st-plan

name	st-plan
description	Plan phase of the workflow chain. Uses Opus to design an implementation strategy. Use when the user wants to create a detailed plan before executing changes.

Plan Phase

Design the implementation strategy for the user's task.

Instructions

steop state set-phase plan --mode plan

Launch the architect agent (steop:architect, Opus, read-only tools).

Note: When invoked from st-flow with FLOW MODE, produce the blueprint and return it immediately without asking for approval. The instructions below describe standalone behavior.

Provide the agent with all available context from prior research (if any) plus the user's task description.

Prefer the simpler of two equivalent designs. If the Research Summary flagged an area that YAGNI would skip, skip it unless the Task Brief's Success criteria require it. Don't design for hypothetical future requirements not stated in the brief.

The planning agent should produce:

• Goal — clear statement of what will be achieved
• Steps — ordered list of implementation steps, each with:
  • File(s) to modify or create
  • What changes to make and why
  • Any risks or edge cases
• Architecture decisions — trade-offs considered and choices made. For each decision, state an Alternative considered (simpler option the decision rejected) in one line. Format: <chosen> chosen over <alternative> because <reason>.
• Testing strategy — how to verify the implementation works. Reference the Task Brief's Success criteria — don't restate them; point to them. Add plan-specific verification steps using step → verify: format where helpful.

After the agent completes, present the plan to the user and ask for approval or adjustments before proceeding to execution.