Guide · Agent skill
How to use the A-Evolve Agent Improvement skill (a-evolve)
Updated · written with AI from the project's own documentation and checked against our catalogue data
The a-evolve skill gives an AI agent a structured way to learn from its own repeated failures. You point it at run logs, error traces or experiment outputs, and it walks through a five-step loop (Solve, Observe, Evolve, Gate, Reload) to propose targeted fixes. This guide explains what the skill does, how to install it, how to trigger it with plain requests, and what to check before you trust its output.
Quick start
- 1Download the ZIP. Download the a-evolve ZIP from the directory page. It contains the SKILL.md file.
- 2Unzip into a skills folder. Unzip the folder into ~/.claude/skills/ for personal use, or into your project's .claude/skills/ folder.
- 3Or upload in the Claude apps. In the Claude apps, go to Settings → Capabilities → Skills and upload the skill.
- 4Gather your run evidence. Collect run logs, error traces, pass/fail results and metric values for the agent you want to improve.
- 5Ask for a diagnosis. Use a natural request such as "diagnose the failures in this run log and tell me how to fix them".
- 6Review the proposed mutations. Check each skill, prompt patch or knowledge entry against your own judgment before applying it.
- 7Record the change. Add the accepted change to your evolution log and re-run the failed tasks to see whether it helped.
What the a-evolve skill makes the agent do
A skill is a folder containing a SKILL.md file with instructions that an agent reads when a request matches the skill's description. The a-evolve skill is instructions only: it has no external dependencies and no harness changes. It tells the agent how to analyse agent runs and write proposed artifacts.
The skill follows the Solve → Observe → Evolve → Gate → Reload methodology from the A-Evolve project. The agent collects evidence, diagnoses failures by category, proposes mutations, checks them against a gate, and then presents accepted changes for you to place in your project.
- Solve: gather run logs, error traces, pass/fail results and metric values.
- Observe: group failures by category, root cause, frequency and severity.
- Evolve: propose a new SKILL.md, a short system prompt patch, a JSON knowledge entry, or nothing.
- Gate: check specificity, testability, blast radius and consistency with existing guidance.
- Reload: present accepted changes with suggested file locations and keep a running evolution log.
Install the a-evolve skill
Download the ZIP containing SKILL.md from the directory page and unzip it. For a personal install, place the folder in ~/.claude/skills/. For a single project, place it in that project's .claude/skills/ folder.
If you use the Claude apps, you can instead upload the skill under Settings → Capabilities → Skills.
- Personal install: unzip into ~/.claude/skills/
- Project install: unzip into your project's .claude/skills/
- Claude apps: Settings → Capabilities → Skills, then upload
Trigger the skill with natural requests
The skill's description lists trigger phrases, so you usually do not need a special command. Describe the problem in plain language. Phrases that match the description include "evolve", "self-improve", "diagnose failures", "generate skills from errors", "what went wrong and how to fix it", or any mention of A-Evolve.
Give the agent the evidence it needs. Pointing it at a log file or results folder works better than a vague complaint.
- "Diagnose the failures in this run log and tell me what went wrong and how to fix it."
- "Evolve the system prompt based on the errors in these experiment outputs."
- "Generate skills from the recurring errors in last night's agent batch."
- "Self-improve my agent using these pass/fail results."
What the output looks like
The skill asks the agent to write observations as a structured list with an ID, error category, affected tasks, root cause, frequency and severity. Proposed mutations follow from those observations. A generated skill should target one specific failure category, be under 100 lines, and include a "when to apply" trigger.
The skill also sets limits: no more than three skills per evolution cycle, surgical prompt patches rather than rewrites, and no tool code changes unless you explicitly ask.
- Skill files: a SKILL.md for a specific recurring pattern (frequency of 3 or more).
- Prompt patches: one short paragraph per issue, appended to the system prompt.
- Knowledge entries: a JSON record with id, category, insight, source and confidence.
- Do nothing: for one-off or cosmetic issues, or fixes that are too broad or risky.
## Observations (Batch N)
### OBS-1: [Category] Short description
- Tasks affected: task_001, task_005, task_012
- Root cause: ...
- Frequency: 3/50 tasks (6%)
- Severity: degradingUse it with AutoResearchClaw
If you run the AutoResearchClaw (ARC) pipeline, the skill maps its loop onto specific stages. Stage 12 (EXPERIMENT_RUN) provides the Solve artifacts, stage 13 (ITERATIVE_REFINE) is the main Observe and Evolve trigger, stage 15 (RESEARCH_DECISION) works as a natural gate where PROCEED means accept and REFINE means retry, and stage 18 (PEER_REVIEW) adds signal about writing quality.
For ARC projects, the skill recommends locations for each artifact: evolved skills go in .claude/skills/evolved/<skill-name>/SKILL.md, knowledge entries in docs/kb/evolved_knowledge/<id>.json, and observation logs in evolution/observations/<batch>.md.
- Say "evolve my research pipeline" and the agent will ask which run to analyse, or find the latest artifacts/rc-*/ folder.
- Look for evolve.log, stage logs, reviews.md and sentinel watchdog reports.
- Prompt patches are appended to prompts.default.yaml or a custom prompts file.
Optional: MetaClaw integration
If AutoResearchClaw has MetaClaw enabled with metaclaw_bridge.enabled set to true, evolved skills can be placed in ~/.metaclaw/skills/arc-*/ so MetaClaw injects them into future runs automatically. The skill describes the two systems as complementary: a-evolve produces higher-precision targeted skills, while MetaClaw lessons capture broader patterns from pipeline warnings and errors.
metaclaw_bridge.enabled: trueSafety notes and tips
The skill runs no scripts and uses no network access. It works by reading the files you supply and writing proposed artifacts. Nothing is applied automatically: the gate step is a judgment check made by the agent, so you should review each change before it reaches a production prompt or skill set.
Keep a running evolution log, as the skill recommends, so you can trace which change came from which observation. Compare results after each change by re-running the failed tasks.
- Review every proposed artifact before placing it in a live project.
- Do not use the skill's output unchecked in production systems, where a mistaken edit could cause regressions.
- Give it real run data; a vague description produces vague skills.
- Ask for one batch at a time so observations stay tied to specific evidence.
What people use it for
- Finding recurring failure patterns, such as API pagination errors, across many runs of an experiment.
- Writing a short system prompt patch to fix ambiguous guidance that causes the same mistake repeatedly.
- Improving weak stages of an AutoResearchClaw research pipeline using experiment outputs and peer review feedback.
- Keeping a dated log of what changed in an agent's prompts and skills over time.
- Recording reusable experiment-design insights as JSON knowledge entries for future runs.
Frequently asked questions
Is the a-evolve skill free and what is its licence?
The skill is listed under the MIT licence in the aiming-lab/AutoResearchClaw repository. The source material does not state any price, so check the repository for licence terms before reuse.
What do I need to use the a-evolve skill?
You need an AI agent runtime that reads SKILL.md files and run logs, error traces or experiment outputs to analyse. AutoResearchClaw project layout is optional and only needed for pipeline-specific paths. MetaClaw with metaclaw_bridge.enabled is optional and only used for automatic injection of evolved skills.
Does the a-evolve skill change my agent's code?
No, not unless you explicitly ask. The skill is instructions only. It reads your logs and writes proposed skill files, prompt additions and knowledge entries for you to review.
Where do I put the a-evolve skill folder?
Unzip it into ~/.claude/skills/ for a personal install or into a project's .claude/skills/ folder. In the Claude apps, you can upload it under Settings → Capabilities → Skills.
Why won't the skill fix a one-off error?
The skill is designed to ignore one-off or cosmetic issues because generating fixes for them adds noise. It focuses on recurring patterns, typically with a frequency of three or more.
How does a-evolve compare with MetaClaw?
The skill produces higher-precision, targeted mutations from structured observation. MetaClaw lessons capture broader patterns from pipeline warnings and errors. The skill describes them as complementary and says both can coexist.
New agent skills, repos and AI tools — every week
The best new skills and open-source projects, the fastest-growing repos, and one free prompt. Five minutes to read. Unsubscribe anytime.
Our verdict
Use the a-evolve skill if you run repeated AI agent experiments or AutoResearchClaw pipelines and want a disciplined way to turn recurring failures into reviewed fixes. Skip it for one-off bugs, cosmetic issues, or production systems where prompt and skill changes would go live without human review.
Download the skill