---
created: 2026-05-16
modified: 2026-07-28
type: note
tags:
  - ai
  - dev-ops
aliases: []
---

# Pi Agent Extensions & Skills

## Source Repositories

| Source | Location |
|---|---|
| Gitea (package) | `git:https://gitea.lab.audasmedia.com.au/sam/pi-config` |
| Local filesystem | `~/.agents/` |
| Project settings | `sys_config/.pi/settings.json`, `ai_setup/.pi/settings.json` |

---

## Extensions

| Extension | Source | Purpose |
|---|---|---|
| **pi-config** | `~/.agents` | `/config-add`, `/config-remove`, `/config-show`, `/config-setup` — manage which extensions/skills are active in a project |
| **tavily-search** | Gitea | `tavily_search` — web search via Tavily API (AI-optimized) |
| **web-fetch** | `~/.agents` | `web_fetch` — fetch any URL and return clean markdown (HTML, PDF, JS-rendered with Jina fallback) |
| **ask-user-question** | `~/.agents` | `ask_user_question` — LLM presents structured multiple-choice / text questions with keyboard UI |
| **video-extract** | `~/.agents` | `video_extract` — extract frames from YouTube/local video + full Gemini analysis (requires ffmpeg + yt-dlp + GEMINI_API_KEY) |
| **filechanges** | `~/.agents` | `/filechanges`, `/filechanges-accept`, `/filechanges-decline` — tracks every file LLM edits/writes, diff review, revert |
| **pi-prompt-template-model** | npm (global) | Model-switching prompt templates with frontmatter. See [[#Prompt Templates]] section below |
| **pi-mcp-adapter** | npm (global) | Single proxy tool (~200 tokens) replaces hundreds of MCP tool definitions. `/mcp` command for management. Lazy server connections |
| **pi-graphify** | `~/.agents` | Knowledge graph tools: build, query, path tracing, explain, watch, add, update |
| **plannotator** | `~/.agents` | Interactive plan review with browser UI, annotations, code review |
| **caveman** | `~/.agents` | Ultra-compressed communication mode |
| **markitdown** | `~/.agents` | Convert files (PDF, Word, Excel, PPTX, images, HTML, etc.) to Markdown. Image analysis via Qwen 2.5 VL 72B on OpenRouter. |
| **@tintinweb/pi-subagents** | npm (global) | 18 custom agent types, background agents, mid-run steering, session resume, worktree isolation, scheduling, cross-extension RPC. See [[Pi Subagent]] for full documentation |
| **@tintinweb/pi-tasks** | npm (global) | Task management with dependency tracking, auto-cascade, background process tracking, TaskExecute spawns subagents via RPC |
| **gentle-engram** | `~/.agents` | Memory service connecting to engram via ENGRAM_URL. Replaces memory-vault. Session capture, compaction recovery |
| **headroom-bridge** | `~/.agents` | `compress_for_agent` tool — compresses >20K chars via Headroom Docker on .13:8787. 60-95% token reduction |


### pi-subagents (@tintinweb)

v0.10.2, installed globally. 18 custom agent types in `~/.pi/agent/agents/` → `~/.agents/agents/`. Tools: `Agent()`, `get_subagent_result()`, `steer_subagent()`. `/agents` command for interactive management. Features: background agents with concurrency (4 default), mid-run steering, session resume, worktree isolation, scheduling, persistent widget showing live agent status. Cross-extension RPC event bus. Patched: 24h agent survival (was 10min), clearDisabled on session start. See [[Pi Subagent]] for full documentation.

### pi-tasks (@tintinweb)

v0.7.0, installed globally. 7 task tools: `TaskCreate`, `TaskList`, `TaskGet`, `TaskUpdate`, `TaskOutput`, `TaskStop`, `TaskExecute`. `/tasks` command. Features: dependency tracking (blocks/blockedBy), auto-cascade, background process tracking, persistent widget. `TaskExecute` spawns subagents via RPC.

---

## Skills

| Skill | Purpose |
|---|---|
| **nixos-workflow** | STRICT workflow for managing Pi assets via Gitea on NixOS |
| **system-architect** | Multi-machine NixOS infrastructure (Snapcast, MQTT, Docker, Nvim) |
| **obsidian-cli** | Interact with Obsidian vault (notes, search, plugin dev, theme dev) |
| **graphify** | Full-pipeline knowledge graph orchestration |
| **caveman** | Caveman communication mode |
| **openspec-propose** | Propose new changes with design docs, specs, tasks |
| **openspec-apply-change** | Implement tasks from an OpenSpec change |
| **openspec-archive-change** | Archive completed changes |
| **openspec-explore** | Explore ideas and clarify requirements |
| **npm-security** | Scan packages with SafeDep Vet, check typosquatting with npq, wrap installs with Socket Firewall |
| **ste-writing** | Rewrite prose (docs, READMEs, PRs, errors) into ASD-STE100 Simplified Technical English. Removes AI slop. Two modes: strict (procedures) and STE-flavored (general prose). Includes heuristic anti-slop linter (ste-lint.py). |
| **design-build** | Generate production-ready HTML/Tailwind code from design specifications and DESIGN.md design tokens. |
| **design-explore** | Generate UI design mockups as images for exploration and ideation. Supports DESIGN.md for design-token-accurate mockups. |
| **markitdown** | Convert files (PDF, Word, Excel, PowerPoint, images, HTML, CSV, JSON, XML, ZIP, EPubs, YouTube) to Markdown for LLM consumption. Image analysis via Qwen 2.5 VL 72B on OpenRouter. |

---

## markitdown

Convert various file formats to Markdown. Useful for feeding documents and images into LLMs.

### What it converts

| Format | Input | Notes |
|--------|-------|-------|
| PDF | `.pdf` | Preserves structure (headings, lists, tables) |
| Word | `.docx` | mammoth + lxml |
| PowerPoint | `.pptx` | python-pptx |
| Excel | `.xlsx`, `.xls` | openpyxl + pandas |
| Images | `.jpg`, `.png`, etc. | EXIF metadata (free) + LLM vision description (via OpenRouter) |
| HTML | `.html` | beautifulsoup4 |
| CSV / JSON / XML | `.csv`, `.json`, `.xml` | Structured data → Markdown tables |
| ZIP | `.zip` | Iterates contents, converts each file |
| EPubs | `.epub` | |
| YouTube | URLs | Transcript extraction |

### CLI usage

```bash
# Convert file to Markdown (stdout)
markitdown document.pdf

# Write to file
markitdown document.pdf -o document.md

# Image with LLM vision description
markitdown-vision photo.jpg
```

### Image analysis

Two levels:

1. **EXIF metadata only** (free, no API key): `markitdown photo.jpg`
2. **LLM vision description** (via OpenRouter, requires API key): `markitdown-vision photo.jpg`

The `markitdown-vision` wrapper auto-sources `OPENROUTER_API_KEY` from `~/.config/environment.d/10-secrets.conf` and uses `qwen/qwen2.5-vl-72b-instruct`.

### Missing / can be added

| Feature | What's needed |
|---------|--------------|
| Audio transcription | `pip install markitdown[audio-transcription]` (pydub + speechrecognition) |
| Azure AI Document Intelligence | `pip install markitdown[az-doc-intel]` + Azure credentials |
| Azure Content Understanding | `pip install markitdown[az-content-understanding]` + Azure credentials |
| markitdown-ocr plugin | Installed but needs OpenRouter key enabled to activate |

---

## falcode-zellij

Zellij plugin + agent extensions that track all active AI coding panes (pi, OpenCode, Claude Code) across Zellij sessions in a floating popup. Jump to any pane with one keystroke. Shows attention icons on Zellij tabs when an agent starts/stops working.

### Components

| Component | Location | Purpose |
|-----------|----------|---------|
| **Zellij WASM plugin** | `~/.config/zellij/plugins/falcode-zellij-sessions.wasm` | Floating popup UI showing all agent panes |
| **pi extension** | `~/.pi/agent/extensions/falcode.ts` | Reports pi pane status (working/idle) to the Zellij plugin |
| **attention WASM** | `~/.config/zellij/plugins/zellij-attention.wasm` | Shows ⏳/✅ icons on Zellij tabs when agent is active/done |
| **detection script** | `~/.local/state/falcode-zellij/` | Shared state directory for pane status snapshots |

### Keybindings

| Key | Action |
|-----|--------|
| `Alt a` | Launch/focus falcode floating popup (config.kdl `shared_except "locked"`) |

### pi integration

The `falcode.ts` extension auto-detects Zellij via `ZELLIJ_PANE_ID`/`ZELLIJ_SESSION_NAME` env vars. Outside Zellij it's a no-op.

- `agent_start` event → writes `"working"` status
- `agent_end` event → writes `"waiting_user_input"` status
- Heartbeat every 60s to keep pane alive
- `FALCODE_NOTIFY_SCRIPT=/bin/true` in home.nix (disables macOS notifications on Linux)

### Install on new machine

```bash
# pi extension
mkdir -p ~/.pi/agent/extensions
curl -L https://raw.githubusercontent.com/victor-falcon/falcode-zellij/main/pi-extension/falcode.ts \
  -o ~/.pi/agent/extensions/falcode.ts

# WASM plugins
mkdir -p ~/.config/zellij/plugins
curl -L https://github.com/victor-falcon/falcode-zellij/releases/latest/download/falcode-zellij-sessions.wasm \
  -o ~/.config/zellij/plugins/falcode-zellij-sessions.wasm
curl -L https://github.com/victor-falcon/falcode-zellij/releases/latest/download/zellij-attention.wasm \
  -o ~/.config/zellij/plugins/zellij-attention.wasm
```

### Claude Code integration

Also has a hook at `~/.local/state/falcode-zellij/falcode-hook.sh` for Claude Code status reporting. See [README](https://github.com/victor-falcon/falcode-zellij#readme) for Claude config.

### Zellij config (`config.kdl`)

Already configured in Home Manager:
```kdl
plugins {
    falcode location="file:/home/sam/.config/zellij/plugins/falcode-zellij-sessions.wasm" {
        state_dir "/home/sam/.local/state/falcode-zellij"
    }
    attention location="file:/home/sam/.config/zellij/plugins/zellij-attention.wasm"
}

load_plugins {
    "file:/home/sam/.config/zellij/plugins/zellij-attention.wasm" {
        enabled "true"
        waiting_icon "⏳"
        completed_icon "✅"
    }
}

keybinds {
    shared_except "locked" {
        bind "Alt a" {
            LaunchOrFocusPlugin "falcode" {
                floating true
                move_to_focused_tab true
            }
        }
    }
}
```

---

## Security Tools (npm Global)

Three tools installed globally at `~/.local/share/npm-global/bin/` to guard package installs.

### SafeDep Vet (`vet`)

Scans local directories for multi-language malware signatures. Catches obfuscated code, suspicious imports, base64 payloads.

```bash
# Scan a cloned repo before touching it
vet scan -D . --format json --filter "package.malware == true"

# Scan package metadata from npm registry
vet scan package <name> --format json
```

### Socket Firewall (`socket`)

Wraps npm/pip installs with real-time scanning. Blocks malicious packages at install time.

```bash
# Safe npm install
socket npm install <package>

# Safe pip install
socket pip install -r requirements.txt
```

### npq

Checks package names against typosquatting lists before install. Lightweight, local, no phoning home.

```bash
npq check <package> --json
```

### Workflow

```
1. vet scan → checks for malware in the code/package
2. npq check → checks the package name for typosquatting
3. socket install → wraps the actual install with runtime scanning
```

The **npm-security** skill instructs the Pi agent to follow this workflow before any install.


## Headroom

Headroom is a **context compression layer** that reduces prompt token usage by 60-95% for heavy analysis/code/devops workloads. It runs as a Docker container on the server (192.168.20.13) and is triggered by the headroom-bridge extension.

### How it works

1. headroom-bridge detects analysis/code/devops contexts
2. Tags `read`, `discuss`, `search` **never** trigger compression (these are fast paths)
3. For all other tags, if accumulated context exceeds ~5K tokens, headroom-bridge calls `compress()`
4. Messages are sent to the Headroom proxy at `192.168.20.13:8787`
5. Headroom compresses the context (using SmartCrusher for JSON, CodeCompressor for AST, Kompress-base ML for text)
6. Compressed messages are returned and forwarded to the LLM
7. If the proxy is down, messages pass through unchanged (graceful fallback)

### Architecture

```
Desktop (.27)                         Server (.13)
─────────────                         ────────────
headroom-bridge                       headroom proxy (Docker)
    │                                     │
    │  if compress needed:                │
    │  compress_for_agent(content) ──────►│
    │  HTTP POST 192.168.20.13:8787       │
    │  ◄────────── compressed content     │
    │                                     │
    │  return to agent                    │
    │                                     │
    │  if proxy down: pass through        │
```

### Compression thresholds

| Condition | Action |
|---|---|
| Tag is `read`/`discuss`/`search` | Skip — no compression |
| Context < 5K tokens | Skip — too small to benefit |
| Context ≥ 5K tokens + analysis/code/devops tag | Compress |
| Proxy unreachable | Pass through unchanged |

### headroom-bridge

Path: `~/.agents/extensions/headroom-bridge/index.ts`. Tool: `compress_for_agent({ content })` — compresses content >20K chars via Headroom Docker on .13:8787. 60-95% token reduction. See [[#Function Calls]] for signature.

### Management

```bash
# Check status
ssh 192.168.20.13 "docker ps --filter name=headroom"

# View logs
ssh 192.168.20.13 "docker logs --tail 20 headroom"

# Restart
ssh 192.168.20.13 "docker restart headroom"

# Update image
ssh 192.168.20.13 "cd /home/sam/Docker/Containers/headroom && docker compose pull && docker compose up -d"
```

### Files

| File | Purpose |
|------|---------|
| `~/.agents/extensions/headroom-bridge/index.ts` | `compress_for_agent` tool implementation |
| `/home/sam/Docker/Containers/headroom/docker-compose.yml` | Docker service definition (on .13) |
| `/home/sam/Docker/Containers/headroom/.env` | Environment file (on .13) |


## codebase-memory-mcp

Code intelligence MCP server by DeusData. Single static C binary (~13MB), zero dependencies, 158 languages. Indexes a codebase into a persistent knowledge graph — average repo in milliseconds. 15 MCP tools for structural queries. Runs locally, code never leaves your machine.

**Install:**
```bash
curl -fsSL https://raw.githubusercontent.com/DeusData/codebase-memory-mcp/main/install.sh | bash
```
Installed to `~/.local/bin/codebase-memory-mcp`.

**Index a project:**
```
mcp({ tool: "index_repository", args: '{"repo_path": ".", "mode": "fast"}' })
```

**15 Tools:**

| Tool | What it does |
|------|-------------|
| `index_repository` | Index a repo (full/moderate/fast/cross-repo-intelligence modes) |
| `search_graph` | BM25 full-text search + semantic vector search for code |
| `query_graph` | Cypher queries — multi-hop patterns, complexity analysis |
| `trace_path` | Follow call chains, data flow, or cross-service HTTP via Route nodes |
| `get_code_snippet` | Read source code for a function/class/symbol |
| `get_graph_schema` | Show available node labels and edge types |
| `get_architecture` | High-level architecture: packages, clusters, routes, entry points |
| `search_code` | Grep + graph enrichment, ranked by structural importance |
| `list_projects` | List all indexed projects |
| `delete_project` | Remove a project from the graph |
| `index_status` | Check index freshness and stats |
| `detect_changes` | Find files changed since last index |
| `manage_adr` | Architecture Decision Records |
| `ingest_traces` | Import OpenTelemetry traces into the graph |

**MCP config** (`~/.pi/agent/mcp.json`):
```json
{
  "mcpServers": {
    "codebase-memory": {
      "command": "/home/sam/.local/bin/codebase-memory-mcp",
      "lifecycle": "lazy"
    }
  }
}
```

**Install on remote machines:**
```bash
ssh sam@192.168.20.51 "curl -fsSL https://raw.githubusercontent.com/DeusData/codebase-memory-mcp/main/install.sh | bash"
ssh sam@192.168.20.13 "curl -fsSL https://raw.githubusercontent.com/DeusData/codebase-memory-mcp/main/install.sh | bash"
```

**UI mode** (graph visualization at `localhost:9749`):
```bash
curl -fsSL .../install.sh | bash -s -- --ui
codebase-memory-mcp --ui=true --port=9749
```

Paper: [arXiv:2603.27277](https://arxiv.org/abs/2603.27277)

---

## engram + gentle-engram

engram v1.16.1 runs on nixos-desktop (.13) at `~/.local/bin/engram`. Systemd user service auto-starts. Binds `127.0.0.1:7437`, accessed via SSH tunnel: `ssh -fNL 7437:127.0.0.1:7437 192.168.20.13`.

**gentle-engram** connects via `ENGRAM_URL=http://127.0.0.1:7437`. Replaces memory-vault. Features: session capture, compaction recovery, private block redaction.

---

## MCP Servers

pi-mcp-adapter connects Pi to external services via the Model Context Protocol.

**Config files:** `~/.pi/agent/mcp.json` (pi global), `~/.config/mcp/mcp.json` (shared), `.mcp.json` (project)

```json
// ~/.pi/agent/mcp.json — pi MCP servers
{
  "mcpServers": {
    "codebase-memory": {
      "command": "/home/sam/.local/bin/codebase-memory-mcp",
      "lifecycle": "lazy"
    }
  }
}
```

Shared config at `~/.config/mcp/mcp.json`:
```json
{
  "mcpServers": {
    "filesystem": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-filesystem", "/home/sam"]
    }
  }
}
```

**Find MCP servers at:**
- [github.com/modelcontextprotocol/servers](https://github.com/modelcontextprotocol/servers)
- [smithery.ai](https://smithery.ai) — community registry

**Usage:**
- `/mcp` — interactive panel to manage servers
- `mcp({ search: "..." })` — search available tools
- `mcp({ tool: "tool_name", args: '{}' })` — call a tool
- Servers are lazy (connect on first use, disconnect after 10 min idle)

---

## Configuration Files

### Global (`~/.pi/agent/settings.json`)
- Nix store symlink — managed via `/etc/nixos/home/sam/home.nix`
- Contains: providers (opencode-go, openrouter, google), packages (pi-memctx, pi-prompt-template-model, Gitea)
- **Read-only** — cannot be modified by `pi install` or `/config-add`

### Project (`<project-dir>/.pi/settings.json`)
- Overrides global settings (arrays replace, not merge)
- Contains: `~/.agents` package (extensions + skills), Gitea package (tavily-search)
- Modified via `/config-add` / `/config-remove` commands

### Per-folder Memory (via pi-memctx)
- Memory stored in `<chat-folder>/.pi/memory-vault/packs/`
- Workspace map at `~/.pi/agent/memory-vault/00-system/workspace-map.json`
- Each chat folder has isolated memory (prevents sibling directory contamination)


### models.json (Provider Routing)

Path: `~/.pi/agent/models.json` (symlinked from `~/.agents/models.json` for Gitea). Injects OpenRouter provider routing for KV cache sharing. DeepSeek cache discount: 91.7% ($0.145/M vs $1.74/M input). Configured: deepseek, qwen, minimax, moonshotai. Mechanism: pi-core reads `model.compat.openRouterRouting` → injects `provider: { order: [...] }`.

### subagents.json

Path: `~/.pi/agent/subagents.json`. Configuration for pi-subagents agent types, default models, and providers.

---

## Useful Commands

| Command | What it does |
|---|---|
| `/config-setup` | One-shot: creates `.pi/`, `settings.json`, memory vault in current folder |
| `/config-add ext <name>` | Activate an extension from `~/.agents` |
| `/config-add skill <name>` | Activate a skill from `~/.agents` |
| `/config-show` | Show active extensions and skills |
| `/agents` | Interactive agent management (pi-subagents) |
| `/tasks` | Interactive task management (pi-tasks) |
| `/memctx-init` | Scan folder, build initial memory pack |
| `/memctx-status` | Show memory status |
| `/memctx-refresh` | Re-scan and enrich memory |
| `/filechanges` | Review changed files, diffs, accept/decline |
| `/filechanges-accept` | Accept all changes |
| `/filechanges-decline` | Revert all changes |
| `markitdown <file>` | Convert file to Markdown (PDF, Word, Excel, PPTX, images, HTML, etc.) |
| `markitdown-vision <file>` | Describe image using Qwen 2.5 VL 72B via OpenRouter |
| `Agent()` | Spawn subagent (pi-subagents) |
| `get_subagent_result()` | Retrieve results from background agent |
| `steer_subagent()` | Send mid-run steering message |
| `compress_for_agent()` | Compress large content via Headroom |


## Agent Roster (18)

| Agent | Model | Provider |
|-------|-------|----------|
| chat-search | google/gemini-2.5-flash:free | openrouter |
| code-analysis | deepseek-r1-distill-qwen-32b | opencode-go |
| code-ingest | google/gemini-2.5-flash:free | openrouter |
| coder-basic | deepseek/deepseek-chat | openrouter |
| coder-pro | deepseek/deepseek-v4-pro | openrouter |
| database | deepseek-r1-distill-qwen-32b | opencode-go |
| devops-basic | deepseek/deepseek-chat | openrouter |
| devops-pro | deepseek/deepseek-v4-pro | openrouter |
| document-writer | deepseek-r1-distill-qwen-32b | opencode-go |
| file-ops | qwen-coder-32b-instruct | opencode-go |
| home-automation | deepseek-r1-distill-qwen-32b | opencode-go |
| image-maker | black-forest-labs/flux-1-schnell | openrouter |
| iot-coder | qwen-coder-32b-instruct | opencode-go |
| iot-hardware | moonshotai/kimi-k2.6 | openrouter |
| obsidian | deepseek-r1-distill-qwen-14b | opencode-go |
| research | google/gemini-2.5-flash:free | openrouter |
| video-analyze | qwen/qwen-2.5-vl | openrouter |
| vscode-setup | qwen/qwen-3-coder-next | openrouter |

## Function Calls

```
Agent({ subagent_type, prompt, description, model?, thinking?, max_turns?, run_in_background?, resume?, isolated?, isolation?, inherit_context? })
get_subagent_result({ agent_id, wait?, verbose? })
steer_subagent({ agent_id, message })
compress_for_agent({ content })
```

---

## Skipped / Bookmarked

| Extension/Skill | Reason |
|---|---|
| **web-search** (amosblomqvist) | ❌ Redundant — Tavily does this |
| **subagents** (amosblomqvist) | ❌ Redundant — pi-subagents already installed |
| **bash-guard** (amosblomqvist) | ❌ Too aggressive — would interrupt flow |
| **google-image-search** (amosblomqvist) | ❌ Would need Google Search API + CSE setup |
| **pdf-reader** (amosblomqvist) | ⏳ Bookmarked — Python + pymupdf setup needed |
| **notify** (mitsuhiko) | ⏳ Minor QoL — desktop notifications on task complete |
| **audio/voice** | ⏳ Not practical | Pi TUI has no mic access or audio playback — fundamental platform limitation |

---

## Tasks

- [x] Rebuild NixOS to activate new packages ✅ 2026-06-11
- [x] Migrate to @tintinweb/pi-subagents with 18 agent types ✅ 2026-06-14
- [x] Deploy models.json with OpenRouter provider pinning (only: provider) ✅ 2026-06-14
- [x] Deploy engram + gentle-engram memory service on .13 ✅ 2026-06-13
- [x] Install pi-tasks (@tintinweb/pi-tasks) v0.7.0 ✅ 2026-06-13
- [x] Patch pi-subagents: 24h cleanup, disable clearCompleted ✅ 2026-06-14
- [x] Add memory: project to all 18 agent frontmats ✅ 2026-06-14
- [x] Remove custom subagent-registry skill (built-in /agents menu is sufficient) ✅ 2026-06-14
- [x] Update Pi Subagent.md and Pi Agent Extensions & Skills.md documentation ✅ 2026-06-14
- [x] Update pi-subagents to v0.10.3 ✅ 2026-06-14
- [x] Update pi-tasks to v0.7.0 ✅ 2026-06-13
- [ ] Verify video-extract works with Gemini
- [ ] Clean up workspace-map.json entries for any stale memory packs