Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/kitchen-engineer42/joharnessburg/skill-evolutionnpx skills add kitchen-engineer42/joharnessburg --skill skill-evolutiongit clone --depth 1 https://github.com/kitchen-engineer42/joharnessburgWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/kitchen-engineer42/joharnessburg/skill-evolution)<a href="https://agentmods.dev/skills/kitchen-engineer42/joharnessburg/skill-evolution"><img src="https://agentmods.dev/badge/skills/kitchen-engineer42/joharnessburg/skill-evolution.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00153 | $0.02357 |
| Opus 5 | $0.00077 | $0.01179 |
| Sonnet 5 | $0.00031 | $0.00471 |
| Haiku 4.5 | $0.00015 | $0.00236 |
Grade A, and why
skill-evolution scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 100 lines — stays where its author put it; the contents beside it link to each section on GitHub.
skill-evolution
A skill document is not finished at authoring time — it should earn its content from run evidence. John structures that earning as evolution rings: the closer a text is to the work, the faster and more automated its evolution may be; the more meta it is, the slower and more human-gated.
- Ring 0 — this project (you, this skill): lessons, project-local override drafts, and the worker-skill training loop. Blast radius: this project only.
- Ring 1 — the template: the template's owner evolves it from accumulated run reports across projects. You feed Ring 1 (lessons, reports); you never edit the template itself.
- Ring 2 — John core: the maintainers evolve the teaching skills from cross-domain evidence. You feed it the same way. The top gate is human, permanently.
Your influence travels upward as evidence, never as edits. This skill teaches Ring 0: what to capture, what you may change, how to change it safely, and how to train the one class of skill where a real optimization loop applies.
The boundary: trainable vs teaching
Before touching any skill text, classify it:
Could a different domain's template author have legitimately written this passage differently? Then it's trainable — domain-specific "what to do", fair game for Ring-0 drafts and the training loop. Is it true in every domain? Then it's teaching — core methodology, hands off; if it's wrong, that's a
core-scope lesson, not an edit.
In practice the trainable surface is what the template changed relative to vanilla John (its overrides, additive skills, plan skeleton, agents, worker prompts — enumerated in the applied plugin's .applied-metadata.json) plus anything project-local you created. When in doubt: log a lesson, don't edit.
A second classification, for deciding where an improvement lands (it shapes your lesson's scope_guess, and Ring 1 uses it when folding lessons in):
- Core assets of a template — its SKILL.md bodies, reusable scripts, the plan skeleton: things every project of this type needs. A lesson that generalizes across corpora of the domain points here.
- Perimeter assets —
references/depth, worked examples, edge-case notes: useful, loaded on demand. A lesson that's real but conditional points here. - Ad-hoc — judgment calls each project should make fresh. Not every lesson deserves to be institutionalized; over-folding kills the wide tunnel. It's legitimate for a lesson's destiny to be "stay project-local."
What ships with it
4 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 5d ago First seen · 100 lines · 153 tokens per session scan A f2bab03fb8bc
skill-evolution is a skill published in the GitHub repository kitchen-engineer42/joharnessburg (9 stars, last pushed 1mo ago), licensed MIT. It adds 153 tokens to every session and 2,357 once invoked, about $0.0008 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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