The sandbox docs overclaimed a containment contract the design never makes:
"capability access is routed through cordis services, never Node built-ins,
so everything a mounted plugin does stays inspectable and disposable". The
host-realm helpers on the sandbox global (harness, console, btoa) are
reachable functions, so mount code that goes looking can reach the host realm
through one of them — accepted under the trust stance, because the ctx a
mount ultimately receives is fully privileged anyway. Reword the sandbox
module doc, the README trust stance, and the RFC sandbox-semantics section to
say exactly that: the traps and small global surface STEER honest code onto
the cordis services; they are not a security boundary.
The sandbox deliberately provides no Node API, and now says so instead of
letting a bare ReferenceError teach nothing: require, the timers, and fetch
are callable traps whose error redirects to the cordis alternative (inject:
['fs'] + ctx.fs, ['web'] + ctx.web, ['bash'] + ctx.bash, ['timer'] +
ctx.setTimeout — a fiber effect, unwound on unmount). Only function-shaped
globals are trapped; process/Buffer stay undefined so typeof feature probes
stay inert. The mount description and the demo persona state the routing rule,
and the demo mounts ctx.fs (local provider) and ctx.web (seam + keyless local
fetch provider) so agent-built plugins have real capabilities to build on.
Live-validated: a model that reached for Node setTimeout self-corrected to
inject: ['timer'] in one step and built a working ctx.web fetch tool.
New top-level packages/cordis/ group with the self-referential toolset:
cordis_inspect (services / plugin tree / tools / dynamic mounts / api / events,
the api section intersecting the generated catalog with the live service store),
cordis_mount (model-written code evaluated in a node:vm sandbox, mounted under
one cordis-dynamic group fiber as dyn-<n>), cordis_unmount (awaited disposal to
quiescence). Boundary mechanisms: dual-realm instanceof, JSON realm
normalization of dynamic tool results, marker-guarded registration, SchemaSpec
teaching errors, parse failures surfaced with the offending line + caret and a
line-scoped TypeScript hint, and the unmount-first recipe on tool-name
collisions. Config: vmTimeoutMs (schemastery, default 5000). Design record:
docs/rfc/implemented/feature/2026-07-08-self-referential-cordis-toolset.md.
The tool-catalog boot manifest, its regenerated output, and the pinned
tool-name list land here rather than with the other repo registration: the
completeness guard globs packages/*/tool-* and fails the generator (and the
core/tools spec) the moment the package directory exists.
Tianyi Cui
imccyu