the reorganization self-verifying: the same change that rewrote ~forty inter-doc links adds the check that proves none dangle. Document the cross-link convention in a new docs/AGENTS.md and record the gate as an implemented RFC. doc-sync, typecheck, lint, and the full test suite (667) all pass.
1.8 KiB
RFC: Event-sourced sessions with derived message history
Status: implemented (accepted 2026-06-11)
Context
The MVP requires strict event-based tracing with fully replayable sessions (严格的基于事件的trace、logging系统，session完全可回放). Two models were considered: a mutable message array with events fired as notifications (simpler, but state and log can diverge), or event-sourcing where the log IS the state.
Decision
A Session is an append-only log of typed SessionEvents — the single source of truth. The LLM message history is derived from the log (deriveMessages()); raw stream chunks are logged for token-level replay fidelity while the assembled assistant/message event is authoritative for derivation. Replay/fork = seed a new session with an existing log.
Appends are synchronous (the hot path never blocks on I/O); session/event is a sync notification; persistence plugins buffer write-behind and drain at the awaited session/flush checkpoint fired at every turn end.
Ordering contract: the loop appends to the session before emitting the corresponding Cordis event, and the agent/step-result waterfall runs before the assistant/message append so the log records what tool dispatch actually used (post-review fix; regression-tested).
Consequences
- Replay, trace, and telemetry are structurally guaranteed, not bolted on.
- Persistence stays a plugin concern; the in-memory store ships in dsh-session.
- The event vocabulary is merge-extensible (plugins add e.g. compaction events); it carries a TODO(review) marker until the first persistence plugin and real adapter exercise it.
- Derivation cost grows with log length — compaction (future plugin) is the intended mitigation, not log mutation.