Rewrite the agent-scope RFC with executable examples and an explicit security non-goal. Harden subagent scalar and depth validation, and pin live tool-filter semantics across code, tests, and generated docs.
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.
Every subject-extractor row of the invariants carrier table is exercised
with a matching and a foreign-keyed carrier; the HMR re-apply seed path
(sessions of agents that predate the plugin are marked started) is pinned;
the scoped tool-provider disposal, plural restrict() validation, singular
scopeHost absentee, tool-subagent passthrough, stale-stage drop, and
disposing-parent spawn (INACTIVE_EFFECT, no orphan) each gain their test.
Two genuinely defensive branches carry justified v8-ignore markers.
dsh-tools and dsh-system-prompt gain a per-scope registration layer over
dsh-scope: a registration through a scoped context files into that scope,
shadows a same-named global contribution for that scope (per-agent persona
and tool variants), and unwinds with the scope. tools.restrict() masks the
global surface per scope (snapshot-at-registration, loud unknown-name
validation, intersection composition; scoped grants bypass). One visibility
function feeds schemas/get/execute, so prompt, presentation, and dispatch
can never disagree; out-of-view executes as UNKNOWN_TOOL.
Prompt tool providers now receive the AssembleContext and return
{schemas, knownNames}: toolOrder validates against the pre-restriction name
universe (a typo fails every assembly loudly) while ordering operates on
the post-restriction schemas (a restricted-away tool is a normal absence).
dsh-session captures each session's dispatch carrier at enter() from the
entering context's scope tag, and the new sessions.flush(session) owns the
awaited session/flush dispatch. tools/pre|post-execute and
system-prompt/assemble dispatch with scope carriers keyed by their subject;
session/created|event|flush by the owning session's scope.