# Extension Guide V2

> Create Sindri V2 extensions for the Bash/Docker platform. Use when creating V2 extensions, understanding V2 extension.yaml structure, validating against V2 schema, or working with VisionFlow extensions. Covers mise, apt, binary, npm, script, hybrid install methods and the capabilities system.

- Skill: `pacphi/extension-guide-v2` (Agent Skill)
- Install (CLI): `npx skillmds@latest add pacphi/extension-guide-v2`
- Raw SKILL.md: https://api.skillmd.com/api/skills/pacphi/extension-guide-v2/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: DevOps & Infra
- Author: pacphi (https://skillmd.com/u/pacphi)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/pacphi/extension-guide-v2

---


# Sindri V2 Extension Development Guide

V2 extensions are YAML-driven, declarative configurations for the Bash/Docker-based Sindri platform.

## V2 Paths and Resources

| Resource | Path |
|----------|------|
| **Extensions Directory** | `v2/docker/lib/extensions/` |
| **Schema** | `v2/docker/lib/schemas/extension.schema.json` |
| **Registry** | `v2/docker/lib/registry.yaml` |
| **Categories** | `v2/docker/lib/categories.yaml` |
| **Profiles** | `v2/docker/lib/profiles.yaml` |
| **Extension Docs** | `docs/extensions/{NAME}.md` |
| **VisionFlow Docs** | `docs/extensions/vision-flow/VF-{NAME}.md` |

## V2 Categories

```yaml
# Valid V2 categories
- base          # Core system components
- agile         # Project management (Jira, Linear)
- language      # Programming runtimes
- dev-tools     # Development tools
- infrastructure # Cloud/container tools
- ai            # AI/ML tools
- database      # Database servers
- monitoring    # Observability tools
- mobile        # Mobile SDKs
- desktop       # GUI environments
- utilities     # General tools
```

## Quick Start Checklist

1. [ ] Create directory: `v2/docker/lib/extensions/{name}/`
2. [ ] Create `extension.yaml` with required sections
3. [ ] Add to `v2/docker/lib/registry.yaml`
4. [ ] Validate: `./v2/cli/extension-manager validate {name}`
5. [ ] Test: `./v2/cli/extension-manager install {name}`
6. [ ] Create docs: `docs/extensions/{NAME}.md`
7. [ ] Update catalog: `v2/docs/EXTENSIONS.md`

## Extension Directory Structure

```text
v2/docker/lib/extensions/{name}/
├── extension.yaml       # Required: Main definition
├── mise.toml            # Optional: mise configuration
├── scripts/             # Optional: Custom scripts
│   ├── install.sh
│   ├── uninstall.sh
│   └── validate.sh
└── templates/           # Optional: Config templates
    └── config.template
```

## Minimal Extension Template

```yaml
metadata:
  name: my-extension
  version: 1.0.0
  description: Brief description (10-200 chars)
  category: dev-tools
  dependencies: []

install:
  method: mise
  mise:
    configFile: mise.toml

validate:
  commands:
    - name: mytool
      versionFlag: --version
      expectedPattern: "v\\d+\\.\\d+\\.\\d+"
```

## Install Methods

### mise (Recommended for language tools)

```yaml
install:
  method: mise
  mise:
    configFile: mise.toml
    reshimAfterInstall: true
```

### apt (System packages)

```yaml
install:
  method: apt
  apt:
    repositories:
      - name: docker
        key: https://download.docker.com/linux/ubuntu/gpg
        url: https://download.docker.com/linux/ubuntu
        suite: jammy
        component: stable
    packages:
      - docker-ce
      - docker-ce-cli
```

### binary (Direct download)

```yaml
install:
  method: binary
  binary:
    url: https://github.com/org/repo/releases/download/v1.0.0/tool.tar.gz
    extract: tar.gz  # tar.gz, zip, or none
    destination: ~/.local/bin/tool
```

### npm (Node.js packages)

```yaml
install:
  method: npm
  npm:
    packages:
      - typescript
      - eslint@8.0.0
    global: true
```

### script (Custom installation)

```yaml
install:
  method: script
  script:
    path: scripts/install.sh
    timeout: 300
```

### hybrid (Multiple methods)

```yaml
install:
  method: hybrid
  hybrid:
    steps:
      - method: apt
        apt:
          packages: [build-essential]
      - method: script
        script:
          path: scripts/install.sh
```

## Capabilities (Optional - Advanced Extensions)

**Most extensions don't need capabilities.** Only use for extensions requiring:
- Project initialization (e.g., `claude-flow init`)
- Authentication validation
- Lifecycle hooks
- MCP server registration

```yaml
capabilities:
  # Project initialization
  project-init:
    enabled: true
    commands:
      - command: "mytool init --force"
        description: "Initialize mytool"
        requiresAuth: anthropic  # or: openai, github, none
        conditional: false
    state-markers:
      - path: ".mytool"
        type: directory
        description: "Config directory"
    validation:
      command: "mytool --version"
      expectedPattern: "^\\d+\\.\\d+"

  # Authentication
  auth:
    provider: anthropic
    required: false
    methods: [api-key, cli-auth]
    envVars: [ANTHROPIC_API_KEY]
    validator:
      command: "claude --version"
      expectedExitCode: 0
    features:
      - name: agent-spawn
        requiresApiKey: false
        description: "CLI-based features"

  # Lifecycle hooks
  hooks:
    pre-install:
      command: "echo 'Preparing...'"
      description: "Pre-install checks"
    post-install:
      command: "mytool --version"
      description: "Verify installation"

  # MCP server
  mcp:
    enabled: true
    server:
      command: "npx"
      args: ["-y", "@mytool/mcp", "start"]
      env:
        MYTOOL_MCP_MODE: "1"
    tools:
      - name: "mytool-action"
        description: "Perform action"
```

## Registry Entry

Add to `v2/docker/lib/registry.yaml`:

```yaml
extensions:
  my-extension:
    category: dev-tools
    description: Short description
    dependencies: [nodejs]
    protected: false
```

## Validation Commands

```bash
# Validate single extension
./v2/cli/extension-manager validate my-extension

# Validate all extensions
./v2/cli/extension-manager validate-all

# Check extension info
./v2/cli/extension-manager info my-extension

# Test installation
./v2/cli/extension-manager install my-extension

# Check status
./v2/cli/extension-manager status my-extension
```

## Common Patterns

### Language Runtime (No Capabilities)

```yaml
# v2/docker/lib/extensions/nodejs/extension.yaml
metadata:
  name: nodejs
  version: 1.0.0
  description: Node.js LTS via mise
  category: language

install:
  method: mise
  mise:
    configFile: mise.toml

validate:
  commands:
    - name: node
      expectedPattern: "v\\d+\\.\\d+\\.\\d+"
    - name: npm

bom:
  tools:
    - name: node
      version: dynamic
      source: mise
      type: runtime
      license: MIT
```

### AI Tool with Capabilities

```yaml
# Extensions like claude-flow-v2, agentic-qe, spec-kit
metadata:
  name: ai-tool
  version: 1.0.0
  description: AI-powered tool
  category: ai
  dependencies: [nodejs]

install:
  method: mise
  mise:
    configFile: mise.toml

capabilities:
  project-init:
    enabled: true
    commands:
      - command: "ai-tool init"
        description: "Initialize project"
        requiresAuth: anthropic
    state-markers:
      - path: ".ai-tool"
        type: directory

  auth:
    provider: anthropic
    methods: [api-key, cli-auth]

  mcp:
    enabled: true
    server:
      command: "npx"
      args: ["-y", "@ai-tool/mcp"]
    tools:
      - name: "ai-tool-action"
        description: "Perform AI action"
```

## V2-Specific Features

### VisionFlow Extensions

VisionFlow extensions use the `vf-` prefix and are only available in V2:

```text
v2/docker/lib/extensions/vf-{name}/
├── extension.yaml
└── ...
```

Document in: `docs/extensions/vision-flow/VF-{NAME}.md`

### Shell Aliases

V2 supports 158+ shell aliases defined in extensions. These are configured in the `configure.environment` section with `scope: bashrc`.

## Script Requirements

All scripts must:

```bash
#!/usr/bin/env bash
set -euo pipefail

echo "Installing..."
# Commands here
echo "Done"
```

## Post-Extension Documentation

After creating an extension, update:

1. **Registry**: `v2/docker/lib/registry.yaml`
2. **Extension Doc**: `docs/extensions/{NAME}.md`
3. **Catalog**: `v2/docs/EXTENSIONS.md`
4. **Profiles** (if applicable): `v2/docker/lib/profiles.yaml`

## Troubleshooting

| Issue | Solution |
|-------|----------|
| Schema validation fails | Check YAML syntax, verify required fields |
| Dependencies not found | Add to registry.yaml first |
| Install times out | Increase timeout in script section |
| Validation fails | Check regex escaping in expectedPattern |