Apply spec modifications systematically. Use to apply review feedback, bulk modifications, or interactive spec updates with safety checks, validation, and rollback support.
Inherits all available tools
Additional assets for this skill
This skill inherits all available tools. When active, it can use any tool Claude has access to.
reference.mdUse Skill(foundry:sdd-modify) to:
Do NOT use for:
sdd-update)sdd-plan)sdd-next)Safe Systematic Changes: Modifications are applied with automatic backup, preview (dry-run), validation, and rollback capabilities. Never apply changes without previewing first. The spec file is the source of truth, and all changes flow through MCP tools that handle validation automatically.
This skill operates entirely through the Foundry MCP server (foundry-mcp). Tools use the router+action pattern: mcp__plugin_foundry_foundry-mcp__<router> with action="<action>".
| Router | Actions | Purpose |
|---|---|---|
spec | apply-plan, validate, validate-fix, get, get-hierarchy, list | Modifications and validation |
review | parse-feedback | Convert review markdown to modifications JSON |
authoring | update-frontmatter, task-add, task-remove | Add/remove nodes |
task | update-metadata | Update task metadata fields |
verification | add | Add verification results |
journal | add | Document modifications |
Critical Rules:
Read() on spec JSON filescat, grep, jq) on specsThis skill is part of the Spec-Driven Development workflow:
sdd-plan --> sdd-plan-review --> sdd-modify (this skill) --> sdd-next --> Implementation --> sdd-update
^
sdd-fidelity-review ------+
Use after sdd-plan-review or sdd-fidelity-review to apply suggested changes.
| Operation | sdd-modify | sdd-update |
|---|---|---|
| Update task descriptions | Yes | No |
| Add/remove tasks | Yes | No |
| Add verification steps | Yes | No |
| Apply review feedback | Yes | No |
| Mark task completed | No | Yes |
| Update task status | No | Yes |
| Add journal entries | Both | Yes |
| Move spec between folders | No | Yes |
Key Distinction:
For detailed workflow steps with examples, see
reference.md#workflow-details
Parse the input to identify:
mcp__plugin_foundry_foundry-mcp__review action="parse-feedback" spec_id="{spec-id}" review_path="{path}"
This converts markdown review findings into structured modification JSON.
mcp__plugin_foundry_foundry-mcp__spec action="apply-plan" spec_id="{spec-id}" modifications_file="{path}" dry_run=true
Review the preview output: tasks to update, verification steps to add, metadata changes, impact summary.
After confirming preview looks correct:
mcp__plugin_foundry_foundry-mcp__spec action="apply-plan" spec_id="{spec-id}" modifications_file="{path}"
The tool automatically creates backup, applies modifications, validates result, and rolls back if validation fails.
Confirm spec is valid:
mcp__plugin_foundry_foundry-mcp__spec action="validate" spec_id="{spec-id}"
If validation issues found, apply auto-fixes:
mcp__plugin_foundry_foundry-mcp__spec action="validate-fix" spec_id="{spec-id}" auto_fix=true
| Operation | Purpose |
|---|---|
update_task | Modify task title, description, file_path, category |
add_verification | Add verification step to task |
update_metadata | Update task metadata (hours, priority, etc.) |
batch_update | Apply same change to multiple nodes |
add_node | Add new task/subtask/verify node |
remove_node | Remove node (optionally cascading) |
For detailed operation formats and examples, see
reference.md#operation-formats
specs/.backups/{spec-id}-{timestamp}.json)For rollback and recovery procedures, see
reference.md#error-handling
Return a structured summary:
## Modification Summary
**Spec:** {spec-id}
**Source:** {review report or modifications file}
### Changes Applied
- Updated X task descriptions
- Added Y verification steps
- Modified Z metadata fields
### Backup Location
`specs/.backups/{spec-id}-{timestamp}.json`
### Validation Status
{PASSED | FAILED with details}
### Next Steps
- {Contextual recommendations}
For comprehensive documentation including:
See reference.md