Failure Handling

Failure categories

Alloy should classify failures so users know what kind of intervention is needed.

Validation failure

The brief cannot be compiled or approved.

Examples:

• Missing source intent.
• No protected capability selected.
• No evidence plan.
• Incompatible Foundry target.

Dispatch failure

The request could not reach a runner or Foundry.

Examples:

• Runner offline.
• Foundry daemon unavailable.
• Capability manifest mismatch.

Execution failure

Foundry ran but could not complete the work.

Examples:

• Agent failed.
• Tool command failed.
• Test failure.
• Gate failure after retry.

Safety failure

The run attempted or proposed something forbidden.

Examples:

• Test weakening.
• Gate removal.
• Unauthorized mutation.
• Repository revision mismatch.

Safety failures are the enforcement edge of Security and Authority — they mark an attempt to cross a boundary that the authority model forbids.

Semantic failure

The work revealed a problem with the intent itself.

Examples:

• Two accepted intent records conflict.
• Evidence cannot be collected because the strategy is vague.
• The expected future change no longer appears plausible.

Stop conditions

Alloy and Foundry should stop, rather than continue, when:

• The brief digest does not match.
• The repository revision does not match the approved revision and no drift policy allows it.
• A required human approval is missing.
• The runner is not authorized for the project.
• A mutating request is submitted to an untrusted runner.
• The prompt pack has been edited after approval.
• A required gate is missing.
• The agent proposes weakening evidence to pass.

Several of these conditions depend on the identifiers and digest checks described in Idempotency and Correlation; a revision mismatch is what Drift Detection is designed to surface before a run begins.

Recovery patterns

Possible recovery actions:

• Recompile brief against current intent.
• Re-approve against current repository revision.
• Switch from full to dry-run.
• Narrow the formation scope.
• Ask a human clarification question.
• Mark an intent record as contradicted.
• Create a smaller repair brief.
• Re-run validation only.

Source: Integration Architecture §18 (Failure Handling).