Pi Test Harness

A test framework for pi extensions — lets you write automated tests that verify extension behavior without running a full LLM session.

Pi extensions add tool calls to the agent, but testing them is awkward: you’d need to spin up a model, craft prompts that trigger the right tools, and parse the output. Pi Test Harness provides a mock pi environment where you can call extension tools directly, assert on their outputs, and verify state changes.

Used to test Pi Planner’s plan lifecycle (propose → approve → execute → complete), Pi Safety’s glob matching, and the interaction between plan mode and tool restrictions.

Part of the pi-mf-extensions monorepo.