openspec-apply-change

name	openspec-apply-change
description	Implement tasks from an OpenSpec change. Use when the user wants to start implementing, continue implementation, or work through tasks.
license	MIT
compatibility	Requires openspec CLI.
metadata	{"author":"openspec","version":"1.0","generatedBy":"1.2.0"}

Implement tasks from an OpenSpec change.

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.

Question-asking discipline (read first)

Apply phase has a single consolidated preflight round at the start, then near-silence during the implementation loop. The user round-trip budget for apply is one batched question round upfront, not one micro-question per task.

• Preflight (step 5b below) — bundle every genuine remaining blocker into one AskUserQuestion call. Scope: empty highly-desirable .dev.env fields needed by tasks in this session's plan, plus design.md → ## Open Questions items whose dependent task is in this session's plan. Nothing else.
• Implementation loop (step 6 below) — no mid-loop questions except: a new fact surfaces from the live state that conflicts with a locked artifact decision (metadata missing, platform-version mismatch with CompatibilityMode, БСП subsystem absent, typical-form structure blocks the planned approach); or the user explicitly re-opens a decision. Routine ambiguity in a task ("what name for this private helper?", "function or procedure?", "what level of logging?") is never a legitimate mid-loop pause — it is a propose-phase defect that the propose-phase clarification gate should have caught. Make a reasonable, codebase-consistent choice and record it via remember or memory.md Captured-during-work.
• The full rule lives in content/rules/sdd-integrations.md → Apply-phase clarification discipline. Load it on any non-trivial apply session.

Steps

1. Select the change

   If a name is provided, use it. Otherwise:

   • Infer from conversation context if the user mentioned a change
   • Auto-select if only one active change exists
   • If ambiguous, run openspec list --json to get available changes and use the AskUserQuestion tool to let the user select

   Always announce: "Using change: " and how to override (e.g., /opsx:apply <other>).

2. Check status to understand the schema

   openspec status --change "<name>" --json
   

   Parse the JSON to understand:

   • schemaName: The workflow being used (e.g., "spec-driven")
   • Which artifact contains the tasks (typically "tasks" for spec-driven, check status for others)

3. Get apply instructions

   openspec instructions apply --change "<name>" --json
   

   This returns:

   • Context file paths (varies by schema - could be proposal/specs/design/tasks or spec/tests/implementation/docs)
   • Progress (total, complete, remaining)
   • Task list with status
   • Dynamic instruction based on current state

   Handle states:

   • If state: "blocked" (missing artifacts): show message, suggest using openspec-continue-change
   • If state: "all_done": congratulate, suggest archive
   • Otherwise: proceed to implementation

4. Read context files

   Read the files listed in contextFiles from the apply instructions output. The files depend on the schema being used:

   • spec-driven: proposal, specs, design, tasks
   • Other schemas: follow the contextFiles from CLI output

5. Show current progress and emit the opening message (preflight round)

   a. Display:

   • Schema being used
   • Progress: "N/M tasks complete"
   • Remaining tasks overview
   • Dynamic instruction from CLI

   b. Emit the apply-phase opening message following the template in content/rules/sdd-integrations.md → Apply-phase opening template:

   Using change: <name>.
   
   ## Locked from artifacts (proceeding without re-asking)
   - <decision>: <one-line value> — `<file>:<section>`
   - ...
   
   ## Plan for this session
   - <ordered list of task ids that will be executed in this run>
   
   ## Genuine blockers (preflight — single consolidated round)
   - <empty .dev.env field needed by a task in this session's plan> — required by tasks <ids>
   - <design.md Open Question whose dependent task is in this session's plan> — CONFUSION block (quote question + list options with consequences + the agent's recommendation + "→ Which one to pick?")
   - ...
   

   c. Preflight scope filter — for each candidate question, include in ## Genuine blockers only if it passes all of:

   • Not answered in proposal.md / design.md / delta specs/ / tasks.md (those decisions are locked — quote them in ## Locked from artifacts instead).
   • Not an advisory field (PREFIX, COMPANY, DEVELOPER) or a defaulted field (INFOBASE_KIND, EXTENSION_NAME, EXPORT_PATH, NEW_OBJECTS_IN, IBCMD_CONFIG).
   • In scope of the current session's plan — required by a task that this apply run will actually reach.

   d. If ## Genuine blockers is empty after the filter — omit the block entirely and proceed straight to step 6. An empty block is not a question.

   e. If ## Genuine blockers is non-empty — submit the consolidated AskUserQuestion round (one call, all questions in it). On the user's response, apply the answers to the artifacts: write resolved Open Questions into design.md → ## Architecture decisions and strike them from ## Open Questions; persist .dev.env values. Then enter the implementation loop. The preflight round is the only apply-time question surface — no further AskUserQuestion calls during step 6 except for the narrow critical exceptions below.

6. Implement tasks (loop until done or blocked)

   For each pending task:

   • Show which task is being worked on
   • Make the code changes required
   • Keep changes minimal and focused
   • Mark task complete in the tasks file: - [ ] → - [x]
   • Continue to next task

   Mid-loop pause is reserved for true live-state surprises only. Pause if and only if:

   • New fact from live state conflicts with a locked artifact decision — metadata object missing from this configuration, platform-version mismatch with CompatibilityMode, БСП subsystem absent, typical-form structure blocks the planned approach, an attribute / tabular-section actual type contradicts what design.md assumed. Raise a CONFUSION block per AGENTS.md → 1. with the new fact, the locked artifact it contradicts, and the resolution options. This is the only routine reason to pause mid-loop.
   • User-explicit re-open — the user asks to revisit a previously locked decision.
   • Error or hard blocker — a tool / build / validator returns a result that genuinely blocks progress (not a style warning, not a routine BSL defect — fix those and continue).
   • User interrupts — obvious.

   Forbidden mid-loop pauses (each is an apply-phase defect of the same severity as skipping syntaxcheck):

   • "Task is unclear" — propose-phase defect. Make a reasonable, codebase-consistent choice and record it via remember (project memory) or memory.md Captured-during-work. Do not interrupt the user.
   • "What name for this private helper?" / "function or procedure?" / "what logging level?" / "should I add a comment here?" — same.
   • "Should I pause now to re-confirm decision X from design.md?" — never. Confirmation is not a question.
   • "Should I pause for an empty .dev.env field that the user already declined in preflight?" — never. The dependent block is marked deferred-to-user in tasks.md; proceed with everything else.

7. On completion or pause, show status

   Display:

   • Tasks completed this session
   • Overall progress: "N/M tasks complete"
   • If all done: suggest archive
   • If paused: explain why and wait for guidance

Output During Implementation

## Implementing: <change-name> (schema: <schema-name>)

Working on task 3/7: <task description>
[...implementation happening...]
✓ Task complete

Working on task 4/7: <task description>
[...implementation happening...]
✓ Task complete

Output On Completion

## Implementation Complete

**Change:** <change-name>
**Schema:** <schema-name>
**Progress:** 7/7 tasks complete ✓

### Completed This Session
- [x] Task 1
- [x] Task 2
...

All tasks complete! Ready to archive this change.

Output On Pause (Issue Encountered)

## Implementation Paused

**Change:** <change-name>
**Schema:** <schema-name>
**Progress:** 4/7 tasks complete

### Issue Encountered
<description of the issue>

**Options:**
1. <option 1>
2. <option 2>
3. Other approach

What would you like to do?

Guardrails

• Keep going through tasks until done or blocked
• Always read context files before starting (from the apply instructions output)
• Bundle every legitimate question into the single preflight round at step 5b — no mid-loop questions except for the narrow critical exceptions in step 6. "If task is ambiguous, pause and ask" is not the apply rule for this project — the rule is in content/rules/sdd-integrations.md → Apply-phase clarification discipline. Routine ambiguity is a propose-phase defect; make a reasonable, codebase-consistent choice and record it via remember or memory.md Captured-during-work.
• If a live-state fact conflicts with a locked artifact decision, raise a CONFUSION block and pause; this is the only routine mid-loop pause.
• Keep code changes minimal and scoped to each task
• Update task checkbox immediately after completing each task
• Pause on hard errors / blockers (failing validator with a substantive defect, missing metadata, deadlock), never on routine style warnings or naming choices
• Use contextFiles from CLI output, don't assume specific file names

Fluid Workflow Integration

This skill supports the "actions on a change" model:

• Can be invoked anytime: Before all artifacts are done (if tasks exist), after partial implementation, interleaved with other actions
• Allows artifact updates: If implementation reveals design issues, suggest updating artifacts - not phase-locked, work fluidly