TL;DR
Get business pricing on tech for your team
- Business-only prices and quantity discounts
- Tax-exempt purchasing
- Multiple users, one account, clear invoices
Earendil has released Pi 1.0, a stable version of its minimal, extensible agent harness, with features including native MCP support through Codemode and extension support for virtual models. The company also released Pi Durable, a separate experimental package for building longer-running agent applications.
Earendil has released Pi 1.0, a hardened and extensible version of its agent harness for building and using AI agents. The release adds features including Codemode with native MCP support and extensions for virtual models; Earendil also announced Pi Durable, an experimental package aimed at longer-running agent applications.
Earendil describes Pi 1.0 as the result of months of development informed by user feedback, issues and pull requests. The company says hundreds of thousands of people use Pi each week, though it did not provide a measurement method or a more specific timeframe for that figure. It presents the 1.0 release as a stable version intended for people and businesses that rely on the software.
The release adds Codemode, described by Earendil as providing native support for MCP and non-LLM models, including Jev and image models. Other additions include extension support for virtual models, deferred tool loading, cache warming for Anthropic models, and the ability to change system messages during a conversation while accounting for the transcript and tool changes. Pi also gets a new terminal-interface theme and opens in full-screen mode by default.
Pi 1.0 is available through Earendil’s install instructions for macOS, Linux and Windows. The company says Pi and Pi Durable are MIT licensed, and that documentation is available at pi.dev, with source code hosted on GitHub. Pi Durable can be installed as an experimental package through npm; its availability does not mean it is part of the Pi 1.0 release.
New Tools Extend Pi’s Agent Workflows
The release gives Pi users more ways to combine models, tools and custom workflows without, in Earendil’s view, turning the core product into a broader or more complex platform. Codemode and virtual-model extensions are aimed at developers who want to route work among different models or connect external tools. Deferred tool loading and cache warming are also intended to change how the agent handles its available tools and model requests.
Pi Durable addresses a different need: applications that run for longer periods or are used beyond a coding session in a terminal. Earendil says the package is designed to let builders and users steer the underlying intelligence. For developers, that creates a separate experimental path to explore persistent agent applications while Pi itself retains its existing focus. The announcement does not provide performance benchmarks or independent evaluations of the new features.
Products Worth Considering
Logitech MX Master 4 for Mac, Ergonomic Bluetooth Mouse with Haptic Feedback, Ultra-Fast Scrolling, USB-C Charging, for MacOS, iPadOS, Windo
Samsung 27-inch Odyssey OLED G6 QD-OLED QHD Gaming Monitor
Amazon Kindle Paperwhite (12th Generation, 2024), 16 GB, 7-inch Display, Jade
As an affiliate, we earn on qualifying purchases.
A Minimal Harness, With Separate Durable Work
Earendil says Pi was already used as a coding agent and as a foundation for building agentic applications before version 1.0. The company’s approach, according to its announcement, is to wait for tools and techniques to prove their value before adding them, weighing functionality against added complexity. Pi 1.0’s feature list is presented as the outcome of that process, rather than an attempt to adopt every new development in agent software.
The company says some users wanted to use Pi outside the coding-agent and terminal setting, including for long-running conversations and tasks. Earendil chose to address that demand through Pi Durable rather than reshape Pi itself. It describes Durable as a new substrate that shares Pi’s stated emphasis on minimalism and extensibility, but applies those principles to longer-running applications.
“Pi does not work that way. We wait until something has proven itself, and only then do we consider adopting it; weighing its true functionality against its inherent added complexity.”
— Earendil, in its Pi 1.0 announcement
Adoption and Feature Performance Unreported
Earendil’s announcement does not include independent testing, benchmarks or detailed technical documentation for the new features, so their performance and practical trade-offs cannot be assessed from the release statement alone. The company’s figure of hundreds of thousands of weekly users is not accompanied by a methodology, geographic breakdown or comparison with earlier usage.
Pi Durable is explicitly described as experimental. Earendil has not specified in the announcement when it might leave that status, what reliability guarantees it offers, or which use cases it has tested. The source also does not state a calendar date for the release, referring to it only as happening “today.”
User Feedback and Durable Development
Pi 1.0 and Pi Durable are available now through the installation methods published by Earendil. The company says it wants feedback from users, but has not announced a timetable for further Pi releases or a milestone for Pi Durable. The next public indicators will be updates to the project’s documentation and code, along with any changes Earendil makes in response to user reports and contributions.
Key Questions
What is Pi 1.0?
Pi 1.0 is a released version of Earendil’s minimal, extensible agent harness, with added model, tool and interface features.
What new features does Pi 1.0 add?
The release includes Codemode with native MCP support, extensions for virtual models, deferred tool loading, Anthropic model cache warming, mid-conversation system-message changes, a new terminal theme and full-screen mode by default.
Is Pi Durable part of Pi 1.0?
No. Earendil announced Pi Durable as a separate experimental package for building longer-running agent applications.
How can developers get Pi?
Earendil directs users to its installation instructions at pi.dev and hosts the source code on GitHub. Pi Durable is available as an npm package, and the company says both are MIT licensed.
Source: hn
