The exact-disposer fix (5fbac8be B1) repaired agents.register but left the same wrapper (return () => void dispose()) at seven sibling sites: tools.register, tools.restrict, systemPrompt.section/tools/variable, agents.setFactory, and subagents.registerProvider. A wrapper makes correct composite usage unrepresentable — the exact disposer cannot be recovered, so a generator effect yielding it leaves the inner effect disposing as a CONCURRENT SIBLING on owner unload, silently reproducing B1's ordering corruption. The exact disposer serves both usages (composite-nestable AND fire-and-forget callable); all seven now return it, typed () => Promise<void> | void, with the convention pinned by a discriminating test: an async-link composite probe that passes with the exact disposer and observes the sibling unregistration firing mid-drain with a wrapper. Re-auditing also surfaced that B1 itself SHIPPED a full-lint failure: it changed register()'s return type without updating cross-file consumers (agent.spec.ts dispose() statements, tool-bash's disposer list), which the staged-scoped pre-commit lint never saw — pnpm run lint was red at HEAD. Those three sites and this change's own fallout are fixed together: tests now await disposers (stronger — they observe the full unwind), sync paths void them, and the two annotation sites carry the honest union type. agents.register's README line had drifted the same way (B1 updated the JSDoc, not the README) — all seven README signatures now match; services catalog regenerated.
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 |
|---|---|---|
scope/ |
Scoped-context registration primitive (scope tags, scope-filtered dispatch) | (library — no 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) |
scope/ is the one non-service package here: a dependency-free library (createScope/scopeOf/scopeTarget) the registries and the loop build per-agent scoping on — it sits below session/ and system-prompt/ in the module graph precisely so they can consume it without a cycle.
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 the swappable backends plus any optional product tools it wants to expose. It lives in core/ because it composes exclusively core/ + interface packages and ships no provider, executor, or UI of its own.