v0.5.21

Added

• jobd_events MCP tool. The broker's event stream is the only surface that explains why rather than what: /jobs says a job is queued; only the events say it has been skipped 400 times because no worker advertises cuda-32gb. It was reachable from the CLI and the HTTP API but not from MCP. Nine tools now.

Fixed

• The MCP error model had a hole an agent falls into. JobdClient raises BrokerRefusal for any 4xx, but the rule table covered only 400/404/409 — so 401 (bad token), 403 (tailnet ACL) and 422 (malformed body) fell through to kind: "unknown" with the hint "Unmapped broker 401: …". An LLM handed that has nothing to act on and, worse, no way to know the failure is permanent, leaving it free to retry a bad token forever. All three now map to a real kind whose hint says so explicitly. A 400 with an unrecognised message maps to bad_request for the same reason: the message may be novel, but "re-sending these arguments will not work" is known. Verified against a live broker — a genuinely bad token now returns kind: auth_failed.

• The worker logged 41 diagnostics with print(..., file=sys.stderr), and systemd filed every one of them as INFO. A stderr stream gets a single journald priority (SyslogLevel=info by default), so PRIORITY=6 (info) [worker] heartbeat error: [Errno 111] Connection refused is what was actually in the journal. journalctl -p err returned nothing while the worker was failing to reach the broker at all, and no severity-based alert could ever have seen it. Now log.info/warning/error with levels chosen per message (8/10/23), and a formatter emitting systemd's <N> priority prefix — real journald priorities with no new dependency, and only when systemd is consuming the stream. Verified on a live worker: a genuine "cwd missing here; refusing admission" is now PRIORITY=4 (warning) and journalctl -p warning surfaces it.

Changed

• MCP↔broker surface parity is now DERIVED rather than remembered. tests/mcp/test_surface_parity.py reads the route table off the live FastAPI app and asserts every route is either mapped to a tool or named in _NOT_ON_MCP with the reason it should not be an agent action. A route added tomorrow that nobody exposes now fails a test instead of quietly living on one surface — the recurring drift the 2026-07-12 audit kept finding. The converse is enforced too: a registered tool covering no route fails, because every tool costs model attention (a duplicate jobd_job_get was deleted in 0.5.16 for exactly that). Same shape as the _SUBMIT_SYNTHESIZED deny-list: coverage derived, exclusions named, forgetting is what fails.