Nine Failure Modes (FM-01..FM-09)

ELI5

stratt ci runs nine x-ray scans on every change. Eight block the build; one (draft isolation) only flashes a warning. Each scan has a number — when CI fails, the number tells you exactly which scanner caught it.

Technical Deep Dive

Source: packages/graph/src/{ci,protect,dag}.ts, agent/SOUL.md.

The Nine Modes

Scanner Pipeline

flowchart TD
    A[stratt ci paths --council X] --> B[FM-01 verify Blake3 of every unit]
    B --> C[FM-02 resolve every import]
    C --> D[FM-03 Kahn DAG cycle detect]
    D --> E[FM-04 protected agent present per chain]
    E --> F[FM-05 gate-removal vs prior published]
    F --> G[FM-06 contract diff classification]
    G --> H[FM-07 status compatibility check]
    H --> I[FM-09 step.agent capabilities cover step requirements]
    I --> J{any blocking?}
    J -->|yes| K[exit 1]
    J -->|no| L[FM-07 warnings only? exit 0]
    B -. failure .-> K
    C -. failure .-> K
    D -. failure .-> K
    E -. failure .-> K
    F -. failure .-> K
    G -. failure .-> K
    I -. failure .-> K
    style H fill:#fef3c7
    style K fill:#fecaca

Spec Mapping

• FM-01 → SPEC-02
• FM-02, FM-03 → SPEC-03
• FM-04, FM-05 → SPEC-04
• FM-06, FM-07 → SPEC-01 (FM-07 also touches SPEC-03)
• FM-08 → publishing infrastructure (SPEC-02 atomicity)
• FM-09 → SPEC-01

Severity Semantics

• Critical — content integrity violation; the unit cannot be trusted at all.
• Blocking — protocol invariant violation; must be fixed before merge.
• Warning — flagged but does not exit non-zero; surfaces in CI logs.
• Infrastructure — outside the unit content; retry-able.

Key Terms

• Kahn’s algorithm → BFS-based DAG cycle detection used in FM-03; finds a topological order or reports the cycle.
• Blast radius → All units transitively dependent on a target; consulted by FM-06 when classifying breaking changes.
• Status compatibility → Allowed importer/imported status pairs (see grace-012).

Q&A

Q: Why is FM-07 only a warning? A: A stable unit transiently importing a draft during refactor is a real pattern; blocking would create churn. The warning surfaces the drift without halting.

Q: Where in the pipeline does FM-08 surface? A: Not during stratt ci — it is the publishing path failure (R2 unavailable). It is infrastructure-level and the publish operation is atomic so the fingerprint commit rolls back if R2 write fails.

Q: Does FM-04 fire if the protected agent is on a deprecated step? A: Presence is checked at chain composition level, not by step status. The protected agent must own at least one step in the executable composition.

Examples

A PR removes the BECK-02 reviewer step from dev/chain/sol-1-boot and edits a single task body. CI run:

• FM-01 ✓ (fingerprint recomputed)
• FM-02 ✓ (no import changes)
• FM-03 ✓ (no cycle)
• FM-04 ✗ blocking — Pathfinder protected agent BECK-02 missing.
• (FM-05 also fires if a gate step was removed)

Exit 1 with FM-04 message; merge blocked.