§7 Sense

Sense is the outbound loop: a pack announces a world change.

7.1 Declaration

1. A pack declares triggers in the manifest as stimulusTriggers: [{ ref }].
2. ref MUST be non-empty, lower-case, and MAY contain . as a separator.
3. Every ref MUST have a Policy stimuli entry with operation: read and a land (§4.4). Runtimes MUST fail lint otherwise.
4. A pack MUST NOT declare a trigger for a condition it can only obtain by polling.

7.2 Isolation

1. A trigger MUST NOT cause a command to execute.
2. A trigger MUST NOT mint credentials or bypass Binding.
3. Delivery of a trigger MUST NOT spend, send, or mutate anything outside the runtime's sink.
4. Execute and Sense MUST share the pack's Policy, Binding, and Principal scope. They MUST NOT be merged into a single tool or command.
5. A recorded trigger MAY lead an Invoker to run Execute. That Execute MUST pass the full pipeline of §6.3 under its own grants.

7.3 Grant

1. A runtime MUST NOT deliver a trigger to a sink unless the Principal holds sense.enable for the pack.
2. Without the grant, the runtime MUST acknowledge the producer and drop.
3. A runtime MUST drop a trigger whose ref the pack does not declare and SHOULD report it.

7.4 Activation

1. Sense activation MUST be independent of Execute activation. Deactivating Sense MUST NOT affect installed, activated, or connected state.
2. When activation is on, the runtime routes to a sink, either surfaced (inbox) or recorded (silent). When off, the route is drop.
3. Route selection and sink implementation are runtime concerns.

7.5 Recording

1. A sink record MUST be attributable to Principal + Binding identity + land + pack_id + ref.
2. When land is brain, the runtime MUST require project membership before surfacing the record.
3. Sink records are inert: reading one grants no capability.

7.6 Delivery mechanism

Informative. How a trigger reaches the runtime (signed ingress, vendor push mapping, message queue, a sense_only pack's stdout) is not an HCP type. Runtimes document it in their own profile.

7.7 Binding health

1. A pack with Binding mode user, local, or mothership SHOULD declare the trigger binding.degraded.
2. Its payload SHOULD carry a state from linked, stale, needs_reauth, pending, error.
3. The runtime's hub SHOULD be the producer of binding.degraded.

7.8 What is not Sense

Informative. Polling a read command; a runtime's uptime monitor; UI refresh timers; control-plane scheduler ticks. None of these are pack triggers and a runtime MUST NOT deliver them as such.

7.9 Sense-only packs

1. A pack with kind: sense_only MUST declare at least one trigger and MAY declare no commands.
2. Such a pack SHOULD have Binding public or none, and MUST NOT require a user command to install a webhook unless the upstream requires a registration call.