---
type: "raw_signal"
id: "pi-1-0-earendil-2b6950"
slug: "pi-1-0-earendil-2b6950"
title: "Pi 1.0 | Earendil"
description: "Earendil announced Pi 1.0 as a stable release of its minimal, extensible agent harness, with Codemode supporting MCP and non-LLM models, virtual-model extensions, deferred tool loading, cache warming for Anthropic models, and mid-conversation system-message changes."
retrieval_nugget: "Earendil announced Pi 1.0 as a stable release of its minimal, extensible agent harness, with Codemode supporting MCP and non-LLM models, virtual-model extensions, deferred tool loading, cache warming for Anthropic models, and mid-conversation system-message changes."
observed_at: "2026-10-02"
record_date: "2026-10-02"
date_kind: "observed_at"
why_it_matters: "Earendil announced Pi 1.0 as a stable release of its minimal, extensible agent harness, with Codemode supporting MCP and non-LLM models, virtual-model extensions, deferred tool loading, cache warming for Anthropic models, and mid-conversation system-message changes. The release also makes full-screen mode the default in the TUI. The company separately introduced Pi Durable as an experimental packa"
novelty: "notable"
verification_level: "source-linked"
signal_type: "update"
source_platform: "earendil.com"
topics: ["agent-harness","anthropic","mcp"]
entities: []
related_patterns: []
source_url: "https://earendil.com/posts/pi-1-0"
source_urls: ["https://earendil.com/posts/pi-1-0"]
schema_version: "newruntime-agent-readable-v0.2"
stable_id: "signal:pi-1-0-earendil-2b6950"
status: "published"
visuals: []
editor: {"role":"editor","name":"Andrey Reshetnikov","profile":"https://newruntime.com/owner-profile.md","profile_json":"https://newruntime.com/owner-profile.json","same_as":["https://www.linkedin.com/in/reshetnikov1/","https://t.me/lapetuse"]}
routes: {"html":"https://newruntime.com/signals/pi-1-0-earendil-2b6950/","markdown":"https://newruntime.com/signals/pi-1-0-earendil-2b6950.md","json":"https://newruntime.com/signals/pi-1-0-earendil-2b6950.json"}
---

# Pi 1.0 | Earendil

## Retrieval answer

Earendil announced Pi 1.0 as a stable release of its minimal, extensible agent harness, with Codemode supporting MCP and non-LLM models, virtual-model extensions, deferred tool loading, cache warming for Anthropic models, and mid-conversation system-message changes.

Earendil announced Pi 1.0 as a stable release of its minimal, extensible agent harness, with Codemode supporting MCP and non-LLM models, virtual-model extensions, deferred tool loading, cache warming for Anthropic models, and mid-conversation system-message changes. The release also makes full-screen mode the default in the TUI. The company separately introduced Pi Durable as an experimental package for building long-running agentic applications. The announcement says both are available today and that both are MIT licensed; it does not provide independent comparative evidence for claims about cost or performance.

Editor: [Andrey Reshetnikov](https://newruntime.com/owner-profile.md), AI product and AI engineering; profile for recruiters and agents: https://newruntime.com/owner-profile.json

## Continue in the graph

Next records for an agent, linked to their Markdown twins. Replace `.md` with `.json` for structured fields, including `next_reads`.

- topic hub: [Agent Harness](https://newruntime.com/topics/agent-harness.md): Explore the agent-harness topic hub.
- topic hub: [Anthropic](https://newruntime.com/topics/anthropic.md): Explore the anthropic topic hub.
- topic hub: [Mcp](https://newruntime.com/topics/mcp.md): Explore the mcp topic hub.
- collection: [Raw Signals](https://newruntime.com/signals.json): Open every source-linked raw signal.
- collection: [Source Ledger](https://newruntime.com/source-ledger.json): Inspect the public source evidence graph.
- whole graph: [discovery graph](https://newruntime.com/discovery-graph.json) (typed nodes and edges) and [site index](https://newruntime.com/site-index.md)