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+# Agent Contributor Guide
+
+This repository is Codanna: a local code-intelligence MCP server and CLI for AI coding agents. Keep changes small, local-first, and easy to verify.
+
+## Start Here
+
+Before changing code, read:
+
+- `README.md` for product scope, supported modes, and user-facing behavior.
+- `CONTRIBUTING.md` for the short contribution workflow.
+- `contributing/README.md` and `contributing/development/guidelines.md` for Rust development rules.
+- `contributing/development/language-support.md` before parser or language-support work.
+- `.mcp_stdio.json`, `CLAUDE.md.example`, and `.codannaignore` when touching MCP integration, agent handoff, or indexing behavior.
+
+## Important Areas
+
+Be extra careful with changes to:
+
+- `src/` parser, indexing, relationship, semantic-search, and MCP code.
+- MCP stdio / HTTP / HTTPS transport behavior.
+- Document/RAG indexing and `.codannaignore` handling.
+- Embedding model download/configuration and any remote embedding opt-in paths.
+- Install scripts, release packaging, and profile/integration templates.
+- Language parser grammars or generated parser analysis files under `contributing/parsers/`.
+
+## Verification
+
+Use the existing scripts instead of inventing new checks:
+
+```bash
+cargo build --release --all-features
+./contributing/scripts/quick-check.sh
+./contributing/scripts/auto-fix.sh
+./contributing/scripts/full-test.sh
+```
+
+For small docs-only changes, at minimum run a diff/format sanity check and state that no code tests were needed. For code changes, prefer a targeted test first, then the relevant contributor script.
+
+## Pull Request Notes
+
+- Keep PRs focused on one issue or behavior.
+- Add or update tests for behavior changes.
+- Update docs when user-facing commands, MCP contracts, configuration, or language support changes.
+- Do not commit generated or cache directories such as `.codanna/` unless maintainers explicitly ask.
+- If a change affects agent integration, include the MCP/CLI command you used to verify it.