Replication Driven Research
brycewang-stanford/Auto-Empirical-Research-Skills
A skill your agent uses when starting empirical analysis, creating a data pipeline, generating results, or when data or model specifications change.
Functional programming patterns with immutable data. An agent skill from citypaul/.dotfiles.
Install Functional
$ npx skills add citypaul/.dotfiles --skill functional -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install citypaul/.dotfiles functional --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/citypaul/.dotfiles.git skills-src && mkdir -p .claude/skills && cp -r skills-src/claude/.claude/skills/functional .claude/skills/functional && 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 "functional" agent skill from https://github.com/citypaul/.dotfiles/tree/main/claude/.claude/skills/functional into .claude/skills/functional/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "functional", 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/citypaul/.dotfiles/tree/main/claude/.claude/skills/functionalType 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 citypaul/.dotfiles --skill functional -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install citypaul/.dotfiles functional --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/citypaul/.dotfiles.git skills-src && mkdir -p .agents/skills && cp -r skills-src/claude/.claude/skills/functional .agents/skills/functional && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "functional" agent skill from https://github.com/citypaul/.dotfiles/tree/main/claude/.claude/skills/functional into .agents/skills/functional/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "functional", 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 citypaul/.dotfiles --skill functional -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install citypaul/.dotfiles functional --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/citypaul/.dotfiles.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/claude/.claude/skills/functional .cursor/skills/functional && 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 "functional" agent skill from https://github.com/citypaul/.dotfiles/tree/main/claude/.claude/skills/functional into .cursor/skills/functional/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "functional", 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/citypaul/.dotfiles.git --path claude/.claude/skills/functional--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 citypaul/.dotfiles --skill functional -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install citypaul/.dotfiles functional --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/citypaul/.dotfiles.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/claude/.claude/skills/functional .gemini/skills/functional && 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 "functional" agent skill from https://github.com/citypaul/.dotfiles/tree/main/claude/.claude/skills/functional into .gemini/skills/functional/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "functional", 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 citypaul/.dotfiles functionalInstalls 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 citypaul/.dotfiles --skill functional -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/citypaul/.dotfiles.git skills-src && mkdir -p .github/skills && cp -r skills-src/claude/.claude/skills/functional .github/skills/functional && 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 "functional" agent skill from https://github.com/citypaul/.dotfiles/tree/main/claude/.claude/skills/functional into .github/skills/functional/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "functional", 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 citypaul/.dotfiles --skill functional -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install citypaul/.dotfiles functional --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/citypaul/.dotfiles.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/claude/.claude/skills/functional .opencode/skills/functional && 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 "functional" agent skill from https://github.com/citypaul/.dotfiles/tree/main/claude/.claude/skills/functional into .opencode/skills/functional/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "functional", 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
functional- GitHub stars
- 740
- Token cost
- ~3.6k tokens
- SKILL.md length
- 1,299 words
- Files
- 4
- Skills in repo
- 44
- Repo updated
- First seen
- Licence
- Custom licence
At a glance
Functional programming patterns with immutable data. An agent skill from citypaul/.dotfiles.
- Works in 3 steps: No side effects - doesn't mutate… → Deterministic - same input → same… → Referentially transparent - can replace…
- Data transformations
- SKILL.md covers Core Principles, Why Immutability Matters, Functional Light and Self-Documenting Code and…, plus 6 more sections
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
What it does
Functional is an agent skill from citypaul/.dotfiles. Functional programming patterns with immutable data. Use when writing logic, data transformations, or encountering mutation bugs — including any feature request that builds, merges, filters, sorts, prices or otherwise reshapes records, lists, carts, orders or invoices, even when it never mentions immutability; load it alongside tdd for such changes, not instead of it. Covers immutability violations catalog, pure functions, composition, early returns, and options objects. Also use when composing Effect programs or…
Its SKILL.md is about 3.6k tokens, which your agent loads only when the skill is triggered. The skill folder holds 4 other files (for example `resources/composition-patterns.md`, `resources/effect-runtime.md` and `resources/immutability-catalog.md`).
It sits in Testing & QA, covering Data cleaning, Forms and invoices and Test-driven development.
When your agent uses it
- Data transformations
- Encountering mutation bugs — including any feature request that builds
- Otherwise reshapes records
- Even when it never mentions immutability
Example prompts
- “/functional”
Workflow steps
3 steps, taken from the first numbered list in SKILL.md.
- No side effects - doesn't mutate external state, modify arguments, or perform I/O
- Deterministic - same input → same output; no dependency on Date.now(), Math.random(), or globals
- Referentially transparent - can replace the call with its return value
What it can do on your machine
Read from SKILL.md and the folder at commit cd4028d. 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 (its code samples are typescript).
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
Functional loads about 3.6k tokens when it runs. Until then it costs about 174 tokens; SKILL.md has 1,299 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 1,299 words (~3,570 tokens).
“Deep-dive resources are in the resources/ directory. Load them on demand:”
- name
- functional
Files
SKILL.md and 3 other files in claude/.claude/skills/functional of citypaul/.dotfiles.
- SKILL.md
- resources/composition-patterns.md
- resources/effect-runtime.md
- resources/immutability-catalog.md
Open the folder on GitHubat commit cd4028d
Compare with similar skills
Functional 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 |
|---|---|---|---|---|---|---|
| Functional this skillcitypaul/.dotfiles | 740 | — | ~3.6k | Automated safety check: Pass | Custom licence | |
| Replication Driven Researchbrycewang-stanford/Auto-Empirical-Research-Skills | 4.5k | — | ~1.7k | Automated safety check: Pass | Custom licence | |
| Extract Document Datasickn33/agentic-awesome-skills | 47k | 1 repos | ~1.1k | Automated safety check: Pass | Apache-2.0 | |
| Playwright CLIsanity-io/sanity | 6.4k | 18 repos | ~1.9k | Automated safety check: Pass | MIT | |
| TDDpietheinstrengholt/rssmonster | 564 | 30 repos | ~906 | Automated safety check: Pass | MIT | |
| TDD WorkflowhellangleZ/burn-in-cceverywhere-ralph | 112 | 11 repos | ~2.4k | Automated safety check: Pass | None |
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TDD
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Test-driven development. An agent skill from pietheinstrengholt/rssmonster.
TDD Workflow
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A skill your agent uses when writing new features, fixing bugs, or refactoring code.
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Related
Questions about Functional
What does Functional do?
Functional programming patterns with immutable data. An agent skill from citypaul/.dotfiles. dotfiles. Functional programming patterns with immutable data.
When should I use Functional?
Functional fits situations like: data transformations; encountering mutation bugs — including any feature request that builds; otherwise reshapes records; even when it never mentions immutability.
How do I install Functional in Claude Code?
Run `npx skills add citypaul/.dotfiles --skill functional -a claude-code`. Or copy the skill folder (claude/.claude/skills/functional in citypaul/.dotfiles) into .claude/skills/functional in your project. Claude Code loads it when a task matches its description.
How do I install Functional in Codex?
Run `npx skills add citypaul/.dotfiles --skill functional -a codex`. Or copy the skill folder (claude/.claude/skills/functional in citypaul/.dotfiles) into .agents/skills/functional in your project. Codex loads it when a task matches its description.
Can I use Functional 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 citypaul/.dotfiles --skill functional -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/functional, .gemini/skills/functional, .github/skills/functional and .opencode/skills/functional in your project.
What does Functional need to run?
SKILL.md names no scripts, command-line tools or credentials: Functional is instructions for the agent only.
Does Functional 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 Functional 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 Functional use?
Functional 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 Functional use?
About 3.6k tokens (SKILL.md is roughly 14k 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 Functional?
Skills that share tags, products or a category with Functional: Replication Driven Research (brycewang-stanford/Auto-Empirical-Research-Skills, 4.5k stars), Extract Document Data (sickn33/agentic-awesome-skills, 47k stars), Playwright CLI (sanity-io/sanity, 6.4k stars) and TDD (pietheinstrengholt/rssmonster, 564 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Functional?
citypaul (a GitHub user) maintains it in citypaul/.dotfiles, which has 740 GitHub stars. The repository holds 44 skills in this directory. The repository was last updated on October 9, 2026.
Source: citypaul/.dotfiles on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.