Spec Kit Canon

What Is Canon?

Canon is a body of work, rules, or descriptions considered authoritative and official. For a codebase, it is the agreed description of how the system is supposed to work.

Spec Kit Canon represents that source of truth as a structured set of Markdown documents. The canon can cover business rules, domains, architecture, terminology, and workflows, organized into nested areas with _toc.md indexes.

Why Spec Kit Canon?

Spec Kit Canon adds canon-driven workflows to Spec Kit.

Code and specifications naturally drift during feature work, bug fixes, and low-ceremony vibecoding. Spec Kit Canon provides structured spec-first and code-first workflows for detecting that drift, reviewing the intended truth, and bringing the canon and implementation back into alignment.

Packages

The product is distributed as two version-locked packages that are installed together:

• canon: the primary extension, its speckit.canon.* commands, scripts, templates, configuration, and complete product documentation
• canon-core: the required companion preset that adapts core speckit.* commands to the canon-driven workflow

canon-core is not a standalone product. Install it at the same version as the canon extension.

Workflow Quick Reference

All workflows assume both canon and canon-core are installed.

Workflow	Use it when	Command order
Standard spec-first	Requirements should lead implementation and canon should participate throughout the normal Spec Kit lifecycle.	1. /speckit.specify 2. /speckit.clarify 3. /speckit.checklist 4. /speckit.plan 5. /speckit.tasks 6. /speckit.analyze (optional) 7. /speckit.implement 8. Polish the implementation 9. Run the standard drift recovery workflow below
Standard drift recovery	Implementation has diverged from an existing specification and the differences require review.	1. /speckit.canon.drift-reverse 2. /speckit.canon.drift-detect 3. /speckit.canon.drift-resolve 4. /speckit.canon.drift-implement (when alignment tasks exist) 5. /speckit.canon.drift-reconcile 6. /speckit.canon.drift-analyze (optional) 7. /speckit.canon.drift-canonize
Vibecoding code-first	You want to start implementation with minimal ceremony and synchronize the canon afterward.	1. /speckit.canon.vibecode-specify "<intent>" 2. Implement the change 3. Run the vibecoding drift workflow below
Vibecoding drift recovery	A vibecoding implementation is ready to be captured in canon.	1. /speckit.canon.vibecode-drift-reverse 2. /speckit.canon.vibecode-drift-detect 3. /speckit.canon.vibecode-drift-reconcile 4. /speckit.canon.vibecode-drift-analyze (optional) 5. /speckit.canon.vibecode-drift-canonize

For end-to-end execution, use orchestration commands: /speckit.canon.drift for standard drift, /speckit.canon.vibecode-drift for vibecoding drift, or /speckit.canon.vibecode-drift-express for the shortest vibecoding path for simple changes.

Documentation

• Extension documentation
• Development documentation