Extension system for Spec Kit - add new functionality without bloating the core framework.
Spec Kit provides two catalog files with different purposes:
- Purpose: Default upstream catalog of extensions used by the Spec Kit CLI
- Default State: Empty by design in the upstream project - you or your organization populate a fork/copy with extensions you trust
- Location (upstream):
extensions/catalog.jsonin the GitHub-hosted spec-kit repo - CLI Default: The
specify extensioncommands use the upstream catalog URL by default, unless overridden - Org Catalog: Point
SPECKIT_CATALOG_URLat your organization's fork or hosted catalog JSON to use it instead of the upstream default - Customization: Copy entries from the community catalog into your org catalog, or add your own extensions directly
Example override:
# Override the default upstream catalog with your organization's catalog
export SPECKIT_CATALOG_URL="https://your-org.com/spec-kit/catalog.json"
specify extension search # Now uses your organization's catalog instead of the upstream default- Purpose: Browse available community-contributed extensions
- Status: Active - contains extensions submitted by the community
- Location:
extensions/catalog.community.json - Usage: Reference catalog for discovering available extensions
- Submission: Open to community contributions via Pull Request
How It Works:
You control which extensions your team can discover and install:
Populate your catalog.json with approved extensions:
- Discover extensions from various sources:
- Browse
catalog.community.jsonfor community extensions - Find private/internal extensions in your organization's repos
- Discover extensions from trusted third parties
- Browse
- Review extensions and choose which ones you want to make available
- Add those extension entries to your own
catalog.json - Team members can now discover and install them:
specify extension searchshows your curated catalogspecify extension add <name>installs from your catalog
Benefits: Full control over available extensions, team consistency, organizational approval workflow
Example: Copy an entry from catalog.community.json to your catalog.json, then your team can discover and install it by name.
Skip catalog curation - team members install directly using URLs:
specify extension add --from https://github.com/org/spec-kit-ext/archive/refs/tags/v1.0.0.zipBenefits: Quick for one-off testing or private extensions
Tradeoff: Extensions installed this way won't appear in specify extension search for other team members unless you also add them to your catalog.json.
The following community-contributed extensions are available in catalog.community.json:
| Extension | Purpose | URL |
|---|---|---|
| Azure DevOps Integration | Sync user stories and tasks to Azure DevOps work items using OAuth authentication | spec-kit-azure-devops |
| Cleanup Extension | Post-implementation quality gate that reviews changes, fixes small issues (scout rule), creates tasks for medium issues, and generates analysis for large issues | spec-kit-cleanup |
| Fleet Orchestrator | Orchestrate a full feature lifecycle with human-in-the-loop gates across all SpecKit phases | spec-kit-fleet |
| Jira Integration | Create Jira Epics, Stories, and Issues from spec-kit specifications and task breakdowns with configurable hierarchy and custom field support | spec-kit-jira |
| Ralph Loop | Autonomous implementation loop using AI agent CLI | spec-kit-ralph |
| Retrospective Extension | Post-implementation retrospective with spec adherence scoring, drift analysis, and human-gated spec updates | spec-kit-retrospective |
| Review Extension | Post-implementation comprehensive code review with specialized agents for code quality, comments, tests, error handling, type design, and simplification | spec-kit-review |
| Spec Sync | Detect and resolve drift between specs and implementation. AI-assisted resolution with human approval | spec-kit-sync |
| Understanding | Automated requirements quality analysis — 31 deterministic metrics against IEEE/ISO standards with experimental energy-based ambiguity detection | understanding |
| V-Model Extension Pack | Enforces V-Model paired generation of development specs and test specs with full traceability | spec-kit-v-model |
| Verify Extension | Post-implementation quality gate that validates implemented code against specification artifacts | spec-kit-verify |
To add your extension to the community catalog:
- Prepare your extension following the Extension Development Guide
- Create a GitHub release for your extension
- Submit a Pull Request that:
- Adds your extension to
extensions/catalog.community.json - Updates this README with your extension in the Available Extensions table
- Adds your extension to
- Wait for review - maintainers will review and merge if criteria are met
See the Extension Publishing Guide for detailed step-by-step instructions.
Before submitting, ensure:
- ✅ Valid
extension.ymlmanifest - ✅ Complete README with installation and usage instructions
- ✅ LICENSE file included
- ✅ GitHub release created with semantic version (e.g., v1.0.0)
- ✅ Extension tested on a real project
- ✅ All commands working as documented
Once extensions are available (either in your catalog or via direct URL), install them:
# From your curated catalog (by name)
specify extension search # See what's in your catalog
specify extension add <extension-name> # Install by name
# Direct from URL (bypasses catalog)
specify extension add --from https://github.com/<org>/<repo>/archive/refs/tags/<version>.zip
# List installed extensions
specify extension listFor more information, see the Extension User Guide.