# Caveman Project Skills Documentation: Complete Guide to Claude Agent Modes > Explore the caveman project's skills documentation with our complete guide to Claude agent modes. Discover triggers, rules, and technical boundaries for efficient Claude interactions. - Repository: [Julius Brussee/caveman](https://github.com/JuliusBrussee/caveman) - Tags: documentation - Published: 2026-07-03 --- **Yes, the JuliusBrussee/caveman repository maintains comprehensive documentation for every skill through dedicated [`SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/SKILL.md) files located in the `skills/` directory, each defining triggers, rules, and technical boundaries for ultra‑compressed Claude interactions.** The caveman project skills documentation is embedded directly in the codebase rather than external wikis. Each skill is a self‑contained interaction mode that reduces token usage by approximately 65% while preserving technical accuracy. The documentation lives in structured markdown files paired with JavaScript hooks and agent definitions that govern how Claude processes slash commands like `/caveman` or `/caveman‑review`. ## What Are Caveman Skills? **Caveman skills** are ultra‑compressed interaction modes designed for Claude‑based agents. Each skill is defined by a [`SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/SKILL.md) file residing under `skills//SKILL.md`. These files follow a front‑matter format enclosed in triple dashes (`---`) that declares the skill’s name, description, and operational constraints. According to the caveman source code, skills implement specific boundaries—declaring explicitly what they do not do—to prevent side effects. For example, the `caveman‑commit` skill formats commit messages but never executes `git commit`. ## Available Skills and Documentation Locations The repository ships seven core skills, each with dedicated documentation: - **`caveman`** – The core compression mode that switches Claude to a terse speaking style. Documentation: [`skills/caveman/SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/skills/caveman/SKILL.md). - **`caveman‑commit`** – Generates Conventional‑Commit messages from diffs. Documentation: [`skills/caveman-commit/SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/skills/caveman-commit/SKILL.md). - **`caveman‑review`** – Produces one‑line, actionable code‑review comments. Documentation: [`skills/caveman-review/SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/skills/caveman-review/SKILL.md). - **`caveman‑stats`** – Displays token‑usage statistics for the current session. Documentation: [`skills/caveman-stats/SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/skills/caveman-stats/SKILL.md) (core) and [`plugins/caveman/skills/caveman-stats/SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/plugins/caveman/skills/caveman-stats/SKILL.md) (plugin version). - **`caveman‑help`** – Provides quick help about caveman modes. Documentation: [`skills/caveman-help/SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/skills/caveman-help/SKILL.md). - **`caveman‑compress`** – Handles markdown‑compression tasks such as todo‑list compression. Documentation: [`skills/caveman-compress/SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/skills/caveman-compress/SKILL.md). - **`cavecrew`** – A collection of auxiliary skills for internal agent use (builder, reviewer, investigator). Documentation: [`skills/cavecrew/SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/skills/cavecrew/SKILL.md). ## How Skill Documentation Is Structured The caveman project skills documentation follows a strict architecture that separates definitions from execution logic. ### SKILL.md Front‑Matter Format Each skill file begins with YAML front‑matter declaring metadata: ```markdown --- name: caveman description: Ultra‑compressed speaking mode --- ``` The remaining content describes triggers, rules, and boundaries in human‑readable markdown. ### Trigger Handling and Agents Slash commands like `/caveman lite|full|ultra` are processed by the *opencode* runtime. The `agents/` folder contains markdown agent files—such as `agents/cavecrew‑reviewer.md` and `agents/cavecrew‑builder.md`—that reference these skills and map user inputs to specific skill executions. ### Hooks for Computation Certain skills require JavaScript computation rather than pure prompt engineering. These are implemented in the `hooks/` directory: - **`hooks/caveman‑mode‑tracker.js`** – Tracks the active state of the caveman mode and manages persistence. - **`hooks/caveman‑stats.js`** – Calculates token usage and returns a `decision: "block"` containing formatted statistics. ### Persistence Mechanisms The core `caveman` skill marks itself **ACTIVE EVERY RESPONSE** according to its persistence section. Once enabled via `/caveman ultra`, the compression style persists across every subsequent response until the user explicitly disables it with `/caveman stop`. ## Practical Usage Examples ### Enabling Ultra Compression Mode To activate the terse speaking style: ```text /caveman ultra ``` The model now replies using the compressed pattern defined in [`skills/caveman/SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/skills/caveman/SKILL.md), reducing token consumption by approximately 65%. ### Generating Conventional Commit Messages Invoke the commit skill with a diff: ```text /caveman‑commit ``` The agent outputs a properly formatted message: ```markdown feat(api): add GET /users/:id/profile Mobile client needs profile data without the full payload. Closes #128 ``` ### Production Code Review Comments For concise pull request reviews: ```text /caveman‑review ``` The response follows the one‑line format specified in [`skills/caveman-review/SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/skills/caveman-review/SKILL.md): ```text L42: 🔴 bug: user can be null after .find(). Add guard before .email. ``` ### Checking Token Statistics To view session metrics without AI computation: ```text /caveman‑stats ``` The `hooks/caveman‑stats.js` hook injects a table showing total tokens used, saved, and projected savings. ## Summary - **Documentation location**: Every skill is documented in `skills//SKILL.md` with YAML front‑matter and markdown rules. - **Architecture**: Skills combine markdown definitions, agent triggers in `agents/`, and JavaScript hooks in `hooks/` for stateful operations. - **Token efficiency**: The core `caveman` skill reduces token usage by ~65% through ultra‑compressed output patterns. - **Persistence**: The caveman mode stays active across responses until explicitly stopped, managed by `hooks/caveman‑mode‑tracker.js`. - **Boundaries**: Each skill explicitly declares prohibited actions (e.g., `caveman‑commit` never executes git commands) to prevent side effects. ## Frequently Asked Questions ### Where is the caveman project skills documentation located? The documentation resides in the `skills/` directory of the JuliusBrussee/caveman repository. Each skill has its own subdirectory containing a [`SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/SKILL.md) file that defines triggers, rules, and boundaries. Additional implementation details appear in `hooks/` for JavaScript logic and `agents/` for trigger handling. ### How do I enable a specific skill in the caveman project? You enable skills by typing slash commands recognized by the *opencode* runtime. For example, use `/caveman ultra` to activate maximum compression, `/caveman‑review` for code review mode, or `/caveman‑stats` to see token usage. The commands are parsed and mapped to the corresponding [`SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/SKILL.md) definitions. ### What is the difference between a skill and an agent in the caveman repository? A **skill** is a documented interaction mode defined in [`SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/SKILL.md) files under `skills/`, specifying how Claude should behave and respond. An **agent** is a higher‑level construct in the `agents/` directory that references one or more skills to handle specific workflows, such as the `cavecrew‑reviewer` agent that utilizes the `caveman‑review` skill. ### Can I create custom skills for the caveman project? Yes. Create a new directory under `skills/` with a [`SKILL.md`](https://github.com/JuliusBrussee/caveman/blob/main/SKILL.md) file following the front‑matter format (`---` name and description `---`). Define your triggers, rules, and explicit boundaries. If your skill requires computation (like token counting), implement a corresponding hook in `hooks/` and reference it in your agent definitions.