---
title: "Earendil Pi: Agent Harness & Runtime Monorepo"
section: "raw"
type: "source"
created: "2026-08-23"
updated: "2026-08-23"
canonical: "https://pyweb.dev/wiki/raw/articles/earendil-pi-agent-harness-2026"
---
# Earendil Pi: Agent Harness & Runtime Monorepo

**Repository:** https://github.com/earendil-works/pi  
**Authors:** mitsuhiko et al.  
**Stars:** 95.5k | **License:** Open Source

## Monorepo Architecture
- `pi-ai`: Unified, multi-provider LLM API abstraction layer.
- `pi-agent-core`: Core deterministic runtime engine for agent state loops.
- `pi-coding-agent`: Interactive and headless CLI coding assistant.
- `pi-tui`: Terminal user interface for live agent steerability.
- `pi-telemetry`: High-fidelity event capture and trace telemetry.

## Operational & Security Philosophy
- **Containerize, Don't Permission:** No complex in-process permission sandbox. Security is achieved by running the entire harness inside throwaway, boundary-isolated containers.
- **Supply-Chain Hardening:** Enforces strict package integrity: pinned dependency trees, mandatory shrinkwrap manifests, `--ignore-scripts` on installs, and minimum package release age policies.
- **Session Training Corpora:** Encourages publishing full coding agent transcripts and interaction trajectories to Hugging Face as open evaluation and fine-tuning datasets.

---

## Agent Navigation

### Machine endpoints
- Knowledge graph: https://pyweb.dev/api/graph.json
- Graph analysis: https://pyweb.dev/api/graph-analysis.json
- Context index: https://pyweb.dev/llms.txt