1---2name: openspec-apply-change3description: Implement tasks from an OpenSpec change. Use when the user wants to start implementing, continue implementation, or work through tasks.4license: MIT5compatibility: Requires openspec CLI.6metadata:7 author: openspec8 version: "1.0"9 generatedBy: "1.4.1"10---1112Implement tasks from an OpenSpec change.1314**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.1516**Steps**17181. **Select the change**1920 If a name is provided, use it. Otherwise:21 - Infer from conversation context if the user mentioned a change22 - Auto-select if only one active change exists23 - If ambiguous, run `openspec list --json` to get available changes and use the **AskUserQuestion tool** to let the user select2425 Always announce: "Using change: <name>" and how to override (e.g., `/opsx:apply <other>`).26272. **Check status to understand the schema**28 ```bash29 openspec status --change "<name>" --json30 ```31 Parse the JSON to understand:32 - `schemaName`: The workflow being used (e.g., "spec-driven")33 - `planningHome`, `changeRoot`, and `actionContext`: planning scope and edit constraints34 - Which artifact contains the tasks (typically "tasks" for spec-driven, check status for others)35363. **Get apply instructions**3738 ```bash39 openspec instructions apply --change "<name>" --json40 ```4142 This returns:43 - `contextFiles`: artifact ID -> array of concrete file paths (varies by schema - could be proposal/specs/design/tasks or spec/tests/implementation/docs)44 - Progress (total, complete, remaining)45 - Task list with status46 - Dynamic instruction based on current state4748 **Handle states:**49 - If `state: "blocked"` (missing artifacts): show message, suggest using openspec-continue-change50 - If `state: "all_done"`: congratulate, suggest archive51 - Otherwise: proceed to implementation5253 **Workspace guard:** If status JSON reports `actionContext.mode: "workspace-planning"` and `allowedEditRoots` is empty, explain that full workspace apply is not supported in this slice. Treat linked repos and folders as read-only context, ask the user to select an affected area through an explicit implementation workflow, and STOP before editing files.54554. **Read context files**5657 Read every file path listed under `contextFiles` from the apply instructions output.58 The files depend on the schema being used:59 - **spec-driven**: proposal, specs, design, tasks60 - Other schemas: follow the contextFiles from CLI output61625. **Show current progress**6364 Display:65 - Schema being used66 - Progress: "N/M tasks complete"67 - Remaining tasks overview68 - Dynamic instruction from CLI69706. **Implement tasks (loop until done or blocked)**7172 For each pending task:73 - Show which task is being worked on74 - Make the code changes required75 - Keep changes minimal and focused76 - Mark task complete in the tasks file: `- [ ]` → `- [x]`77 - Continue to next task7879 **Pause if:**80 - Task is unclear → ask for clarification81 - Implementation reveals a design issue → suggest updating artifacts82 - Error or blocker encountered → report and wait for guidance83 - User interrupts84857. **On completion or pause, show status**8687 Display:88 - Tasks completed this session89 - Overall progress: "N/M tasks complete"90 - If all done: suggest archive91 - If paused: explain why and wait for guidance9293**Output During Implementation**9495```96## Implementing: <change-name> (schema: <schema-name>)9798Working on task 3/7: <task description>99[...implementation happening...]100✓ Task complete101102Working on task 4/7: <task description>103[...implementation happening...]104✓ Task complete105```106107**Output On Completion**108109```110## Implementation Complete111112**Change:** <change-name>113**Schema:** <schema-name>114**Progress:** 7/7 tasks complete ✓115116### Completed This Session117- [x] Task 1118- [x] Task 2119...120121All tasks complete! Ready to archive this change.122```123124**Output On Pause (Issue Encountered)**125126```127## Implementation Paused128129**Change:** <change-name>130**Schema:** <schema-name>131**Progress:** 4/7 tasks complete132133### Issue Encountered134<description of the issue>135136**Options:**1371. <option 1>1382. <option 2>1393. Other approach140141What would you like to do?142```143144**Guardrails**145- Keep going through tasks until done or blocked146- Always read context files before starting (from the apply instructions output)147- If task is ambiguous, pause and ask before implementing148- If implementation reveals issues, pause and suggest artifact updates149- Keep code changes minimal and scoped to each task150- Update task checkbox immediately after completing each task151- Pause on errors, blockers, or unclear requirements - don't guess152- Use contextFiles from CLI output, don't assume specific file names153154**Fluid Workflow Integration**155156This skill supports the "actions on a change" model:157158- **Can be invoked anytime**: Before all artifacts are done (if tasks exist), after partial implementation, interleaved with other actions159- **Allows artifact updates**: If implementation reveals design issues, suggest updating artifacts - not phase-locked, work fluidly