Problem: every host/service/lxc/etc. entity_status row was permanently
stuck at 'unknown' since creation. Verified against the live DB:
metric_samples had 17,559 rows, 100% attached to type='check' probe
entities and 0% to any real monitored entity; only 25 check entities
ever had real health written. check_defs.entity_id (the probe's own
bookkeeping entity) and check_defs.target_id (the host/service actually
being observed) were both real fields, but the scheduler wrote
UpsertEntityStatus/InsertMetricSample/emitSchedulerEvent keyed by
entity_id instead of target_id — so every check ran and every result
was real, it just landed on the wrong row. This is the mechanism behind
observed drift: the agent's dashboard/health tools reported the
internal probes' state, never the actual fleet.
Change:
- scheduler.go: runCheck/resolveSignal now resolve targetID from
cd.TargetID (falling back to the check's own id if unset) and write
status/metrics/events there. Signals stay keyed by the check entity,
unchanged, matching their existing resolution logic.
- Added a staleness sweep to housekeeping(): an entity whose last
observation is older than 3x its fastest enabled check's interval
(floor 5m) is marked 'stale' and emits health.stale, so a stalled
scheduler or disabled check_def can no longer look like current data
forever.
- migrations/016: deletes the now-orphaned check-entity entity_status
rows so dashboard/fleet-health rollups stop double-counting probes as
monitored entities. Historical metric_samples on check entities are
left as-is (time-series data, not safe to reattribute).
- openapi.yaml + regenerated gen code: Entity gains health/last_check_at;
'stale' added to the health enum everywhere it's used.
- dashboard.go / GetFleetHealth / nomos's get_health_summary MCP tool:
exclude type='check' entities from rollups.
- nomos/agent.go: replay prior turns' tool_use/tool_result pairs into
the conversation instead of dropping them (previously only final text
was replayed, forcing the agent to re-derive fleet state every turn),
and inject a compact live fleet-health snapshot into the system prompt
each turn so it starts oriented instead of spending an iteration on
discovery.
Risk: config_mutation (schema-adjacent — new migration, no destructive
DDL, additive DELETE only on orphaned rows). No behavior change until
oikos-api/oikos-scheduler/nomos are rebuilt and redeployed.
Verification: go build/vet clean across the repo. Ran this worktree's
own API binary against the live dev Postgres on an alternate port
(read-only from the live containers' perspective) and confirmed
/api/v1/entities now returns health/last_check_at, and the dashboard
health rollup dropped from double-counting to an honest 168 unmonitored
entities (matches reality pre-deploy — the live scheduler hasn't run
the fixed code yet). Confirmed check_defs.target_id correctly maps
multiple checks to host:hubris via direct psql query.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
After an api (MCP server) restart, nomos held a dead session id and every
tool call failed with "unexpected end of JSON input" until nomos was manually
restarted — which happens on every deploy. The MCP client now detects a
rejected session (4xx or empty body) and transparently re-initializes and
retries once. Also raise the SSE scanner buffer to 4MB so large tool results
don't exceed the 64KB default token limit.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
