Earendil ships Pi 1.0 with Pi Durable for crash-resumable agents

On October 1, 2026, Earendil released Pi 1.0 along with Pi Durable, an experimental package that checkpoints an agent's transcript, tool calls and model requests to storage before execution, so a new process resumes exactly where the old one stopped. Pi's core is a system prompt under 1,000 tokens and four primitive tools: read, write, edit, bash, with no plan mode, sub-agents or MCP by default.

• Pi Durable persists agent state to memory, SQLite or JSONL before running commands
• Pi core: a sub-1,000-token prompt and four tools — read, write, edit, bash
• Source without tests is about 15,000 lines, roughly 150,000 tokens for GPT
• Cloudflare shipped PiHarness in its Agents SDK the day after launch