Pi 1.5.1 released

A feature release adding shell authentication commands, improved cache efficiency, message threading for Anthropic, richer diagrams, and classifier model support.

What changed in 1.5.1

• Log in and out from the shell using pi auth login and pi auth logout with options for API keys and device-code sign-in.
• Prompt caches now stay warm between runs for 30 minutes when refresh costs justify it, reducing redundant cache rebuilds.
• Anthropic requests now send only new messages while the server continues conversations, falling back to full requests when context changes.
• Mermaid diagrams now include pie charts, custom styles, and clickable labels; diagrams appear in branch and compaction summaries.
• Call Microsoft-Decision-1 classifier through models.classify() for typed decisions and probabilities via GitHub Copilot.

Check before you update

• Custom GrepOperations.readFile callbacks no longer receive context lines; use grep's execute() override for remote system searches.
• OpenAI-compatible models no longer send empty tools array when tools are disabled; set compat.requiresToolsWithToolHistory: true if your proxy requires it after tool history exists.

Summarised by AgentGid from Earendil Inc. (created by Mario Zechner)'s official release notes on GitHub, as reported there; read the original before relying on it. Price, status and release dates come from our daily data.