Claude Code Agent Development
anthropics/claude-plugins-official
Explains how to write agents for Claude Code plugins: the markdown file with YAML frontmatter, trigger descriptions, model and color settings, and system prompt design.
Subagent constraints specific to the GnollHack client repository.
Install Client Subagent Guidelines
$ npx skills add hyvanmielenpelit/GnollHack --skill client-subagent-guidelines -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install hyvanmielenpelit/GnollHack client-subagent-guidelines --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/hyvanmielenpelit/GnollHack.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.claude/skills/client-subagent-guidelines .claude/skills/client-subagent-guidelines && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "client-subagent-guidelines" agent skill from https://github.com/hyvanmielenpelit/GnollHack/tree/master/.claude/skills/client-subagent-guidelines into .claude/skills/client-subagent-guidelines/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "client-subagent-guidelines", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/hyvanmielenpelit/GnollHack/tree/master/.claude/skills/client-subagent-guidelinesType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add hyvanmielenpelit/GnollHack --skill client-subagent-guidelines -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install hyvanmielenpelit/GnollHack client-subagent-guidelines --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/hyvanmielenpelit/GnollHack.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.claude/skills/client-subagent-guidelines .agents/skills/client-subagent-guidelines && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "client-subagent-guidelines" agent skill from https://github.com/hyvanmielenpelit/GnollHack/tree/master/.claude/skills/client-subagent-guidelines into .agents/skills/client-subagent-guidelines/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "client-subagent-guidelines", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add hyvanmielenpelit/GnollHack --skill client-subagent-guidelines -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install hyvanmielenpelit/GnollHack client-subagent-guidelines --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/hyvanmielenpelit/GnollHack.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.claude/skills/client-subagent-guidelines .cursor/skills/client-subagent-guidelines && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "client-subagent-guidelines" agent skill from https://github.com/hyvanmielenpelit/GnollHack/tree/master/.claude/skills/client-subagent-guidelines into .cursor/skills/client-subagent-guidelines/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "client-subagent-guidelines", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/hyvanmielenpelit/GnollHack.git --path .claude/skills/client-subagent-guidelines--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add hyvanmielenpelit/GnollHack --skill client-subagent-guidelines -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install hyvanmielenpelit/GnollHack client-subagent-guidelines --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/hyvanmielenpelit/GnollHack.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.claude/skills/client-subagent-guidelines .gemini/skills/client-subagent-guidelines && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "client-subagent-guidelines" agent skill from https://github.com/hyvanmielenpelit/GnollHack/tree/master/.claude/skills/client-subagent-guidelines into .gemini/skills/client-subagent-guidelines/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "client-subagent-guidelines", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install hyvanmielenpelit/GnollHack client-subagent-guidelinesInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add hyvanmielenpelit/GnollHack --skill client-subagent-guidelines -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/hyvanmielenpelit/GnollHack.git skills-src && mkdir -p .github/skills && cp -r skills-src/.claude/skills/client-subagent-guidelines .github/skills/client-subagent-guidelines && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "client-subagent-guidelines" agent skill from https://github.com/hyvanmielenpelit/GnollHack/tree/master/.claude/skills/client-subagent-guidelines into .github/skills/client-subagent-guidelines/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "client-subagent-guidelines", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add hyvanmielenpelit/GnollHack --skill client-subagent-guidelines -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install hyvanmielenpelit/GnollHack client-subagent-guidelines --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/hyvanmielenpelit/GnollHack.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.claude/skills/client-subagent-guidelines .opencode/skills/client-subagent-guidelines && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "client-subagent-guidelines" agent skill from https://github.com/hyvanmielenpelit/GnollHack/tree/master/.claude/skills/client-subagent-guidelines into .opencode/skills/client-subagent-guidelines/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "client-subagent-guidelines", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
client-subagent-guidelines- GitHub stars
- 161
- Token cost
- ~222 tokens
- SKILL.md length
- 51 words
- Files
- 1
- Skills in repo
- 11
- Repo updated
- First seen
- Licence
- Custom licence
At a glance
Subagent constraints specific to the GnollHack client repository.
- Tasks that involve Subagents
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
What it does
Client Subagent Guidelines is an agent skill from hyvanmielenpelit/GnollHack. Subagent constraints specific to the GnollHack client repository. Covers the three build dependency chains that must not be parallelized across -- makedefs to generated headers to C interop, des files to levcomp to dlb, and GnollHackX XAML to makedefsdroid to GnollHackM -- and why cross-layer interop work in this repository escalates to the deep tier far more often than elsewhere. Read when writing a plan's Subagent Use section for GnollHack.
Its SKILL.md is about 220 tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.
It sits in Agent Workflows, covering Subagents. It works with C#. The repository describes itself as: Modern evolution of the classic roguelike game NetHack.
When your agent uses it
- Tasks that involve Subagents
Example prompts
- “/client-subagent-guidelines”
What it can do on your machine
Read from SKILL.md and the folder at commit 9df8a69. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md.
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Client Subagent Guidelines loads about 222 tokens when it runs. Until then it costs about 119 tokens; SKILL.md has 51 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check passed
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
Its licence (Custom licence) doesn't allow us to republish the file, so here is its outline and opening line. It has 51 words (~222 tokens).
“The full skill lives in this repository's tool-neutral agent directory (.agents/), which is shared with other AI coding agents. This file is only a pointer.”
- name
- client-subagent-guidelines
Files
Just SKILL.md in .claude/skills/client-subagent-guidelines of hyvanmielenpelit/GnollHack.
Open the folder on GitHubat commit 9df8a69
Compare with similar skills
Client Subagent Guidelines next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Client Subagent Guidelines this skillhyvanmielenpelit/GnollHack | 161 | — | ~222 | Automated safety check: Pass | Custom licence | |
| Claude Code Agent Developmentanthropics/claude-plugins-official | 38k | 7 repos | ~2.8k | Automated safety check: Pass | Apache-2.0 | |
| Subagent Driven DevelopmentAsvarox/allkaraoke | 261 | 37 repos | ~1.2k | Automated safety check: Pass | None | |
| Dispatching Parallel Agentsultralisp/ultralisp | 258 | 40 repos | ~1.5k | Automated safety check: Pass | None | |
| Paseo Advisor Second Opiniongetpaseo/paseo | 20k | 1 repos | ~756 | Automated safety check: Pass | Custom licence | |
| Task Observerrebelytics/one-skill-to-rule-them-all | 3.2k | 1 repos | ~12k | Automated safety check: Pass | CC-BY-4.0 |
Similar skills
- Official
Subagent Driven Development
Asvarox/allkaraoke
A skill your agent uses when executing implementation plans with independent tasks in the current session
Dispatching Parallel Agents
ultralisp/ultralisp
A skill your agent uses when facing 2+ independent tasks that can be worked on without shared state or sequential dependencies
Paseo Advisor Second Opinion
getpaseo/paseo
Launches one separate agent through Paseo to give a second opinion on the current task, with a self-contained briefing and no permission to edit files.
Task Observer
rebelytics/one-skill-to-rule-them-all
Monitors task execution for skill improvement opportunities.
O2 Review Loop
openobserve/openobserve
Splits a change into planner, coder and independent reviewer roles: you confirm a spec, a subagent implements it, and a separate reviewer checks each round's local WIP commit.
More from hyvanmielenpelit/GnollHack
All 11 skills in this repoClient Implementation Planning
hyvanmielenpelit/GnollHack
Implementation planning overlay for the GnollHack client repository.
Sentry Crash Analysis
hyvanmielenpelit/GnollHack
Systematic methodology for diagnosing GnollHack crash reports from the Sentry MCP server.
Adding Game Content
hyvanmielenpelit/GnollHack
Patterns for adding monsters, objects, and artifacts to GnollHack.
Build Pipeline
hyvanmielenpelit/GnollHack
Guide on building GnollHack native C libraries, processing assets with makedefs/levcomp/dgncomp/dlb, packaging nhdat, and compiling the C .NET MAUI frontend for Android, iOS, and Windows.
C Code Documentation
hyvanmielenpelit/GnollHack
Best practices for AI agents documenting the GnollHack C codebase.
Csharp Code Documentation
hyvanmielenpelit/GnollHack
Best practices for AI agents documenting the GnollHack C .NET MAUI codebase.
Related
Works with
Categories
Questions about Client Subagent Guidelines
What does Client Subagent Guidelines do?
Subagent constraints specific to the GnollHack client repository. Client Subagent Guidelines is an agent skill from hyvanmielenpelit/GnollHack. Subagent constraints specific to the GnollHack client repository.
When should I use Client Subagent Guidelines?
Client Subagent Guidelines fits situations like: tasks that involve Subagents.
How do I install Client Subagent Guidelines in Claude Code?
Run `npx skills add hyvanmielenpelit/GnollHack --skill client-subagent-guidelines -a claude-code`. Or copy the skill folder (.claude/skills/client-subagent-guidelines in hyvanmielenpelit/GnollHack) into .claude/skills/client-subagent-guidelines in your project. Claude Code loads it when a task matches its description.
How do I install Client Subagent Guidelines in Codex?
Run `npx skills add hyvanmielenpelit/GnollHack --skill client-subagent-guidelines -a codex`. Or copy the skill folder (.claude/skills/client-subagent-guidelines in hyvanmielenpelit/GnollHack) into .agents/skills/client-subagent-guidelines in your project. Codex loads it when a task matches its description.
Can I use Client Subagent Guidelines in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add hyvanmielenpelit/GnollHack --skill client-subagent-guidelines -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/client-subagent-guidelines, .gemini/skills/client-subagent-guidelines, .github/skills/client-subagent-guidelines and .opencode/skills/client-subagent-guidelines in your project.
What does Client Subagent Guidelines need to run?
SKILL.md names no scripts, command-line tools or credentials: Client Subagent Guidelines is instructions for the agent only.
Does Client Subagent Guidelines access the network?
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Is Client Subagent Guidelines safe to install?
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
What licence does Client Subagent Guidelines use?
Client Subagent Guidelines has a licence file (the repository's licence) that doesn't match a standard licence. Read it on GitHub before reusing the skill.
How many tokens does Client Subagent Guidelines use?
About 222 tokens (SKILL.md is roughly 888 characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
What are the alternatives to Client Subagent Guidelines?
Skills that share tags, products or a category with Client Subagent Guidelines: Claude Code Agent Development (anthropics/claude-plugins-official, 38k stars), Subagent Driven Development (Asvarox/allkaraoke, 261 stars), Dispatching Parallel Agents (ultralisp/ultralisp, 258 stars) and Paseo Advisor Second Opinion (getpaseo/paseo, 20k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Client Subagent Guidelines?
hyvanmielenpelit (a GitHub organization) maintains it in hyvanmielenpelit/GnollHack, which has 161 GitHub stars. The repository holds 11 skills in this directory. The repository was last updated on October 7, 2026.
Source: hyvanmielenpelit/GnollHack on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.