483e0e5edf
Codex's PR-C review found two (A) blockers: - tools/post-execute could corrupt the protected outcome. postExecute passed the mutable `result` to listeners and then read result.callId / spread result on the return paths, so a listener mutating the reference (flipping isError, rewriting callId, injecting an error) escaped the decision channel. Now the authoritative callId/isError/error are SNAPSHOT before the waterfall and the return value is rebuilt from the snapshot + the typed PostToolDecision — the decision is the only sanctioned way to change the outcome, and callId is always exec.callId. Added a regression test that mutates the result reference and asserts it has no effect; proven to fail red on the unfixed code. - Public docs/JSDoc still advertised the removed `tools/execute` waterfall after the split. Swept every current-state reference to tools/pre-execute + tools/post-execute: the ToolRegistry class JSDoc (and the regenerated catalog), loop.ts's ASCII flow (also added the prompt-submit/session-start steps it was missing), the package-map READMEs (packages, core, agent-core), core-data-structures core.md/tools.md, the bash + acp + invariants src/READMEs (the deferred permission gate is the tools/pre-execute deny/ask seam now), the cookbook, and the implemented RFCs whose factual seam catalog drifted. codec.ts's totality prose now lists `rejected`. Proposed-RFC references are left as-is (frozen proposals, validated when built).
core/ — product API spine
The packages every harness build is assembled from: the session log, the system-prompt assembly, the tool registry, the agent vocabulary, and the one concrete loop that drives them. These are product packages — the stable surface plugins and consumers build against.
| Package | Role | ctx key |
|---|---|---|
session/ |
Event-sourced session log + in-memory store | ctx.sessions |
system-prompt/ |
Prompt-section + tool-schema assembly registry | ctx.systemPrompt |
tools/ |
Tool registry + tools/pre-execute/tools/post-execute pipeline |
ctx.tools |
agent/ |
Agent interface, registry, agent/* event vocabulary |
ctx.agents |
agent-loop/ |
The concrete loop plugin: ReactLoopAgent + the loop driver |
ctx.agentLoop |
agent-core/ |
Bundle plugin: the providerless/executor-less/UI-less spine as code | (loads the spine) |
agent-loop is the one concrete implementation of the agent seam and lives here because it is the harness's default product loop; everything else in core/ is interface/vocabulary. Plugins depend on the agent vocabulary, never on agent-loop directly, so the loop stays swappable.
agent-core is the composition counterpart: one bundle plugin that loads the whole providerless spine (timer + llm + sessions + system-prompt + tools + agents + invariants + tool-bash + agent-loop) and forwards agent-loop's agents list as its own config. App packages (ui/stdio-agent, ui/acp-agent) consume it and add only a front door; a leaf adds only the swappable backends. It lives in core/ because it composes exclusively core/ + interface packages and ships no provider, executor, or UI of its own.