The runtime imported a bundle into its own process, which only JavaScript can be. Now an entrypoint
that is not a plain JavaScript file — or is one marked executable — is started as a child with the
runtime's environment and asked `tools/list` once and `tools/call` per call; what it lists is
registered exactly as an imported bundle's registrations are, a `<seat>.<verb>` name as the seat's
implementation. So a tools bundle may be in any language, and the mesh's part — the subjects, the
seats, the `tools` answer, a failed bundle named — stays in the runtime and is shared by all of
them. A child that exits mid-call tells the caller so and is started again on its next call.
Proven against a real bus beside the three bundles already there: a Python bundle with no SDK at
all answers its tool and its seat verb; a TypeScript bundle written against the protocol and marked
executable is served through the launcher, shortcut off; a bundle told to exit is relaunched.
One tool runtime per node, host-side, is what the runtime was written to be; the catalogue built a
container per module around it instead. This lets `serve` take a list — MESH_TOOL_MODULES as
<module>=<entrypoint> entries — and do for every assigned module what it did for one: read that
module's membership and follow it, serve its tools where the membership says, serve each held
seat's verbs on the seat's subjects. The seats come from the memberships now, so the node's
credential carries no claims; a module's own runtime still reads its credential's, so nothing
built today changes behaviour. A bare path in MESH_TOOL_MODULES stays the one-module form.
A bundle that throws on import is said in the log and in what `tools` answers for its module
(`failed`), which discovery lists with the reason instead of as "not answering"; the other bundles
serve. The filter that dropped every registration under a name but the one module goes; what
stays is that a registration under a seat's name is served only where some served module claims
the seat. A tool runs attributed to its module, so an event it emits lands on the module's
subject and not the runtime's. MESH_OPERATOR_ACCOUNT and MESH_OPERATOR_HOME are read and said;
tools take them from their environment.
Proven against a real bus: three bundles, one broken; five tools and two seat verbs answer on
their subjects; `tools` names the failed bundle; a membership re-issued mid-run re-serves.
A module implementing a seat its credential does not (yet) claim registered tools under the seat's
name; the runtime treated them as the module's own, refused to serve another module's key, and the
whole runtime restarted in a loop — postgres on the control node, 2026-10-01, whose credential predated
the claims. Such a registration is now named in the log and left out; the module's own tools serve.
The one address a runtime derives for itself is mesh.assignment.<node>.<module>. It reads the
membership there with a direct get on the ASSIGNMENTS stream, serves each tool exactly where the
membership says — the plain subject in the module's queue when the mesh issued one, this machine's
beside it — and follows the subject, re-serving when a new membership arrives. A mesh that has issued
nothing yet gets the shape it always derived, and the log says so.
A seat's verbs are the role's, not the software's (ADR 0159): a module implements them with
registerModuleTools("<seat>", …), the runtime serves that on the seat's subjects when the credential
claims the seat, and never lists it among the module's own tools. A module named like its seat
registers once and is both.
The tools answer carries each tool's subjects, and the console and CLI call the subject the listing
gave them instead of composing one.
runtime serves its seat's verbs (novox/hq ADR 0159)
A module on several machines served one subject in one queue group, so a call reached whichever
instance answered first and nobody could ask one machine's instance. Now each instance also serves
its subject with its machine as the last token, `<module>.<tool>@<node>` addresses it, and every
answer carries the machine that gave it: the console lists `node` on every module tool, strips it
into the subject, and appends "answered by <node>" to the answer; `mesh call` prints it.
And a seat's verbs are served by whoever claims the seat: the credential names the claimed seats
and the verbs each promises, the runtime serves each verb with the module's tool of the same name
on the seat's own subject, and the bus — which admits only the holder's subscription — decides where
that serving is real. Design 33 §3 and §4, built.
The runtime serves a tools verb per module with names, descriptions and schemas (design 34 §3), and
refuses a module naming its own tool tools. Discovery asks catalog_modules then each module, naming
what did not answer. One MCP handler over two transports: stdio (mesh mcp) and loopback HTTP (mesh
serve, the mesh-console module, novox/hq ADR 0152); serve refuses any bind but loopback. tools/call
may go through a running console with --console and no credential.
A module reads its broker credential from MESH_BROKER_FILE — the sealed
{url,fingerprint} the mesh delivered — and connects over amqps pinned to
exactly that certificate. The pin is two-phase (fetch cert, verify, then
trust only it), because Node's checkServerIdentity does not run under
rejectUnauthorized:false, so a naive connect-then-check would already have
sent the password to whoever answered.
A scoped module (assumeExchanges) never declares the exchanges (its account
may not) nor its own queue with a dead-letter (the broker refuses that to a
non-administrator) — the mesh pre-declared the queue, so it passively checks
it, binds and consumes. The RPC reply queue is lazy, and a module that
registered no tools serves none: a pure-events consumer touches only what its
account allows.
Verified end-to-end against a real broker as the scoped account: the audit
logger consumes # and records events, over an account that is not the
broker's own.
Claude-Session: https://claude.ai/code/session_01LrgweAeERJYBg88c5cKDzF
The per-node process that makes a module's tools serve on the mesh:
- broker-amqp.ts: a concrete AMQP implementation of the sdk's Broker
contract (request/reply over a reply queue + correlation id, publish/
subscribe over a topic exchange). Kept here, not in the sdk, so a
broker-client change never rebuilds a module (ADR 0044).
- runtime.ts: bind the broker, import the assigned modules' tool
entrypoints (each registers as it loads), serveTools. The thin wrapper.
- main.ts: the entrypoint, configured by MESH_BROKER_URL + MESH_TOOL_MODULES.
- Dockerfile: the container a node runs it as.
Verified over a REAL broker: the test spins LavinMQ (the mesh's broker),
the runtime serves a registered tool, a separate connection invokes it by
name over AMQP and gets the result, and an unknown tool is refused over
the wire. So 'modules can serve' is now running-on-the-mesh, not just
proven in a mock.
Claude-Session: https://claude.ai/code/session_01LrgweAeERJYBg88c5cKDzF
jochen
jschoubben