Execute the implementation planning workflow using the plan template to generate design artifacts.
$ARGUMENTS
You MUST consider the user input before proceeding (if not empty).
Check for extension hooks (before planning):
Check if .specify/extensions.yml exists in the project root.
If it exists, read it and look for entries under the hooks.before_plan key
If the YAML cannot be parsed or is invalid, skip hook checking silently and continue normally
Filter out hooks where enabled is explicitly false. Treat hooks without an enabled field as enabled by default.
For each remaining hook, do not attempt to interpret or evaluate hook condition expressions:
condition field, or it is null/empty, treat the hook as executablecondition, skip the hook and leave condition evaluation to the HookExecutor implementationFor each executable hook, output the following based on its optional flag:
Optional hook (optional: true):
## Extension Hooks
**Optional Pre-Hook**: {extension}
Command: `/{command}`
Description: {description}
Prompt: {prompt}
To execute: `/{command}`
Mandatory hook (optional: false):
## Extension Hooks
**Automatic Pre-Hook**: {extension}
Executing: `/{command}`
EXECUTE_COMMAND: {command}
Wait for the result of the hook command before proceeding to the Outline.
If no hooks are registered or .specify/extensions.yml does not exist, skip silently
Setup: Run .specify/scripts/bash/setup-plan.sh --json from repo root and parse JSON for FEATURE_SPEC, IMPL_PLAN, SPECS_DIR, BRANCH. For single quotes in args like "I'm Groot", use escape syntax: e.g 'I'''m Groot' (or double-quote if possible: "I'm Groot").
Load context: Read FEATURE_SPEC and .specify/memory/constitution.md. Load IMPL_PLAN template (already copied).
Execute plan workflow: Follow the structure in IMPL_PLAN template to:
Stop and report: Command ends after Phase 2 planning. Report branch, IMPL_PLAN path, and generated artifacts.
Check for extension hooks: After reporting, check if .specify/extensions.yml exists in the project root.
If it exists, read it and look for entries under the hooks.after_plan key
If the YAML cannot be parsed or is invalid, skip hook checking silently and continue normally
Filter out hooks where enabled is explicitly false. Treat hooks without an enabled field as enabled by default.
For each remaining hook, do not attempt to interpret or evaluate hook condition expressions:
condition field, or it is null/empty, treat the hook as executablecondition, skip the hook and leave condition evaluation to the HookExecutor implementationFor each executable hook, output the following based on its optional flag:
Optional hook (optional: true):
## Extension Hooks
**Optional Hook**: {extension}
Command: `/{command}`
Description: {description}
Prompt: {prompt}
To execute: `/{command}`
Mandatory hook (optional: false):
## Extension Hooks
**Automatic Hook**: {extension}
Executing: `/{command}`
EXECUTE_COMMAND: {command}
If no hooks are registered or .specify/extensions.yml does not exist, skip silently
Extract unknowns from Technical Context above:
Generate and dispatch research agents:
For each unknown in Technical Context:
Task: "Research {unknown} for {feature context}"
For each technology choice:
Task: "Find best practices for {tech} in {domain}"
Consolidate findings in research.md using format:
Output: research.md with all NEEDS CLARIFICATION resolved
Prerequisites: research.md complete
Extract entities from feature spec → data-model.md:
Define interface contracts (if project has external interfaces) → /contracts/:
Agent context update:
.specify/scripts/bash/update-agent-context.sh claudeOutput: data-model.md, /contracts/*, quickstart.md, agent-specific file