Agent Breaking Changes_

← Pi

Pi v0.87.1

2026-09-22 · official notes

Summary

• New Features
• Latest frontier models — Use Claude Opus 5.5, GPT-6 Sol, and GPT-6 Luna through supported providers, including GitHub Copilot. See Choose a Model.
• Grok 4.7 by default for xAI — New xAI sessions now default to Grok 4.7. See Provider Authentication.

Full notes

### New Features

- **Latest frontier models** — Use Claude Opus 5.5, GPT-6 Sol, and GPT-6 Luna through supported providers, including GitHub Copilot. See [Choose a Model](https://github.com/earendil-works/pi/blob/v0.87.1/packages/coding-agent/docs/models.md#select-a-model).
- **Grok 4.7 by default for xAI** — New xAI sessions now default to Grok 4.7. See [Provider Authentication](https://github.com/earendil-works/pi/blob/v0.87.1/packages/coding-agent/docs/providers.md#use-an-api-key-from-the-environment).

### Added

- Added inherited Claude Opus 5.5, GPT-6 Sol, and GPT-6 Luna support for GitHub Copilot.
- Added inherited GPT-6 Sol and GPT-6 Luna support for OpenAI API keys and OpenAI Codex subscriptions.
- Added inherited Claude Opus 5.5 support for Anthropic with adaptive thinking and a 1M context window.

### Changed

- Changed the default xAI model to Grok 4.7.

### Fixed

- Fixed split-turn compaction summaries being refused by Claude Fable 5.1 by clearly separating the conversation and using continuation-oriented instructions ([#9908](https://github.com/earendil-works/pi/pull/9908) by [@davidbrai](https://github.com/davidbrai)).
- Fixed missing or invalid `--mode` values being silently ignored instead of reporting an error and exiting with a nonzero status ([#9045](https://github.com/earendil-works/pi/issues/9045)).
- Fixed inherited image-only user messages being rejected by some OpenAI-compatible providers because they included an empty text part ([#9797](https://github.com/earendil-works/pi/issues/9797)).
- Fixed inherited Anthropic OAuth requests reporting an outdated Claude Code version.