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 .ruff_cache/
 
 # Local opencode config
-AGENTS.md
 .agents/
 
diff --git a/AGENTS.md b/AGENTS.md
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+# API Contract Guardian
+
+## Purpose
+CLI tool that monitors OpenAPI schema diffs, detects breaking changes, generates migration guides, and gates CI pipelines on contract violations.
+
+## Build & Test Commands
+- Install: `pip install -e .` or `pip install git+https://github.com/Coding-Dev-Tools/api-contract-guardian.git`
+- Test: `pytest` 
+- Lint: `ruff check .`
+- Build: `pip wheel . --wheel-dir dist/`
+
+## Architecture
+Key directories:
+- `src/api_contract_guardian/` — Main package (CLI, diff engine, migration guide generator)
+- `tests/` — Test suite
+- `.github/workflows/` — CI/CD (4 workflows)
+
+## Conventions
+- Language: Python 3.10+
+- Test framework: pytest
+- CI: GitHub Actions (4 workflows)
+- Formatting: ruff (line-length 120)
+- Type checking: py.typed included
+- Package: setuptools with src layout
+- CLI framework: typer
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