`ui-question`'s node half called `ctx.tools.register` on the host context.
`ScopedLayers.merge()` combines the global layer with the agent's exact-scope
layer, and an unscoped registration lands in the global one — so the tool
reached every agent no matter which preset composed it. `core-web`, sold as
a two-tool benchmark surface, really presented three, and a locally authored
`bash-only` preset presented two.
Rendering a question is a host UI capability; having the tool is an agent
capability, and only a preset decides that. The node half is now empty and
the `tool-ask-user` row moved into the presets that want it. The TUI keeps
its own row, having no presets.
The web composition test now asserts the global tool layer is EMPTY, which
is the invariant that would have caught this: any tool outside a preset
reaches every agent.
`dsh web` failed to boot: the aggressive plane split moved `subagents` and
its spawn/fork backends into the preset's entry-local realm, but
`dsh-host-apiproxy` is a host row that injects `subagents` to answer the
browser's cross-session queries, so it waited forever for a service only
sessions now provided. A per-session copy is wrong twice over — a provider
name registers once, so the second session would have collided anyway.
The registry and its backends go back to the host composition; the presets
keep the delegation TOOLS, which resolve that host registry. `workflows`
stays entry-local: nothing outside an agent reads it.
The web real-composition test could not have caught this, because it
disabled `api-gateway` — the very row whose pending injection names the
break. It now boots with the api-proxy enabled and the browse directory
picker substituted, so the boot audit covers the whole host-plane injection
graph. Re-introducing the old split makes it fail with the three pending
entries, which is how this was verified.
A third built-in preset: the standard coding agent plus the self-referential
Cordis toolset, a persona that explains the two-plane split, and a skill
teaching composition authoring. It exists so a person can ask an agent to
author another agent.
The skill ships INSIDE the preset directory rather than in the user's skill
root, and the root is derived from the preset's own `baseUrl` — the loader
evaluates `!!js` with `with (ctx)`, so a composition can locate itself. A
preset is the unit that gets copied and edited, so its documentation should
travel with it.
The skill leads with the rule that actually bites: a row publishing a service
may not sit loose in a preset, whether a row publishes one is not visible from
its name (`tool-bash` provides `bashEnv`), and a consumer left outside its
provider's isolate group resolves the host registry and then contributes
nothing — the quietest failure this design has.
Writing the test surfaced a consequence worth stating: an entry-local realm
makes the service invisible to the agent's own scope too, not just to the host.
Only rows inside that group resolve it, which is precisely what makes
`tool-skill` this agent's own rather than a shared one. The test asserts what
is actually observable from outside instead of reaching for the isolated
service.
TRUST: `cordis_mount` evaluates model-written JavaScript against the live
runtime, and a composition this agent writes becomes a preset other sessions
mount. Both the preset header and the toolset's own documentation say to treat
this as shell access. The tools stay opt-in per session — a test pins that they
are absent from every other preset.
