Sync delta specs from a change to main specs. Use when the user wants to update main specs with changes from a delta spec, without archiving the change.
Sync delta specs from a change to main specs.
This is an agent-driven operation - you will read delta specs and directly edit main specs to apply the changes. This allows intelligent merging (e.g., adding a scenario without copying the entire requirement).
Input: Optionally specify a change name. If omitted, check if it can be inferred from conversation context. If vague or ambiguous you MUST prompt for available changes.
Steps
If no change name provided, prompt for selection
Run openspec list --json to get available changes. Use the AskUserQuestion tool to let the user select.
Show changes that have delta specs (under specs/ directory).
IMPORTANT: Do NOT guess or auto-select a change. Always let the user choose.
Find delta specs
Look for delta spec files in openspec/changes/<name>/specs/*/spec.md.
Each delta spec file contains sections like:
## ADDED Requirements - New requirements to add## MODIFIED Requirements - Changes to existing requirements## REMOVED Requirements - Requirements to remove## RENAMED Requirements - Requirements to rename (FROM:/TO: format)If no delta specs found, inform user and stop.
For each delta spec, apply changes to main specs
For each capability with a delta spec at openspec/changes/<name>/specs/<capability>/spec.md:
a. Read the delta spec to understand the intended changes
b. Read the main spec at openspec/specs/<capability>/spec.md (may not exist yet)
c. Apply changes intelligently:
ADDED Requirements:
MODIFIED Requirements:
REMOVED Requirements:
RENAMED Requirements:
d. Create new main spec if capability doesn't exist yet:
openspec/specs/<capability>/spec.mdShow summary
After applying all changes, summarize:
Delta Spec Format Reference
## ADDED Requirements
### Requirement: New Feature
The system SHALL do something new.
#### Scenario: Basic case
- **WHEN** user does X
- **THEN** system does Y
## MODIFIED Requirements
### Requirement: Existing Feature
#### Scenario: New scenario to add
- **WHEN** user does A
- **THEN** system does B
## REMOVED Requirements
### Requirement: Deprecated Feature
## RENAMED Requirements
- FROM: `### Requirement: Old Name`
- TO: `### Requirement: New Name`
Key Principle: Intelligent Merging
Unlike programmatic merging, you can apply partial updates:
Output On Success
## Specs Synced: <change-name>
Updated main specs:
**<capability-1>**:
- Added requirement: "New Feature"
- Modified requirement: "Existing Feature" (added 1 scenario)
**<capability-2>**:
- Created new spec file
- Added requirement: "Another Feature"
Main specs are now updated. The change remains active - archive when implementation is complete.
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