msd-core/gsd-core/workflows/mvp-phase.md

Guide the user through MVP-mode planning for a phase. Prompts for an "As a / I want to / So that" user story, runs SPIDR splitting check on the story, writes the result to ROADMAP.md, and delegates to `/gsd plan-phase` (which auto-detects MVP via the roadmap mode field shipped in PRD Phase 1).

<required_reading> @/.claude/gsd-core/references/user-story-template.md @/.claude/gsd-core/references/spidr-splitting.md @~/.claude/gsd-core/references/planner-mvp-mode.md </required_reading>

<runtime_note> Copilot (VS Code): Use vscode_askquestions wherever this workflow calls AskUserQuestion. They are equivalent.

TEXT_MODE fallback: Set TEXT_MODE=true if --text is present in $ARGUMENTS OR text_mode from init JSON is true. When TEXT_MODE is active, replace every AskUserQuestion call with a plain-text numbered list and ask the user to type their choice number. </runtime_note>

1. Parse and validate phase argument

Extract the phase number from $ARGUMENTS (integer or decimal like 2.1). Optional flag: --force (allow operating on in_progress / completed phases).

If no argument:

ERROR: Phase number required
Usage: /gsd mvp-phase <phase-number>
Example: /gsd mvp-phase 1
Example: /gsd mvp-phase 2.1

Exit.

Normalize per @~/.claude/gsd-core/references/phase-argument-parsing.md (zero-pad integer phases to two digits).

2. Validate phase exists and check status

_GSD_SHIM_NAME="gsd-tools.cjs"; _GSD_RUNTIME_ROOT="${RUNTIME_DIR:-$(git rev-parse --show-toplevel 2>/dev/null || pwd)}"; GSD_TOOLS="${_GSD_RUNTIME_ROOT}/gsd-core/bin/${_GSD_SHIM_NAME}"; if [ -f "$GSD_TOOLS" ]; then gsd_run() { node "$GSD_TOOLS" "$@"; }; elif [ -f "${_GSD_RUNTIME_ROOT}/.claude/gsd-core/bin/${_GSD_SHIM_NAME}" ]; then GSD_TOOLS="${_GSD_RUNTIME_ROOT}/.claude/gsd-core/bin/${_GSD_SHIM_NAME}"; gsd_run() { node "$GSD_TOOLS" "$@"; }; elif command -v gsd-tools >/dev/null 2>&1; then GSD_TOOLS="$(command -v gsd-tools)"; gsd_run() { "$GSD_TOOLS" "$@"; }; elif [ -f "$HOME/.claude/gsd-core/bin/${_GSD_SHIM_NAME}" ]; then GSD_TOOLS="$HOME/.claude/gsd-core/bin/${_GSD_SHIM_NAME}"; gsd_run() { node "$GSD_TOOLS" "$@"; }; else echo "ERROR: gsd-tools.cjs not found at $GSD_TOOLS and gsd-tools is not on PATH. Run: npx -y @opengsd/gsd-core@latest --claude --local" >&2; exit 1; fi
PHASE_INFO=$(gsd_run query roadmap.get-phase "${PHASE}")
PHASE_FOUND=$(echo "$PHASE_INFO" | jq -r '.found')
PHASE_NAME=$(echo "$PHASE_INFO" | jq -r '.phase_name')
PHASE_GOAL=$(echo "$PHASE_INFO" | jq -r '.goal')
PHASE_MODE=$(echo "$PHASE_INFO" | jq -r '.mode // ""')
PHASE_COMPLETE=$(echo "$PHASE_INFO" | jq -r '.roadmap_complete // false')

ANALYZE=$(gsd_run query roadmap.analyze)
if [[ "$ANALYZE" == @file:* ]]; then ANALYZE=$(cat "${ANALYZE#@file:}"); fi
DISK_STATUS=$(echo "$ANALYZE" | jq -r --arg p "$PHASE" '.phases[] | select((.phase_number|tostring)==$p) | .disk_status' | head -1)
if [[ "$DISK_STATUS" == "complete" || "$PHASE_COMPLETE" == "true" ]]; then
  STATUS="completed"
elif [[ "$DISK_STATUS" == "planned" || "$DISK_STATUS" == "partial" ]]; then
  STATUS="in_progress"
else
  STATUS="not_started"
fi

If PHASE_FOUND is false: error and exit. Suggest /gsd add-phase or /gsd insert-phase to create the phase first.

Status guard. If the phase is in_progress (has plans but not complete) or completed, refuse unless --force is in $ARGUMENTS:

ERROR: Phase ${PHASE} is currently ${STATUS}.
Converting an active or completed phase to MVP mode mid-flight will
invalidate any existing plans and summaries.

To proceed anyway: /gsd mvp-phase ${PHASE} --force

Already-MVP guard. If PHASE_MODE is already mvp, surface this and ask whether to re-prompt the user story or abort:

"Phase ${PHASE} is already in MVP mode with goal: «${PHASE_GOAL}». Re-run user-story prompts and SPIDR check?"

Use AskUserQuestion with options [Re-prompt / Abort]. On Abort, exit cleanly. On Re-prompt, proceed.

3. User story prompts

Run three sequential AskUserQuestion calls. Each is free-text. After all three, assemble into the canonical sentence per @~/.claude/gsd-core/references/user-story-template.md:

Prompt 1 — As a:

"As a [user role]?" (Examples: "new user", "admin", "signed-in customer", "API consumer")

Prompt 2 — I want to:

"I want to [capability]?" (Examples: "register and log in", "upload a CSV", "see my dashboard")

Prompt 3 — So that:

"So that [outcome]?" (Examples: "I can access my account", "I can bulk-import contacts", "I can see at a glance what needs attention")

Assemble:

USER_STORY="As a ${ROLE}, I want to ${CAPABILITY}, so that ${OUTCOME}."

If any of the three answers is empty or whitespace-only, error and re-prompt that single field. Do NOT proceed with a partial story.

Validate via the centralized User Story validator. The verb owns the canonical regex /^As a .+, I want to .+, so that .+\.$/ and surfaces per-error guidance:

USER_STORY_RESULT=$(gsd_run query user-story.validate --story "$USER_STORY")
if [ "$(echo "$USER_STORY_RESULT" | jq -r '.valid')" != "true" ]; then
  echo "$USER_STORY_RESULT" | jq -r '.errors[]' >&2
  # Re-prompt the offending field(s) per surfaced errors, then re-run validation.
  # Do not abort the workflow on first invalid draft.
  RE_PROMPT_USER_STORY=true
fi

This guarantees the goal stored in ROADMAP.md will satisfy the same guard the verifier applies later. If RE_PROMPT_USER_STORY=true, re-run only the offending prompt field(s), rebuild USER_STORY, and validate again before continuing.

4. SPIDR splitting check

Run the SPIDR rules from @~/.claude/gsd-core/references/spidr-splitting.md. Briefly:

Trigger evaluation. Check the assembled USER_STORY against the four size signals from the reference (compound capabilities, multi-actor, length > 120 chars, vague capability). If none fire, skip SPIDR entirely — go to step 5.

If SPIDR triggers.

a) Restate the story to the user:

"Your story: «${USER_STORY}»

This story has [signal description, e.g., 'two compound capabilities joined by and']. Splitting it into multiple phases will produce a cleaner Walking Skeleton and reduce the risk of mid-phase scope creep.

Want to walk through SPIDR splitting?"

Use AskUserQuestion with options [Yes, walk through SPIDR / No, proceed with the story as-is].

If "No": skip SPIDR, go to step 5.

If "Yes": continue to (b).

b) Ask which SPIDR axis fits best:

"Which axis best fits how to split this story?"

Use AskUserQuestion with the five options from spidr-splitting.md (Spike / Paths / Interfaces / Data / Rules). Each option includes its targeted question as the description so the user can pick by understanding what each axis means.

c) Walk through the chosen axis with one targeted question (not all five). For example, if the user picked "Paths":

"Does this feature have a happy path and one or more error/edge paths?"

Free-text response. Workflow parses to identify the split.

d) Produce a split proposal. Example:

"Proposed split (Paths axis):

• Phase ${PHASE} (this one): Happy path — ${HAPPY_STORY}
• Phase ${PHASE+1} (new): Edge case — ${EDGE_STORY}

Accept this split?"

Use AskUserQuestion [Accept / Modify / Reject].

• Accept: USER_STORY becomes the first split's story (${HAPPY_STORY} in the example). Surface the remaining splits as a list of /gsd add-phase invocations the user can run after this command completes — do NOT auto-create the new phases (preserve user control over numbering).
• Modify: re-prompt the splits one more time, then accept or reject.
• Reject: revert USER_STORY to the original, proceed without splitting.

5. Update ROADMAP.md

Read ROADMAP.md. Find the section for Phase ${PHASE}. Apply two edits:

Edit 1 — Update Goal line.

Find: **Goal:** ${OLD_GOAL_TEXT} Replace with: **Goal:** ${USER_STORY}

Edit 2 — Insert Mode line.

If **Mode:** already exists in the section (replacing or re-running), update it to **Mode:** mvp. If **Mode:** does not exist, insert **Mode:** mvp on the line immediately after **Goal:**.

Show the user a unified diff (lines being changed) and ask:

"Apply these changes to ROADMAP.md?"

Use AskUserQuestion [Apply / Cancel]. On Cancel, exit without writing.

On Apply, write the updated ROADMAP.md atomically (read-edit-write).

6. Verify the write

NEW_MODE=$(gsd_run query roadmap.get-phase "${PHASE}" --pick mode)
NEW_GOAL=$(gsd_run query roadmap.get-phase "${PHASE}" --pick goal)

Assert:

• NEW_MODE equals mvp
• NEW_GOAL equals the assembled user story

If either assertion fails, surface the discrepancy to the user and exit. Do not proceed to plan-phase delegation with a half-applied write.

7. Delegate to /gsd plan-phase

Invoke /gsd plan-phase ${PHASE} (no flags). Phase 1's MVP_MODE resolution chain (CLI flag → roadmap mode → config → false) will detect the new **Mode:** mvp line and run plan-phase in vertical-slice mode automatically.

The Walking Skeleton gate (also from Phase 1) will fire automatically if ${PHASE} == "01" and there are zero prior phase summaries.

8. Surface deferred phase splits (if any)

If SPIDR produced a split in step 4, append a final user-facing message:

"SPIDR split deferred phases.

Your original story was split. The first slice is now planned via plan-phase. To create the remaining slice(s) as new phases, run:

• /gsd add-phase — for the next slice: «${SPLIT_2_STORY}»
• /gsd add-phase — for the next slice: «${SPLIT_3_STORY}»

Each will be added to the end of the current milestone. You can then run /gsd mvp-phase <new-phase-number> on each to plan them as MVP slices."

9. Exit

Workflow ends. The phase is now in MVP mode with a planned PLAN.md, optionally with deferred follow-up phases surfaced for the user.