rpi-implement

name	rpi-implement
description	Use when you have a plan from /rpi-plan and want to execute it. Dispatches a fresh subagent per task with two-stage review (spec compliance → code quality), then runs a baked-in end-of-implementation audit that re-runs success criteria, checks the diff against the plan, and dispatches /quick-review across the SHA range.

Execute a /rpi-plan plan by dispatching a fresh subagent per task with two-stage review after each, then running a baked-in audit pass at the end.

RPI principle: Research documents what is. Plan decides what should change. Implement performs the change and verifies it.

Core principle: Fresh subagent per task + two-stage review per task + end-of-impl audit = high quality, traceable execution.

Announce at start: "Starting /rpi-implement."

Setup

1. Run "$SKILL_BASE_DIR/setup.sh" "$ARGUMENTS" and parse stdout for REPO, TOPIC_SLUG, ARTIFACT_DIR. $SKILL_BASE_DIR is the "Base directory for this skill" path shown at the top of this prompt.
   • If the script exits 2, AskUserQuestion for a slug.

Pre-flight Validation

• <ARTIFACT_DIR>/plan.md exists → if not: "Plan not found at <path>. Run /rpi-plan <slug> first." Stop.
• Assume implementation happens on the current feature branch. Final audit/review should cover the branch's changes against its merge base with the parent branch.

Tooling

Use the agent's native task tools (TaskCreate, TaskUpdate, TaskList). Track per-task dependencies via TaskUpdate's dependency field.

Model Selection

Use the following models for Task tool dispatches:

• implementer, spec reviewer: model: "sonnet"
• code quality reviewer, session quick-review: model: "opus".

Plan Structure Expectations

When dispatching the implementer subagent, include the full task text plus the relevant excerpts from Research Context (typically ### Files in scope and ### Patterns to follow). Do NOT have subagents read the whole plan file.

The Process

digraph process {
    rankdir=TB;

    "Read plan.md, extract all tasks + Research Context, create TaskList" [shape=box];
    "More tasks remain?" [shape=diamond];

    subgraph cluster_per_task {
        label="Per Task";
        "Dispatch implementer subagent" [shape=box];
        "Implementer asks questions?" [shape=diamond];
        "Answer, provide context" [shape=box];
        "Implementer codes, tests, commits, self-reviews" [shape=box];
        "Dispatch spec reviewer" [shape=box];
        "Spec compliant?" [shape=diamond];
        "Fix spec gaps" [shape=box];
        "Dispatch code-quality reviewer" [shape=box];
        "Code quality approved?" [shape=diamond];
        "Fix quality issues" [shape=box];
        "Mark task complete in TaskList + plan.md Task Completion table" [shape=box];
    }

    subgraph cluster_audit {
        label="End-of-Impl Audit";
        "Run all phase success-criteria commands" [shape=box];
        "Audit [x] checkboxes vs branch diff" [shape=box];
        "Dispatch /quick-review on branch diff" [shape=box];
        "Aggregate audit findings" [shape=box];
        "Critical/Significant findings?" [shape=diamond];
        "AskUserQuestion: which to fix?" [shape=box];
        "Apply selected fixes" [shape=box];
    }

    "Completion" [shape=box style=filled fillcolor=lightgreen];

    "Read plan.md, extract all tasks + Research Context, create TaskList" -> "Dispatch implementer subagent";
    "Dispatch implementer subagent" -> "Implementer asks questions?";
    "Implementer asks questions?" -> "Answer, provide context" [label="yes"];
    "Answer, provide context" -> "Dispatch implementer subagent";
    "Implementer asks questions?" -> "Implementer codes, tests, commits, self-reviews" [label="no"];
    "Implementer codes, tests, commits, self-reviews" -> "Dispatch spec reviewer";
    "Dispatch spec reviewer" -> "Spec compliant?";
    "Spec compliant?" -> "Fix spec gaps" [label="no"];
    "Fix spec gaps" -> "Dispatch spec reviewer" [label="re-review"];
    "Spec compliant?" -> "Dispatch code-quality reviewer" [label="yes"];
    "Dispatch code-quality reviewer" -> "Code quality approved?";
    "Code quality approved?" -> "Fix quality issues" [label="no"];
    "Fix quality issues" -> "Dispatch code-quality reviewer" [label="re-review"];
    "Code quality approved?" -> "Mark task complete in TaskList + plan.md Task Completion table" [label="yes"];
    "Mark task complete in TaskList + plan.md Task Completion table" -> "More tasks remain?";
    "More tasks remain?" -> "Dispatch implementer subagent" [label="yes"];
    "More tasks remain?" -> "Run all phase success-criteria commands" [label="no"];

    "Run all phase success-criteria commands" -> "Audit [x] checkboxes vs branch diff";
    "Audit [x] checkboxes vs branch diff" -> "Dispatch /quick-review on branch diff";
    "Dispatch /quick-review on branch diff" -> "Aggregate audit findings";
    "Aggregate audit findings" -> "Critical/Significant findings?";
    "Critical/Significant findings?" -> "AskUserQuestion: which to fix?" [label="yes"];
    "AskUserQuestion: which to fix?" -> "Apply selected fixes";
    "Apply selected fixes" -> "Completion";
    "Critical/Significant findings?" -> "Completion" [label="no"];
}

Prompt Templates

Subagent dispatches read their prompts from siblings in this directory:

• ./implementer-prompt.md
• ./spec-reviewer-prompt.md
• ./code-quality-reviewer-prompt.md

Per-Task Execution

For each task in the plan, in order:

1. Dispatch implementer subagent (./implementer-prompt.md, model: "sonnet"). Pass: full task text + relevant excerpts from ## Research Context (typically ### Files in scope and ### Patterns to follow).
2. If implementer asks questions: answer, then re-dispatch.
3. Dispatch spec reviewer (./spec-reviewer-prompt.md, model: "sonnet"). Pass: task requirements + implementer's report.
4. If spec reviewer rejects: fix the spec gaps; re-dispatch spec reviewer. Loop until approved.
5. Dispatch code-quality reviewer (./code-quality-reviewer-prompt.md, model: "sonnet"). Pass: implementer's report + the relevant task commit/diff range.
6. If code-quality reviewer rejects: fix the quality issues; re-dispatch code-quality reviewer. Loop until approved.
7. Mark task complete: update both TaskUpdate and the Task Completion table in plan.md (status [x], fill the short SHA in Committed). If the implementer deviated from the plan, append an entry to the Deviation Log in plan.md.

Resume

If invoked on a plan with some tasks already [x]:

1. Read the Task Completion table; collect IDs with status [x] (done) or [-] (skipped).
2. Skip those. Begin per-task execution at the first task with status [ ], [~], or [!].
3. For [~] (in progress): check git status. If clean, restart the task. If dirty, AskUserQuestion: discard / proceed from dirty state.
4. For [!] (blocked): read the Deviation Log; AskUserQuestion whether the blocker is resolved before re-dispatching.
5. For resume, continue using the current feature branch as the unit of work; do not try to infer an implementation baseline from task commits.

End-of-Implementation Audit

After all tasks are marked complete, read ./audit-checklist.md and run that audit before declaring implementation done. Review the current feature branch's changes against its merge base with the parent branch.

Completion

Report:

• Tasks completed (count) and Phase Progress / Task Completion tables fully filled.
• Audit summary: success criteria results, plan-vs-diff verdict, /quick-review verdict, any fixes applied.
• Branch/diff range reviewed for traceability.
• Plan file path: <ARTIFACT_DIR>/plan.md.

Red Flags

Never:

• Skip the per-task spec compliance OR code quality review — both must pass before a task closes.
• Skip the end-of-impl audit because "the per-task reviews already caught everything" — the audit catches cross-task issues per-task reviews can't (regressions, scope creep, missed phase criteria).
• Dispatch multiple implementer subagents in parallel (commit conflicts).
• Make subagents read the full plan file — pass full task text + relevant Research Context excerpts only.
• Let implementer self-review replace external review — both are needed.

If a subagent asks questions: answer before letting them proceed.

If a reviewer finds issues: fix them and have the reviewer re-review; repeat until approved.

If an audit finding requires a fix: dispatch a fresh fix subagent rather than editing manually (avoids context pollution).

If success criteria fail at audit time: treat as Critical — fix before completion. A plan whose own success criteria don't pass after implementation is not done.