skill-z3-implementation

---
name: skill-z3-implementation
description: Implement Z3 constraints. Invoke for Z3-language implementation tasks.
allowed-tools: Agent, Bash, Edit, Read, Write
---

# Z3 Implementation Skill

Thin wrapper that delegates Z3 implementation to `z3-implementation-agent` subagent.

## Trigger Conditions

This skill activates when:
- Task type is "z3"
- /implement command targets a Z3 task
- Plan exists and task is ready for implementation

## Execution Flow

### Stage 1: Input Validation
Validate task_number exists and language is "z3".

### Stage 2: Preflight Status Update
Update status to "implementing" BEFORE invoking subagent.

### Stage 3: Prepare Delegation Context
Include task_context, plan_path, metadata_file_path.

### Stage 4: Invoke Subagent
Use Agent tool with subagent_type: "z3-implementation-agent".

### 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 status value "implemented".

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 from `specs/{N}_{SLUG}/.return-meta.json`.

### Stage 6: Update Task Status (Postflight)
Update state.json and TODO.md based on result.

### Stage 7: Link Artifacts
Add artifact to state.json with summary. Update TODO.md per `@.claude/context/patterns/artifact-linking-todo.md` with `field_name=**Summary**`, `next_field=**Description**`.

### Stage 8: Git Commit
Commit changes with session ID.

### Stage 9: Return Brief Summary

## MUST NOT (Postflight Boundary)

After the agent returns, this skill MUST NOT:

1. **Edit Z3 files** - All constraint work is done by agent
2. **Run z3 solver** - Verification is done by agent
3. **Analyze or grep source** - Analysis is agent work
4. **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

Brief text summary (NOT JSON).