Signer agent guide

Mission

Signer validates callers, enforces Proof-of-Entitlement, and produces signed DSSE bundles for SBOMs, reports, and exports.

Advisory Handling

• Any new/updated advisory triggers immediate doc + sprint updates; no approval.
• Update high-level + detailed docs; inline only short snippets; put runnable/long code in docs/benchmarks/** or tests/** (deterministic/offline) and link.
• Add tasks + Execution Log entries in relevant SPRINT_*.md with doc paths/owners; add risks if schema/feed/transparency caps apply.
• Check archived advisories; mark supersedes/extends if overlapping.
• Defaults: hybrid reachability (graph DSSE required; edge-bundle optional), deterministic/frozen feeds; act first, report after.

Key docs

• Module README
• Architecture redirect
• Implementation plan redirect
• Canonical Attestor architecture
• Task board

How to get started

1. Open sprint file /docs/implplan/SPRINT_*.md and locate the stories referencing this module.
2. Review ./TASKS.md for local follow-ups and confirm status transitions (TODO → DOING → DONE/BLOCKED).
3. Read the architecture and README for domain context before editing code or docs.
4. Coordinate cross-module changes in the main /AGENTS.md description and through the sprint plan.

Guardrails

• Honour the Aggregation-Only Contract where applicable (see …/…/aoc/aggregation-only-contract.md).
• Preserve determinism: sort outputs, normalise timestamps (UTC ISO-8601), and avoid machine-specific artefacts.
• Keep Offline Kit parity in mind—document air-gapped workflows for any new feature.
• Update runbooks/observability assets when operational characteristics change.

Required Reading

• docs/modules/signer/README.md
• docs/modules/signer/architecture.md
• docs/modules/signer/implementation_plan.md
• docs/modules/attestor/architecture.md
• docs/modules/platform/architecture-overview.md

Working Agreement

• 1. Update task status to DOING/DONE in both correspoding sprint file /docs/implplan/SPRINT_*.md and the local TASKS.md when you start or finish work.
• 2. Review this charter and the Required Reading documents before coding; confirm prerequisites are met.
• 3. Keep changes deterministic (stable ordering, timestamps, hashes) and align with offline/air-gap expectations.
• 4. Coordinate doc updates, tests, and cross-guild communication whenever contracts or workflows change.
• 5. Revert to TODO if you pause the task without shipping changes; leave notes in commit/PR descriptions for context.