Introduction
What is pi?
Section titled “What is pi?”pi is the terminal-native coding agent framework. It runs in your terminal, connects to any LLM provider, and gives you full control over how the agent behaves through extensions, themes, hooks, skills, and commands.
What is tallow?
Section titled “What is tallow?”tallow is an opinionated coding agent built on pi. It bundles 31 extensions, 7 agent profiles, 34 themes, and a skill system into a single install. No manual extension management — everything ships together, ready to use.
What ships out of the box
Section titled “What ships out of the box”Extensions (31)
Section titled “Extensions (31)”Every feature is an extension. They’re organized by category:
| Category | Extensions | Examples |
|---|---|---|
| Tools (15) | Core coding tools and agent capabilities | bash, edit, read, write, cd, web-fetch, subagent, teams, tasks, plan-mode, LSP, MCP adapter |
| UI & Display (4) | Terminal rendering and status | custom footer, git status, tool display, minimal skill display |
| Commands (2) | Prompt/command system | command-prompt, command-expansion |
| Utilities (5) | Helper features | cheatsheet, context-usage, init, show-system-prompt, read-tool-enhanced |
| Integrations (1) | External system hooks | lifecycle hooks |
| Language Support (1) | IDE-like features | LSP (TypeScript, Python, Rust, Swift, PHP) |
| Context (1) | Instruction loading | context-files (CLAUDE.md + AGENTS.md) |
| Aliases (1) | Convenience shortcuts | /clear → /new |
Each extension has an extension.json manifest with a
category property that drives the documentation sidebar
and the installer’s grouping. See
Creating Extensions for
the full manifest spec.
Agents (7)
Section titled “Agents (7)”Built-in agent profiles, each with a specialized role and
system prompt. Invoke any agent as a /slash command:
| Agent | Purpose |
|---|---|
/architect | High-level architecture — plans before coding |
/debug | Methodical root cause analysis |
/planner | Read-only planning from context and requirements |
/refactor | Improve code structure without changing behavior |
/reviewer | Code review for quality and security |
/scout | Fast codebase recon for handoff to other agents |
/worker | General-purpose agent with full capabilities |
Some agents restrict their tool access (e.g. planner and
reviewer are read-only) to enforce their role.
Themes (34)
Section titled “Themes (34)”From Tokyo Night to Synthwave 84, every color in the TUI — borders, backgrounds, accents, tool status indicators — is token-driven and overridable. Create your own as a single JSON file.
Skills
Section titled “Skills”Skills are markdown-based instruction sets that the model
loads on demand when a task matches the skill’s description.
tallow supports skills from the
tallow-plugins
package system and from your own ~/.tallow/skills/ or
.tallow/skills/ directories.
Skills have frontmatter metadata including name,
description, optional allowed-tools, and optional
metadata (with fields like author, version,
argument-hint).
What makes it different
Section titled “What makes it different”- Batteries included — 31 extensions loaded automatically. No separate install step.
- Extensible from the ground up — features are extensions, not hard-coded. Don’t like how bash output renders? Replace the extension. Want a custom status bar? Write one.
- Multi-model — run Claude, GPT-4, Gemini, or any OpenAI-compatible model from the same interface.
- Multi-agent — spawn parallel agents with different models, roles, and tasks. Coordinate via shared task boards.
- Themeable — 34 built-in themes, every color token overridable. Your terminal, your palette.
- Packages — a plugin system for distributing commands, agents, skills, and hooks. Local paths only — remote repositories are not yet supported.
- Commands and prompts are interchangeable — the
commands/andprompts/directories are treated as synonyms. Files from either directory are merged into a single set, deduplicated by name. Put a markdown file incommands/orprompts/and it becomes a/slashcommand.