openspec-update-change

Revise a change's existing planning artifacts and keep them coherent. Never edit code.

Store selection: If the user names a store (a store is a standalone OpenSpec repo registered on this machine) or the work lives in one, run openspec store list --json to discover registered store ids, then pass --store <id> on the commands that read or write specs and changes (new change, status, instructions, list, show, validate, archive, doctor, context, schemas, view). Once selected, treat --store <id> as sticky for the rest of the workflow. Every unscoped example of those commands below is shorthand: before running it, append the flag. For example, run openspec status --change "<name>" --json --store "<id>", not the unscoped form shown below. Other commands do not take the flag. Hints printed by commands already carry the flag; keep it on follow-ups. Without a store, commands act on the nearest local openspec/ root.

Project check: These steps expect a project that already uses OpenSpec. Before the first step that writes anything (new change, archive, sync specs, or authoring an artifact file), confirm the project has a root: run openspec list --json (with --store <id> when a store is selected, since the store is then the root) and read root. A root object means the project is set up. "root": null means it is not - there is no openspec/ directory here, and a write such as openspec new change would create one as a side effect. The command also exits non-zero, which is that answer rather than a broken CLI, so read the JSON instead of retrying or working around it.

One "root": null is not about setup: when a status error message starts with Declared in or Invalid store declaration in and names this project's openspec/config.yaml (or config.yml), the project does use OpenSpec through a store it declares, which this machine cannot resolve (the store is not registered, or the store: line is malformed). Do not treat it as uninitialized and skip the branches below: stop before writing and show the user that error's message and fix.

Otherwise, with no root, what happens next depends on how this workflow was reached:

• Auto-selected: you chose this workflow yourself, without the user naming OpenSpec, naming this skill, or running its slash command. Stop using OpenSpec and answer the request normally, as you would with no OpenSpec installed. Do not ask them to set anything up and do not mention OpenSpec setup.
• Explicit OpenSpec request: the user named OpenSpec, named this skill, or ran its slash command. Stop before writing and ask how to proceed: set this project up (openspec init), target a store they already have (--store <id>), or continue without OpenSpec for this request. Wait for their answer.

In both branches, never create the root as a side effect: do not run openspec init until the user asks for it, do not hand-create openspec/ files, and do not let a command create it.

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.

This workflow revises artifacts that already exist; /openspec-continue-change is what creates the ones that do not.

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 sorted by most recently modified, and ask the user to select one

   When prompting, present the top 3-4 most recently modified changes as options, showing:

   • Change name
   • Schema (from schema field if present, otherwise "spec-driven")
   • Status (e.g., "0/5 tasks", "complete", "no tasks")
   • How recently it was modified (from lastModified field)

   Mark the most recently modified change as "(Recommended)" since it's likely what the user wants to update.

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

2. Get the change's artifacts

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

   Parse the JSON to understand current state. The response includes:

   • schemaName: The workflow schema being used (e.g., "spec-driven")
   • artifacts: Array of artifacts with their status ("done", "skipped", "ready", "blocked")
   • isPlanningComplete: Boolean indicating if all planning artifacts are complete. Older CLI versions expose the same value as isComplete.
   • planningHome, changeRoot, artifactPaths, and actionContext: path and scope context. Use these instead of assuming repo-local paths.

   The artifact ids and paths come from the active schema - do NOT assume them, and do NOT branch on hardcoded artifact names. Custom schemas must work unchanged.

   The files to edit are artifactPaths.<id>.existingOutputPaths - the concrete files that exist on disk, already glob-expanded for glob artifacts (e.g. specs/**/*.md). Do NOT write to resolvedOutputPath: for a glob artifact it is still the glob pattern, not a real file.

3. Understand the request

   • If the user asked for a specific revision ("the design now uses X"), that is the starting edit.
   • If they only said "update" / "make this coherent", treat it as a coherence review: read the existing artifacts and check them against each other for contradictions, gaps, and duplication.

4. Read and reconcile

   • Read the artifact(s) the request touches and the change's other existing artifacts.
   • Draft the requested edit in the conversation, not in files. Work out exactly what it changes; step 5 owns every write. Then check every other existing artifact against the drafted edit - in ANY direction: an edit to a later artifact may require revising an earlier one, not only the other way around. Build order is a useful reading order, not a constraint on which artifacts may be revised.
   • Note everything that is now inconsistent, missing, or contradictory.
   • Propose revisions only to files that already exist (existingOutputPaths). Do NOT create artifacts that don't exist yet, and do NOT invent new files under a glob artifact - note them and point the user to /openspec-continue-change to create them.
   • If the change is already coherent, say so and propose no revisions.

5. Confirm and apply, one artifact at a time

   • This step performs every artifact write in this workflow; no earlier step edits an artifact.
   • Show each proposed revision and why - including the requested edit drafted in step 4. Write only after the user confirms.
   • If the user rejects a revision, do not write it - leave that artifact unchanged.
   • When a substantial rewrite is needed, get that artifact's rules and template first:

     openspec instructions "<artifact-id>" --change "<name>" --json

6. Point to the next step (guidance only - NEVER act on it)

   • Artifacts still missing -> suggest /openspec-continue-change to create them.
   • Change already implemented (tasks checked off / already applied) -> the code may no longer match the revised plan; suggest /openspec-apply-change to carry the delta into code.
   • Everything done and implemented -> suggest /openspec-archive-change.

Output

After each invocation, show:

• Which artifacts were revised (and which proposed revisions were rejected)
• Anything deferred to /openspec-continue-change (not-yet-created artifacts or files)
• Where the change stands and the recommended next command

Guardrails

• Planning artifacts only - NEVER edit implementation code. If the revised plan implies code changes, stop and point to /openspec-apply-change.
• Use the artifact ids and paths reported by openspec status; never branch on hardcoded artifact names.
• Edit only the concrete files in existingOutputPaths; never write to a glob resolvedOutputPath.
• Do not advance the build frontier: no new artifacts, no new files under glob artifacts - that is /openspec-continue-change's job.
• Confirm every edit with the user before writing.
• If the request changes the change's intent rather than refining it, recommend starting fresh with /openspec-new-change (the "Update vs. Start Fresh" heuristic).