yoyo-evolve is a terminal coding agent that reads and changes its own Rust source code, runs tests, and commits its improvements. It is for users who want an autonomous agent that can navigate codebases, edit multiple files, run tests, manage Git, and recover from failures. The catalogue entries are skills for working with this coding agent.
Borrowing it
Nothing to install: this file belongs to yologdev/yoyo-evolve. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/yologdev/yoyo-evolve/main/CLAUDE.mdgit clone --depth 1 https://github.com/yologdev/yoyo-evolveWrote 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/instructions/yologdev/yoyo-evolve/claude-md)<a href="https://agentmods.dev/instructions/yologdev/yoyo-evolve/claude-md"><img src="https://agentmods.dev/badge/instructions/yologdev/yoyo-evolve/claude-md/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/instructions/yologdev/yoyo-evolve/claude-md"><img src="https://agentmods.dev/badge/instructions/yologdev/yoyo-evolve/claude-md.svg" alt="Reviewed on agentmods" width="80" 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 5.1 | $0.09792 | $0.09792 |
| Opus 5.5 | $0.03917 | $0.03917 |
| Sonnet 5.5 | $0.01958 | $0.01958 |
| Haiku 4.5 | $0.00979 | $0.00979 |
Grade A, and why
yoyo-evolve CLAUDE.md 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 yesterday.
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 — 188 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
What This Is
A self-evolving coding agent CLI built on yoagent. The agent spans multiple Rust source files under src/. A GitHub Actions cron job (scripts/evolve.sh) runs the agent on a schedule using a 3-phase pipeline (plan → implement → respond), which reads its own source, picks improvements, implements them, and commits — if tests pass. The cadence and the model are parameters, not facts about this project, and they are deliberately not written down here. The schedule lives in .github/workflows/evolve.yml (schedule.cron) and the provider, model and their knobs in .yoyo.toml only — every script and workflow reads the model from there (a MODEL env var overrides one run; there is no MODEL secret, and tests/harness_logic.sh fails if a model id is hardcoded anywhere else, because provider in one place and model in another is how Days 210-211 sent a DeepSeek id to Anthropic). Read those rather than this file, because a value copied into prose goes stale silently while the config keeps working. Two things about that config are not derivable from reading it, so they are recorded here instead:
- The provider-key line in every workflow is load-bearing, not tidiness. yoyo's key lookup falls back to
ANTHROPIC_API_KEYand thenAPI_KEYwhen the configured provider's own variable is unset, so a workflow that forgets to export the provider's key does not fail loudly — it sends the wrong provider's token and gets a 401. Every workflow that runs yoyo must export the key for whichever provider.yoyo.tomlnames. thinking = "high"is still the top rung yoyo sends, but now by yoyo's choice, not yoagent's limit. Superseded claim (yoagent 0.24.0 upgrade, Day 218, #987), recorded rather than erased: this bullet said yoagent 0.18.1 had nothing aboveHigh. Since 0.19ThinkingLevelhasXHighandMax(#[non_exhaustive]), and on OpenAI-compatible providersMaxcan go out asmax. yoyo itself still foldsmaxtoHighinsrc/cli.rs/src/config.rs; sending a higher tier is a priced decision that has not been made .
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.
- yesterday Changed · +154 tokens per session cec4d9543e41
- 2d ago Changed · +62 tokens per session 6f8f6f1238ac
- 6d ago Changed · +2 lines · +69 tokens per session cb76abb92d87
- 7d ago Changed 859537bf9554
- 13d ago Changed b6e320b496b0
- 14d ago Changed · +74 tokens per session 03079216a6b8
- 21d ago Changed · +12 lines · +549 tokens per session 75a24923ccc0
- 1mo ago Changed · +5 lines · -127 tokens per session 20efe0edc0df
- 1mo ago First seen · 169 lines · 9,011 tokens per session scan A 78701b2472b1
yoyo-evolve CLAUDE.md is an instructions file published in the GitHub repository yologdev/yoyo-evolve (1,915 stars, last pushed today), licensed MIT. It adds 9,792 tokens to every session, about $0.0392 per session on Opus 5.5. 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 2026-09-16.
Other instructions, from other repositories
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, cache eligibility and rollout and applying the notice (cutover).
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
vscode copilot-instructions.md
Copilot instructions for microsoft/vscode, covering vs code copilot instructions, project overview, root folders, core architecture (src/ folder) and built-in extensions (extensions/ folder).
deepseek-harness AGENTS.md
AGENTS.md instructions for deepseek-ai/deepseek-harness, covering agents.md, pre-stable apis and released session data, repository layout, commands and host sandbox failures.