# Publish-train rules — coupled controller/agent releases

Standing gates for every artifact publish train (agent binary + controller golden + Day-0 manifest +
floor). Each rule cites the incident that created it. The box-level backstop (rule 4) exists because
rules 1–3 are operator discipline and discipline fails; the rules stay the primary control.

## 1. Manifest before floor (the GL-1 rule, restated)

Publish and vouch the artifacts in the Day-0 manifest **before** any floor movement. A floor that
points at an unvouched (or unpublished) version bricks self-updates: boxes are told to move to a
version they cannot verify. (GL-1 supply-chain arc; see the go-live package records.)

## 2. The manifest screen carries the LIVE DB floor — save the floor field LAST

The hub's Day-0 manifest UI also persists the global floor as a DB row
(`hub_settings.min_controller_version` — `hub/internal/store/store.go`,
`GetGlobalMinControllerVersion`). **The DB row overrides the env floor and acts immediately on the
next report cycle** — it is not staged by the manifest vouch.

**Incident:** publish train 0.81/0.113 (2026-07-11,
`documentation/pilot/RUNBOOK-publish-0.81-0.113-2026-07-11.md`): the operator saved the manifest
screen with the floor field filled; the floor acted at once and controller 0.113.0 reached Peti's
box ~9 minutes **before** agent 0.81.0 — the exact forbidden skew, benign only because the box had
zero NAS shares.

**Rule:** fill the floor field **last**, in a separate save, only after rule 3's fleet check passes.

## 3. MinAgent fleet gate — HUB-ENFORCED PER-BOX since hub v0.45.0

A controller release that depends on coupled agent behavior declares `MinAgent: X.Y.Z` in its
CHANGELOG entry header line (felhom-controller convention, since v0.114.0; retroactively, 0.113.0's
effective MinAgent was 0.81.0 for the NAS add). The floor may not effectively push a box past a
controller whose MinAgent that box's agent does not yet meet.

**Hub-enforced per-box since hub v0.45.0 (the manual fleet check is retired):** the operator sets
the golden's **`MinAgent`** in the Day-0 artifact manifest (Configuration → Day-0 artifacts →
"Min agent"; blank = uncoupled release, no gating). At report-ACK time the hub compares each box's
reported `hosts.agent_version` against that MinAgent
(`store.ResolveManagedFloor`, `hub/internal/store/store.go`): agent ≥ MinAgent → the controller
floor is served; agent below MinAgent **or unknown** → the floor is **HELD** (the ACK omits the
directive) and the box is flagged on the Hosts dashboard (`floor held: agent <v> < MinAgent <w>`) —
a held box is visible, never silently stale. The operator still SETS MinAgent at manifest time; the
hub does the per-box gating. This mechanises the "agent BEFORE controller floor" ordering that rule
2's incident violated by hand.

Effective-floor visibility (same v0.45.0): the floor card shows the resolved value + its source
(DB `hub_settings` vs env `DEFAULT_MIN_CONTROLLER_VERSION`, both raw values when they differ), and
the floor save is behind a type-to-confirm dialog stating the live below-floor blast radius — so
rule 2's "the floor acts immediately" is impossible to miss.

## 4. Box-level backstop: the controller's capability gate

Since controller v0.114.0, a coupled feature entry point probes the agent's capability
(`controller/internal/agentapi/features.go` — route probe: 2xx ⇒ supported, 404 ⇒ older agent,
transport/5xx ⇒ indeterminate, never "too old") and refuses up front with an honest Hungarian
message instead of failing mid-pipeline. This turns a violated ordering into a graceful refusal —
it does **not** license sloppy trains: rules 1–3 remain the primary control.

Convention for new coupled features: add a row to the `featureProbes` table AND the `featureMinAgent`
table + a `Supports` gate call at the feature's entry point, and declare MinAgent per rule 3. Since
controller v0.115.0 + agent v0.82.0 the agent reports its version in the `X-Felhom-Agent-Version`
response header, so `Supports` decides by version comparison when the version is known and only
falls back to the route probe for header-less (≤0.81) agents — capability detection is now explicit,
not probe-inferred.
