skill-lean-implementation

# Lean Implementation Skill Thin wrapper that delegates Lean 4 proof implementation to `lean-implementation-agent` subagent. **IMPORTANT**: This skill implements the skill-internal postflight pattern. After the subagent returns, this skill handles all postflight operations (status update, artifact linking, git commit) before returning. ## Trigger Conditions This skill activates when: - Task type is "lean4" or "lean" (either accepted) - /implement command targets a Lean task - Plan exists and task is ready for implementation --- ## Execution Flow ### Stage 1: Input Validation Validate required inputs: - `task_number` - Must be provided and exist in state.json - Task status must allow implementation (planned, implementing, partial) - Task language must be "lean" ```bash # Lookup task task_data=$(jq -r --argjson num "$task_number" \ '.active_projects[] | select(.project_number == $num)' \ specs/state.json) # Validate exists if [ -z "$task_data" ]; then return error "Task $task_number not found" fi # Extract fields task_type=$(echo "$task_data" | jq -r '.task_type // "general"') status=$(echo "$task_data" | jq -r '.status') project_name=$(echo "$task_data" | jq -r '.project_name') # Validate task_type (accept both "lean" and "lean4") if [ "$task_type" != "lean" ] && [ "$task_type" != "lean4" ]; then return error "Task $task_number is not a Lean task" fi ``` --- ### Stage 2: Preflight Status Update Update task status to "implementing" BEFORE invoking subagent. ```bash bash .claude/scripts/update-task-status.sh preflight "$task_number" implement "$session_id" ``` --- ### Stage 3: Prepare Delegation Context Prepare delegation context for the subagent: ```json { "session_id": "sess_{timestamp}_{random}", "delegation_depth": 1, "delegation_path": ["orchestrator", "implement", "skill-lean-implementation"], "timeout": 7200, "task_context": { "task_number": N, "task_name": "{project_name}", "description": "{description}", "task_type": "lean" }, "plan_path": "specs/{N}_{SLUG}/plans/MM_{short-slug}.md", "metadata_file_path": "specs/{N}_{SLUG}/.return-meta.json" } ``` --- ### Stage 4: Invoke Subagent **CRITICAL**: You MUST use the **Agent** tool to spawn the subagent. **Required Tool Invocation**: ``` Tool: Agent (NOT Skill, NOT Plan) Parameters: - subagent_type: "lean-implementation-agent" - prompt: [Include task_context, delegation_context, plan_path, metadata_file_path] - description: "Execute Lean implementation for task {N}" ``` **DO NOT** use `Skill(lean-implementation-agent)` - this will FAIL. The subagent will: - Load implementation context files (MCP tools guide, tactic patterns) - Parse plan and find resume point - Execute phases sequentially using lean-lsp MCP tools - Verify proofs with `lean_goal` and `lake build` (detached, via the build guard — see `context/project/lean4/operations/long-builds.md`) - Create implementation summary - Write metadata to `specs/{N}_{SLUG}/.return-meta.json` - Return a brief text summary (NOT JSON) --- ### Stage 4b: Self-Execution Fallback **CRITICAL**: If you performed the work above WITHOUT using the Agent tool (i.e., you read files, wrote artifacts, or updated metadata directly instead of spawning a subagent), you MUST write a `.return-meta.json` file now before proceeding to postflight. Use the schema from `return-metadata-file.md` with the appropriate status value for this operation. If you DID use the Agent tool, skip this stage -- the subagent already wrote the metadata. --- ## Postflight (ALWAYS EXECUTE) The following stages MUST execute after work is complete, whether the work was done by a subagent or inline (Stage 4b). Do NOT skip these stages for any reason. ### Stage 5: Parse Subagent Return Read the metadata file: ```bash metadata_file="specs/${padded_num}_${project_name}/.return-meta.json" if [ -f "$metadata_file" ] && jq empty "$metadata_file" 2>/dev/null; then status=$(jq -r '.status' "$metadata_file") artifact_path=$(jq -r '.artifacts[0].path // ""' "$metadata_file") phases_completed=$(jq -r '.metadata.phases_completed // 0' "$metadata_file") phases_total=$(jq -r '.metadata.phases_total // 0' "$metadata_file") # Read verification results (agent is responsible for verification) verification_passed=$(jq -r '.verification.verification_passed // false' "$metadata_file") else echo "Error: Invalid or missing metadata file" status="failed" verification_passed="false" fi ``` **Note**: The agent performs all verification (sorry check, axiom check, lake build — detached and guarded, see `context/project/lean4/operations/long-builds.md`) and records results in metadata. This skill reads those results - it does NOT re-verify. --- ### Stage 6b: Plan Compliance Check (Read from Metadata) **This stage only runs if status from metadata is "implemented".** Read the agent-reported compliance result from metadata (agent ran the grep check in Final Verification Stage; SKILL reads the result — MUST NOT re-run grep per postflight-tool-restrictions.md): ```bash if [ "$status" = "implemented" ]; then compliance_check=$(jq -r '.metadata.compliance_check // "skipped"' "$metadata_file" 2>/dev/null) case "$compliance_check" in "failed") echo "Stage 6b: Plan compliance check FAILED (agent reported)" echo " See agent output for missing deliverables or integrity violations" status="partial" ;; "passed") echo "Stage 6b: Plan compliance check PASSED" ;; "skipped"|*) echo "Stage 6b: INFO — compliance_check absent or skipped; proceeding" ;; esac fi ``` **Architecture note**: The `.claude/` skill MUST NOT run grep or shell analysis in postflight (see postflight-tool-restrictions.md). The lean-implementation-agent runs the check during Final Verification Stage and records results in metadata. This stage reads that result only. --- ### Stage 6: Update Task Status (Postflight) **If status is "implemented" AND verification_passed is true**: ```bash bash .claude/scripts/update-task-status.sh postflight "$task_number" implement "$session_id" --phase-check=warn ``` Then add completion_data to state.json (not covered by centralized script): ```bash # Extract completion_data fields from metadata (if present) completion_summary=$(jq -r '.completion_data.completion_summary // ""' "$metadata_file") roadmap_items=$(jq -c '.completion_data.roadmap_items // []' "$metadata_file") # Add completion_summary if present if [ -n "$completion_summary" ]; then bash .claude/scripts/state-write.sh \ '(.active_projects[] | select(.project_number == $num)).completion_summary = $summary' \ --session-id "$session_id" \ --argjson num "$task_number" \ --arg summary "$completion_summary" fi # Add roadmap_items if present (for non-meta tasks only) if [ "$task_type" != "meta" ] && [ "$roadmap_items" != "[]" ] && [ -n "$roadmap_items" ]; then bash .claude/scripts/state-write.sh \ '(.active_projects[] | select(.project_number == $num)).roadmap_items = $items' \ --session-id "$session_id" \ --argjson num "$task_number" \ --argjson items "$roadmap_items" fi ``` **If status is "partial"**: Keep status as "implementing" but update resume point. TODO.md stays as `[IMPLEMENTING]`. --- ### Stage 7: Link Artifacts Add summary artifact to state.json. Update TODO.md per `@.claude/context/patterns/artifact-linking-todo.md` with `field_name=**Summary**`, `next_field=**Description**`. ```bash if [ -n "$summary_artifact_path" ]; then bash .claude/scripts/state-write.sh \ '(.active_projects[] | select(.project_number == $num)).artifacts += [{"path": $path, "type": "summary", "summary": $summary}]' \ --session-id "$session_id" \ --argjson num "$task_number" \ --arg path "$summary_artifact_path" \ --arg summary "$summary_artifact_summary" fi ``` --- ### Stage 8: Git Commit Commit changes with session ID: ```bash git add \ "Theories/" \ "specs/${padded_num}_${project_name}/summaries/" \ "specs/${padded_num}_${project_name}/plans/" \ "specs/TODO.md" \ "specs/state.json" git commit -m "task ${task_number}: complete implementation Session: ${session_id} ``` --- ### Stage 9: Return Brief Summary Return a brief text summary (NOT JSON). Example: ``` Lean implementation completed for task {N}: - All {phases_total} phases executed, all proofs verified - Lake build: Success - Key theorems: {theorem names} - Created summary at specs/{N}_{SLUG}/summaries/MM_{short-slug}-summary.md - Status updated to [COMPLETED] - Changes committed ``` --- ## Error Handling ### Input Validation Errors Return immediately with error message if task not found, wrong language, or status invalid. ### Metadata File Missing If subagent didn't write metadata file: 1. Keep status as "implementing" 2. Report error to user ### Git Commit Failure Non-blocking: Log failure but continue with success response. ### Subagent Timeout Return partial status if subagent times out (default 7200s). Keep status as "implementing" for resume. --- ## MUST NOT (Postflight Boundary) After the agent returns, this skill MUST NOT: 1. **Edit source files** - All Lean proof work is done by agent 2. **Run lake build** - Build verification is done by agent (the agent's build is detached and guarded — see `context/project/lean4/operations/long-builds.md`) 3. **Use MCP tools** - lean-lsp tools are for agent use only 4. **Grep for sorries** - Debt analysis is agent work 5. **Write summary/reports** - Artifact creation is agent work > **PROHIBITION**: If the subagent returned partial or failed status, the lead skill MUST NOT attempt to continue, complete, or "fill in" the subagent's work. Report the partial/failed status and let the user re-run `/implement` to resume. The postflight phase is LIMITED TO: - Reading agent metadata file - Updating state.json via jq - Updating TODO.md status marker via Edit - Linking artifacts in state.json - Git commit - Cleanup of temp/marker files Reference: @.claude/context/standards/postflight-tool-restrictions.md --- ## Return Format This skill returns a **brief text summary** (NOT JSON). The JSON metadata is written to the file and processed internally.