pi's 0.99 series lands codemode, built-in MCP, and Sign in with ChatGPT on the road to 1.0

Three releases in two days took pi from v0.87.1 to the doorstep of 1.0: v0.99.0 and v0.99.1 landed on September 29, 2026, and v0.99.2 on September 30. Together they add codemode, built-in MCP support, and tool search to every install.

The headline of v0.99.0 is a trio of built-in extensions. Codemode lets models write JavaScript that runs in a QuickJS sandbox and calls pi’s tools — in parallel — enabled with defaultTools or --tools and configured through codemode.mode and codemode.inlineBudget. Tool search declares undeclared tools to the model on demand. MCP servers come via stdio or streamable HTTP with OAuth, configured in mcp.json (global, or per project once trusted) or through pi.registerMcpServer(), and managed with /mcp and the pi mcp commands. Extension authors also gain a tool-orchestration API surface, including exposure levels, namespaces, annotations, outputSchema with structuredContent, prepareLoadout(), and ctx.executeTool() for nested calls.

v0.99.0 also switches pi’s colors to the terminal’s own palette by default, adds Sign in with ChatGPT through /login openai, lets extensions define experimental virtual models that route each request to a different physical model, and makes Jev classifiers callable from codemode scripts with any llama.cpp model usable as a classifier.

v0.99.1, published the same day, adds GPT-6.1 Sol to the OpenAI, Azure OpenAI, and OpenAI Codex providers — and makes it the default OpenAI Codex model. v0.99.2 quiets MCP integration: servers with the default codemode exposure leave the codemode description and stop blocking the first prompt, scripts find their tools through searchTools() and the new describeNamespace(), HTTP servers can authenticate with a provider’s /login token, and /reload picks up tools newly added to defaultTools.

One day later, v1.0.0 shipped — it has its own entry in this feed.