docs: refresh README and agent guide

AGENTS.md

@@ -24,6 +24,9 @@ This document outlines general practices and expectations for AI agents assistin
   The `run-import.sh` script can initialize this environment automatically.
   Always activate the virtual environment before running scripts or tests.
 
+* Before committing code run `black` for consistent formatting and execute
+  the test suite with `pytest`. All tests should pass.
+
 * Dependency management: Use `requirements.txt` or `pip-tools`
 * Use standard libraries where feasible (e.g., `sqlite3`, `argparse`, `datetime`)
 * Adopt `typer` for CLI command interface (if CLI ergonomics matter)
@@ -89,6 +92,14 @@ ngxstat/
 
 If uncertain, the agent should prompt the human for clarification before making architectural assumptions.
 
+## Testing
+
+Use `pytest` for automated tests. Run the suite from an activated virtual environment and ensure all tests pass before committing:
+
+```bash
+pytest -q
+```
+
 ---
 
 ## Future Capabilities
@@ -106,3 +117,4 @@ As the project matures, agents may also:
 
 * **2025-07-17**: Initial version by Jordan + ChatGPT
 * **2025-07-17**: Expanded virtual environment usage guidance
+