# OnCallVal taxonomy

Generated from `src/oncallval/faults.py`. Tier = f(weight):
medium 2–4, hard 5–7, severe 8+.
weight = Σ fault base weights + 3 × (extra faults) + 1 × decoys.

## Fault families

| Family | Base weight | Signature | Minimal fix | Health predicate |
|---|---:|---|---|---|
| `bad_deploy` | 3 | error spike + panic logs aligned with the newest deploy | `rollback` | current version ≠ buggy version |
| `memory_leak` | 4 | mem_pct climbs since deploy, OOMKilled events, restart churn | `rollback` | current version ≠ buggy version |
| `config_drift` | 3 | config ≠ runbook recommended; family-specific error logs | `set_config` to recommended | config[key] == recommended |
| `dependency_outage` | 4 | caller logs `connection refused` to the dead endpoint; external probes down | fail caller's endpoint key to the backup | endpoint ≠ dead endpoint |
| `capacity_shortfall` | 3 | cpu pegged, 503 saturated logs, replicas < ceil(rps / runbook rps_per_replica) | `scale` to required | replicas ≥ required |
| `secret_expiry` | 3 | x509 expired logs; cert `expires_at_min` negative | `rotate_secret` | rotated_at is set |
| `poison_message` | 4 | worker crash loop naming one message id; queue shows huge redelivery count | `purge_message` | poison message absent |
| `host_failure` | 4 | one host unhealthy; every service with replicas there degrades; per-host error 55% | `drain_host` | primary service has 0 replicas on the host |

## Decoys (weight 1 each)

| Decoy | Effect |
|---|---|
| `irrelevant_deploy` | an innocent deploy on a healthy service, timestamp-correlated with the incident |
| `known_issue` | periodic WARN logs marked as a tracked known issue |
| `cosmetic_slow` | p99 elevated but within SLO on an unrelated service |

## Actions

Reads (0.2 sim-minutes, 1 budget step): `list_services`, `get_service`,
`get_metrics`, `get_deploys`, `get_runbook`, `query_logs`, `peek_queue`.

Mutations: `restart` (+2m), `rollback` (+5m), `set_config` (+1m),
`scale` (+3m), `rotate_secret` (+2m), `purge_message` (+1m),
`drain_host` (+6m), `submit_report` (ends the episode).

Budgets: medium 26, hard 32, severe 40 actions.

## Blast radius

`host_failure` degrades **every** managed service with replicas on the dead
host, not only the paged one. `dependency_outage` pages the caller, one hop
away from the true fault. Severe episodes combine two disjoint faults, both of
which must be inactive for `mitigated`.