Pi Coding Agent Just Got a Massive Upgrade — Fullscreen TUI, Breaking Session Model, and Transcript Search

Pi (from earendil-works) just shipped its biggest release window yet. Versions 0.84.0 (July 21) and 0.84.2 (August 14) collapse into one story: the terminal agent grew a fullscreen mode, rewrote its session backbone, and added the daily-driver polish that makes it feel like a finished product instead of a promising prototype.

If you’re new to Pi: it’s a terminal-first AI coding agent that runs on your machine, supports 20+ model providers (Anthropic, OpenAI, Google, GitHub Copilot, OpenRouter, local llama.cpp, and more), and treats your shell as a first-class tool. Think “Cursor in the terminal” but provider-agnostic and open-source.

The Headline: Fullscreen TUI Mode Finally Lands

Before 0.84.0, Pi’s terminal interface was a single scrolling pane. Now you can toggle fullscreen mode (--tui-mode fullscreen or via /settings) and get:

• A sticky editor docked at the bottom — your prompt never jumps.
• Independently scrollable transcript — review history while the agent works.
• Draggable scrollbars with auto/always/hidden modes.
• Page scrolling and marked-message navigation shortcuts.
• Stacked transient notifications that don’t cover your work.

This is the difference between “a chat in a terminal” and “an IDE in a terminal.” For beginners, it means you can finally keep context visible while the agent runs long tasks — no more losing the plan behind a wall of tool output.

How to try it: pi --tui-mode fullscreen or open /settings inside Pi and flip the TUI mode toggle.

The Breaking Change You Need to Know: Lane-Based Session Model

Pi 0.84.0 replaced its entire session architecture with a v4 lane-based model from pi-agent-core. This is a breaking change for anyone building on Pi’s SDK or extending it:

If you only use Pi as a CLI user: you likely won’t notice except for more reliable session persistence and resume. The migration is internal.

If you build extensions/SDK consumers: read the 0.84.0 breaking changes list — there are ~15 interface changes including ModelRegistry.getApiKeyAndHeaders() returning nullable headers, message_update events emitting deltas only, and provider refresh context store access replaced with generation-checked publications.

Per-Directory Context Overrides (AGENTS.override.md)

This is a quiet productivity killer feature. You can now place an AGENTS.override.md in any directory, and Pi will use it instead of AGENTS.md or CLAUDE.md in that same directory — while preserving context from parent/other directories.

Use cases:

• Monorepo: different coding standards per package
• Client work: override global rules for a specific project folder
• Experiments: test a prompt variant in one subtree without touching the main context

No more symlink juggling or environment-variable hacks. Drop the file, Pi respects it.

Configurable Default Tools (0.84.2)

defaultTools setting (global or per-project) lets you choose which built-in tools load at startup. No more waiting for the agent to discover tools you never use, or manually disabling them each session.

// mimocode.jsonc or project config
{
  "defaultTools": ["read", "write", "edit", "bash", "grep"]
}

Pair this with the new --use-theme <name> flag (0.84.2) for per-run theme overrides without changing saved settings — great for demos or pairing sessions.

Fullscreen Transcript Search (0.84.2)

Ctrl+Shift+F opens incremental fullscreen search across your entire transcript:

• Match highlighting with configurable theme colors
• Enter/Ctrl+G → next match, Shift+Enter/Ctrl+Shift+G → previous
• Works in fullscreen mode, doesn’t snap back during manual scroll
• Mouse input no longer leaks into search query

If you’ve ever scrolled back 200 turns looking for “that one error message,” this alone saves hours.

Experimental Strict JSON-Schema Constrained Sampling (0.84.2)

Enable with PI_EXPERIMENTAL=1 and the default read, bash, edit, write tools get strict JSON-schema constrained output. This means the model cannot emit malformed tool calls — the sampler enforces the schema at token level.

For beginners: fewer “tool call parsing failed” retries, faster loops, less token waste on corrections. Still experimental but a glimpse of where agent reliability is heading.

Provider & Model Updates Worth Noting

• Baseten provider built-in (BASETEN_API_KEY, defaults to zai-org/GLM-5.2)
• Kimi Coding requests now use Pi’s runtime User-Agent
• Mistral SDK transport replaced with native Chat Completions HTTP stream — less overhead, fewer moving parts
• OpenAI Responses API: deferred tool loading prefers message-anchored additional_tools
• DeepSeek API: fixed output-limit field handling, uppercase hostname detection
• Google/Vertex AI: fixed tool-call ID preservation for signed replay
• GitHub Copilot: login no longer triggers API rate limits during policy updates
• Fireworks Kimi K3: now uses OpenAI-compatible API with native reasoning-effort
• GPT-5.6 Terra/Luna pricing updated across catalogs
• Qwen Token Plan: retired qwen3.8-max-preview → qwen3.8-max

Windows & SSH Fixes That Matter

• Windows Shift+Enter detection fixed via native Win32 helper
• Truecolor detection works when Windows Terminal doesn’t pass WT_SESSION
• Keyboard input latency reduced by letting input preempt render timer
• Agent harness path handling fixed for basenames, recursive skill loading, prompt templates
• SSH Alt+Enter split input misread as Escape → fixed, plus PI_TUI_ESC_TIMEOUT for high-latency connections
• Fullscreen selection copy uses host clipboard, reports failure honestly when OSC 52 unsupported

If you’ve fought Pi on Windows or over SSH, 0.84.2 is the “it just works” release.

Extension & SDK Additions

• expandPromptTemplates option for pi.sendUserMessage() — explicitly dispatch commands, expand skills/templates
• createGatewayBindingFetch() for routing Cloudflare AI Gateway via Workers AI binding (no API token)
• AssistantMessage.endTurn preserves Codex’s end_turn signal for diagnostics
• Chainable pi.registerMarkdownTransformer() hooks for display-only Markdown transforms
• Vendor-neutral telemetry contracts with typed AI-request/harness schemas

Should You Upgrade?

How to Get It

# npm (all platforms)
npm i -g @earendil-works/pi@latest

# Or upgrade in-place
pi update --apply

Full changelogs:

• Pi 0.84.0 — breaking changes, fullscreen TUI, session model rewrite
• Pi 0.84.1 — bash tool guideline softening, worst-case latency reduction
• Pi 0.84.2 — transcript search, defaultTools, strict JSON sampling, theme flag, fixes

Related Articles

• OpenCode v1.18.18: Reliability, MCP, and Desktop Overhaul — What Changed for Beginners
• Goose v1.46: Unrolled Agent Loop, Hooks, and Cost Tracking — Beginner’s Guide
• Kilo Code v7.4.21: Agent Manager, Model Search, Worktree Upgrade — What’s New
• Hermes Agent v0.20.0 (Herald): Voice, A2A, Webhooks — Beginner’s Guide

Related articles

• Oh My Pi v17.3.3 Fixes Gemini Reasoning Loops, Hashline Edge Cases, and TUI Rendering — What Beginners Need to Know
• Claude Code v2.1.224: Self-Hosted Runners, Cross-Session Messaging, and Tighter Secret Handling
• Cline Just Made Your Coding Sessions Bulletproof — Heres What v4.1.9 Fixed

Pi is developed by earendil-works. This article covers 0.84.0 (July 21, 2026) and 0.84.2 (August 14, 2026). For the complete release history, see pi.dev/news/releases.

FAQ

Q1: What is Pi coding agent? Pi is a terminal-first AI coding agent from earendil-works that runs on your machine, supports 20+ model providers (Anthropic, OpenAI, Google, GitHub Copilot, OpenRouter, local llama.cpp), and treats your shell as a first-class tool. Think “Cursor in the terminal” but provider-agnostic and open-source.

Q2: What’s the biggest change in Pi 0.84.0/0.84.2? Fullscreen TUI mode — a sticky editor, independently scrollable transcript, and transcript search. Plus a breaking lane-based session model rewrite (v4) and per-directory AGENTS.override.md context overrides.

Q3: Is the session model change breaking for CLI users? No. If you only use Pi as a CLI user, the migration is internal — you get more reliable session persistence and resume. SDK consumers and extension builders need to update ~15 interfaces.

Q4: How do I enable fullscreen mode? Run pi --tui-mode fullscreen or open /settings inside Pi and flip the TUI mode toggle.

Q5: What are AGENTS.override.md files? Place an AGENTS.override.md in any directory and Pi will use it instead of AGENTS.md/CLAUDE.md in that directory while preserving context from parent directories. Great for monorepos and client work.

Q6: Is Pi good for Windows and SSH now? Yes. 0.84.2 fixes Windows Shift+Enter detection, truecolor detection, keyboard latency, and SSH Alt+Enter split input. It’s the first release that “just works” on Windows and high-latency SSH.

Q7: How do I install or upgrade Pi? npm i -g @earendil-works/pi@latest or pi update --apply