Recipe Eval Skill

Context: Skill authoring (Phase A) followed by blind A/B evaluation (Phase B)

Mode: $ARGUMENTS

Orchestrator Definition

Core Identity: "I am not a worker. I am an orchestrator."

Execution Method:

• Skill generation/modification → performed by rashomon:skill-creator
• Skill quality grading → performed by rashomon:skill-reviewer
• Test task execution → performed by eval-executor.py script (via claude -p)
• Blind result comparison → performed by rashomon:skill-eval-reporter

Orchestrator invokes sub-agents via Agent tool and scripts via Bash, passes structured data between them.

First Action: Register all steps using TaskCreate before any execution. Phase A steps are defined in the mode-specific reference (create.md or update.md). Phase B steps are defined in eval.md. Update status using TaskUpdate upon each step completion.

Mode Detection

Determine mode from $ARGUMENTS:

| Mode | Criteria | |------|----------| | Creation | "create", new skill request, no existing skill referenced | | Update | "improve", "update", existing skill name or path mentioned | | Unspecified | $ARGUMENTS is empty or ambiguous | Ask user via AskUserQuestion: "Create a new skill or update an existing one?" |

Scope Boundaries

Phase A (Skill Authoring): Create or modify skill content through dialog. Ends with user-approved skill file. Phase B (Evaluation): Measure skill effectiveness through blind execution comparison. Does not modify skill content.

Responsibility Boundary: This skill completes with the combined evaluation report and ship/revise/reject recommendation.

Workflow

Phase A: Skill Authoring

Read the mode-specific reference and execute:

• Creation mode: Read [references/create.md](references/create.md) and follow its steps
• Update mode: Read [references/update.md](references/update.md) and follow its steps

Phase A ends with: user-approved skill content (new or modified).

Phase A → Phase B Handoff

Before starting Phase B, confirm these data are available in context. Phase B cannot proceed without them:

| Data | Source | Required | |------|--------|----------| | Skill name | Phase A dialog | Always | | Source skill directory | Phase A file write | Always | | User phrases | Phase A Round 3 (create) / Round 2 (update) | Always | | Trigger scenarios | Phase A Round 3 (create) / Round 1-2 (update) | Always | | Original SKILL.md content | Phase A Step 6 (update mode only) | Update mode |

If user phrases are missing, ask the user before proceeding: "What phrases does your team use when requesting work that this skill covers?"

Phase B: Evaluation

Read [references/eval.md](references/eval.md) and execute the evaluation protocol. Pass the handoff data above as context.

Phase B consists of:

1. Trigger check: Does the skill fire for its intended use case? (Step 1)
2. Trigger fail handling: Diagnose and revise if trigger fails (Step 2, conditional)
3. Execution effectiveness: Blind A/B comparison of output quality (Steps 3-7)

Final Output

Present combined results to user:

1. Phase A result: Skill quality grade (A/B/C from rashomon:skill-reviewer)
2. Phase B trigger: Discovered (yes/no), Invoked (yes/no)
3. Phase B execution: Blind comparison result (from rashomon:skill-eval-reporter)
4. Recommendation: ship / revise / reject

Error Handling

| Scenario | Behavior | |----------|----------| | User cancels during Phase A | Stop. No eval needed. | | Grade C after 2 iterations | Present content with issues. User decides: accept/revise/abort. | | One executor fails in Phase B | Continue with partial comparison. | | Both executors fail in Phase B | Report failure. Phase A result still valid. | | Worktree creation fails | Report git error. Phase A result still valid. |

Prerequisites

• Git repository (git 2.5+ for worktree support)
• claude CLI available in PATH
• Sufficient disk space for worktree copies

Completion Criteria

Phase A

• [ ] Skill knowledge collected through dialog
• [ ] rashomon:skill-creator returned valid output
• [ ] rashomon:skill-reviewer returned grade A or B
• [ ] User approved final content
• [ ] File written to target location

Phase B

• [ ] Trigger check executed and result presented
• [ ] Parallel execution completed in worktrees
• [ ] Blind comparison completed by rashomon:skill-eval-reporter
• [ ] Worktrees cleaned up
• [ ] Combined report presented with recommendation

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: shinpr
• Source: shinpr/rashomon
• License: MIT

Install and usage instructions live in the source repository linked above.