Pi Coding Agent

Pi Coding Agent is a free, open-source terminal-based coding agent from Earendil Inc that connects to 15+ AI providers. You can swap models mid-session, build custom workflow extensions, and self-host the entire stack on your own machine without vendor lock-in.

Earendil Inc designed Pi as a minimal, extensible tool: the core stays small while the extension architecture lets you script new behaviours in plain prompt templates. You bring your own API keys or run local models via Ollama, so costs scale with usage rather than per-seat subscriptions.

Features:

• •Multi-Model Switching Swap between Anthropic, OpenAI, Google, Azure, Bedrock, Mistral, Groq, Cerebras, xAI, Hugging Face, Ollama, and more without restarting your session.
• •Extension System Install community-built packages from pi.dev/packages or write your own skills and prompt templates to customise agent behaviour for your project.
• •Four Operational Modes Run Pi in interactive TUI mode, print/JSON mode for scripting, RPC mode for integrations, or SDK mode for programmatic control.
• •Git Workflow Automation Automate commit and push processes directly from the terminal so routine version control tasks run on autopilot inside the same agent session.
• •MCP Support Connect external tools and data sources via the Model Context Protocol for deeper integration with your development environment.
• •Browser Extension Use Pi's browser extension to bring the coding agent into web-based workflows alongside your terminal sessions.
• •Local Model Support And Self-Hosting Run models entirely offline using Ollama, and self-host the agent on your own infrastructure so code and prompts never leave your machine.
• •Open-Source Codebase Pi is open-source under a permissive licence; you can inspect every line, fork it, and contribute back upstream.
• •Lightweight Terminal UI Pi stays minimal by design, skipping heavy features like built-in sub-agents and plan mode in favour of a fast, tree-structured TUI you extend yourself.

Pricing:

• •Free $0/mo, fully open-source agent with no subscription tiers or usage caps from Pi itself.
• •Bring Your Own API Keys $0/mo, supply your own keys from OpenAI, Anthropic, or Google and pay providers directly at their published rates.
• •Local Models Via Ollama $0/mo, run open-weight models entirely on your machine for zero per-token cost.

Limitations:

• •Requires terminal proficiency Pi runs exclusively in the terminal. Users who are not comfortable with CLI environments will face a steep learning curve compared to GUI-based tools like Cursor.
• •No built-in GUI There is no desktop app or web interface. All interaction happens through the TUI, which limits accessibility for non-technical users who want a visual coding workflow.
• •DIY extension building Creating custom extensions and skills requires understanding prompt templates and the extension architecture. The community package library is still growing in 2026.
• •API costs are separate Pi itself is free, but you pay LLM provider costs directly. Heavy usage across multiple providers can add up quickly depending on each model's per-token pricing.
• •Smaller community than Claude Code or Cursor Pi has fewer Reddit threads, YouTube tutorials, and Stack Overflow answers, so self-service troubleshooting takes longer than with mainstream coding agents.