# agent-tuner > A zero-dependency CLI that stops AI coding agents from repeating mistakes. It > logs an agent's failed code generations, distills them into project-specific > rules and regression evals using your own LLM, and auto-updates your agent > config files (CLAUDE.md, AGENTS.md, .cursorrules, copilot-instructions, > Windsurf). A self-improving feedback loop tied to your codebase — not a static > prompt library. ## What it does - `npx agent-tuner init` — set up in a repo, auto-detect agent config files. - `log` — record a failed generation (what the agent got wrong + the error output). - `distill` — group failures and turn them into sharp, durable rules + one regression eval each. - `apply` — write rules into an idempotent managed block in your agent config. - `eval run` — re-run the failing prompt with the new rules; exits non-zero on regression (CI gate). ## Who it's for Small dev teams adopting agentic coding tools (Claude Code, Cursor, Copilot, Codex, Windsurf) who want their agents to stop making the same project-specific mistakes every sprint. ## Pricing - Free: 1 repo, $0, all local features. - Team: $19/mo per repo — sync rules across repos. - Org: $49/mo — org-wide shared ruleset. ## Key facts - Zero runtime dependencies; installs via npx in seconds. - Model-agnostic: works with Anthropic, OpenAI, OpenRouter, Vercel AI Gateway, LiteLLM, Ollama. - Rules and evals are git-tracked JSON your team commits and owns. - Differentiator vs prompt-library tools: rules are generated from *your* repo's real failures and are continuously regression-tested. Docs: https://tuner.aiskillhub.info