# Schemas

Canonical contracts for the runtime.

## Identity

| ID | Assigned at |
|---|---|
| event_uuid | sensor, at impulse creation |
| cycle_uuid | lemniscate, at cycle open |
| decision_uuid | L1 gate decision |

UUID v7. 48-bit timestamp prefix; sort order = causal order. No record enters Phoebe without causal UUIDs.

## Impulse row

`(event_uuid, gate, timestamp, payload)`

Created at sensor; UUID v7; immutable.

## Gate state row

| Field | Meaning |
|---|---|
| gate | registry name |
| window_start | aggregation window start |
| counters | per-gate counters (JSONB) |
| threshold | value shifted by L1 |
| last_opened | cycle index of last opening |
| last_decision_cycle | cycle_uuid of last shifting decision |
| l1_rtt_ewma / l2_rtt_ewma | sliding means used for cycle interval |

Stored in Phoebe; checkpointed after each cycle; restored on restart.

## Gate tag row

`(gate, tier, why, mode_overrides)`

| Field | Meaning |
|---|---|
| tier | T0 critical / T1 relational / T2 standard / T3 ambient |
| why | declared reason and audit string |
| mode_overrides | per-mode tier shifts (UUID-logged decision) |

T0/T1 registry-declared, runtime-immutable. T2/T3 may shift per mode.

## Evidence request

| Field | Meaning |
|---|---|
| request_uuid | v7, issued at L1 |
| gate | registry name, validated |
| since | cycle boundary |
| returned_from | buffer lower bound; truncation recorded |

## Message schemas

Per subsystem: gates, director, clients.

Version: 0.4 | Updated: 2026-11-04