c76b7042b6
The compaction e2e never exercised compaction: its window/fixture combo (contextWindow 8000, thresholdRatio 0.5 → threshold 4000; four small files) peaked at ~1389 estimated tokens, so compactIfNeeded declined every pre-step and compact/start never landed. Shrink the window (contextWindow 2400 → threshold 1200; retainTokens 500 + summarizationMaxTokens 300 = 800 < 1200, convergence holds) and grow the fixture to six files so a couple of bash steps reliably cross the threshold. Verified compaction fires and the suite passes across repeated real-API runs. Sync docs left stale by the landed compaction work: list compaction.e2e.ts and keyless-smoke.e2e.ts in the coding-agent README (and fix the wrong "Both self-skip" count), add compaction to the examples with-key inventory, and replace the hypothetical compaction/marker / "future plugin" naming in the session README, session types JSDoc, and the core-data-structures catalog with the real compact/start, compact/summary, compact/end events.
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/execute waterfall |
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.