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Anvil

Anvil — system of record for agent teams

The system of record for agent teams — a local-first, backend-neutral project-state layer for humans and AI coding agents. Anvil records requirements, tasks, claims, evidence, and reviews in SQLite plus an append-only event log, and exposes that state through a CLI (anvil) and an MCP server (anvil-mcp) that any harness can drive.

uv tool install anvil-state gets you the CLI; from there, Getting started walks a full project — init, PRD, plan, claim, evidence, done — in about five minutes.

Start here

  • Getting started — first project, end-to-end: init → PRD → plan → claim → evidence → done.
  • Where state lives — the HOME-workspace default, ANVIL_STATE_LAYOUT=local, and ANVIL_ROOT.
  • Authoring a PRD and the PRD template — the input format, including the strict RNNN requirement-ID rule.
  • Using anvil on any harness — wire the MCP server into Claude Code, Codex, Cursor, VS Code, Zed, and more with one command.
  • Coordinating a milestone bundle — keep integration in one coordinator loop, use bounded delegation, and recover stalled or replanned work without losing history.
  • FAQ — installing, storage, backups, and common gotchas.

The core ideas

  • Claims are enforced, not conventional. A claim is a database row with a lease and heartbeat; single-winner coordination spans sessions, loops, and machines. Stale leases are reaped at queue and coordination entry points.
  • Status is downstream of proof. Completion is evidence-gated: agents submit structured evidence (typed command/diff/link proofs), reviews gate acceptance, and every accepted task mints a signed, portable AcceptanceProof verifiable off-host with anvil proof verify.
  • Everything replays. Every mutation appends to events.jsonl; replaying the log reconstructs the database — the audit guarantee is tested in CI on every PR.

Reference

The CLI reference covers every command and exit code; the MCP reference documents all 36 tools (24 on the wire by default — see its tool-surface gating section). The architecture guide maps the layers; the design doc records the trade-offs.

Project

Planning lives in the roadmap, the prioritized backlog, and the strategic backlog; the production-readiness plan sequences current work. Release history is in the repository's CHANGELOG.