pi v0.84.0: fullscreen TUI mode, Mermaid and LaTeX rendering, AGENTS.override.md

pi v0.84.0 introduces a fullscreen TUI mode that can be toggled at runtime. The new layout keeps the editor and footer sticky while letting the transcript scroll independently, and ships with draggable scrollbars so long sessions stay navigable without leaving the keyboard. The change sits on top of the existing Markdown renderer — see the UI & Display documentation for the key bindings.

The interactive transcript now renders Mermaid diagrams and terminal-friendly Unicode math inline. Mermaid blocks in your prompts, tool results, or assistant replies are drawn directly in the TUI, and LaTeX is converted to a Unicode approximation rather than relying on an external renderer. Both are configurable from the Markdown settings page.

Project-level agent configuration gets a new per-directory override file: AGENTS.override.md, sitting next to the existing AGENTS.md, lets you replace the context files that pi loads when the working directory matches. This is useful for monorepos and other multi-package repos where the same module should pick up different instructions depending on which subdirectory it is invoked from.

The release also brings a built-in Baseten provider with advanced custom-model sampling options for OpenAI-compatible endpoints, including opt-in vLLM sampling parameters. Several breaking changes ship alongside: ModelsStreamTransforms is renamed to ModelsRequestTransforms, JSON and RPC message_update events now emit deltas only, the v2 session and AgentHarness API is promoted to default, and the legacy JSONL and in-memory session repositories are removed.

Full notes, links to the affected documentation pages, and the migration guide for the renamed transforms and removed repositories are on the GitHub release page.