Githits Code
githits-com/githits-cli
A skill your agent uses whenever invoking the GitHits CLI for public OSS source, documentation, or example evidence, including code search/grep, file navigation, source verification, docs lookup, or…
Anti-hallucination discipline for any code that names an external symbol you aren't certain exists — a library function, method, config key, package version, CLI flag, env var, or endpoint.
Install Fact Checker
$ npx skills add ccplugins/awesome-claude-code-plugins --skill fact-checker -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install ccplugins/awesome-claude-code-plugins fact-checker --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/ccplugins/awesome-claude-code-plugins.git skills-src && mkdir -p .claude/skills && cp -r skills-src/plugins/bullpen/skills/fact-checker .claude/skills/fact-checker && 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 "fact-checker" agent skill from https://github.com/ccplugins/awesome-claude-code-plugins/tree/main/plugins/bullpen/skills/fact-checker into .claude/skills/fact-checker/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "fact-checker", 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/ccplugins/awesome-claude-code-plugins/tree/main/plugins/bullpen/skills/fact-checkerType 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 ccplugins/awesome-claude-code-plugins --skill fact-checker -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install ccplugins/awesome-claude-code-plugins fact-checker --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ccplugins/awesome-claude-code-plugins.git skills-src && mkdir -p .agents/skills && cp -r skills-src/plugins/bullpen/skills/fact-checker .agents/skills/fact-checker && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "fact-checker" agent skill from https://github.com/ccplugins/awesome-claude-code-plugins/tree/main/plugins/bullpen/skills/fact-checker into .agents/skills/fact-checker/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "fact-checker", 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 ccplugins/awesome-claude-code-plugins --skill fact-checker -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install ccplugins/awesome-claude-code-plugins fact-checker --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ccplugins/awesome-claude-code-plugins.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/plugins/bullpen/skills/fact-checker .cursor/skills/fact-checker && 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 "fact-checker" agent skill from https://github.com/ccplugins/awesome-claude-code-plugins/tree/main/plugins/bullpen/skills/fact-checker into .cursor/skills/fact-checker/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "fact-checker", 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/ccplugins/awesome-claude-code-plugins.git --path plugins/bullpen/skills/fact-checker--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 ccplugins/awesome-claude-code-plugins --skill fact-checker -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install ccplugins/awesome-claude-code-plugins fact-checker --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ccplugins/awesome-claude-code-plugins.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/plugins/bullpen/skills/fact-checker .gemini/skills/fact-checker && 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 "fact-checker" agent skill from https://github.com/ccplugins/awesome-claude-code-plugins/tree/main/plugins/bullpen/skills/fact-checker into .gemini/skills/fact-checker/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "fact-checker", 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 ccplugins/awesome-claude-code-plugins fact-checkerInstalls 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 ccplugins/awesome-claude-code-plugins --skill fact-checker -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/ccplugins/awesome-claude-code-plugins.git skills-src && mkdir -p .github/skills && cp -r skills-src/plugins/bullpen/skills/fact-checker .github/skills/fact-checker && 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 "fact-checker" agent skill from https://github.com/ccplugins/awesome-claude-code-plugins/tree/main/plugins/bullpen/skills/fact-checker into .github/skills/fact-checker/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "fact-checker", 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 ccplugins/awesome-claude-code-plugins --skill fact-checker -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install ccplugins/awesome-claude-code-plugins fact-checker --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ccplugins/awesome-claude-code-plugins.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/plugins/bullpen/skills/fact-checker .opencode/skills/fact-checker && 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 "fact-checker" agent skill from https://github.com/ccplugins/awesome-claude-code-plugins/tree/main/plugins/bullpen/skills/fact-checker into .opencode/skills/fact-checker/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "fact-checker", 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
fact-checker- GitHub stars
- 967
- Token cost
- ~1.4k tokens
- SKILL.md length
- 750 words
- Files
- 1
- Skills in repo
- 68
- Repo updated
- First seen
- Licence
- MIT
At a glance
Anti-hallucination discipline for any code that names an external symbol you aren't certain exists — a library function, method, config key, package version, CLI flag, env var, or endpoint.
- Works in 5 steps: Grep the codebase. The helper you're… → Read the installed package. Open… → Check the lockfile before you cite a… → …
- The user says fact-check
- SKILL.md covers When it fires, The move, Rules and Output, plus 3 more sections
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
What it does
Fact Checker is an agent skill from ccplugins/awesome-claude-code-plugins. Anti-hallucination discipline for any code that names an external symbol you aren't certain exists — a library function, method, config key, package version, CLI flag, env var, or endpoint. Before you call it, cite it, or import it, confirm it's real: grep the codebase, read the installed package's actual signature, check the lockfile. If you can't verify, write "unverified" instead of asserting. When memory and the repo disagree, the repo wins. Supports intensity levels: lite, full (default), ultra. Use whenever…
Its SKILL.md is about 1.4k 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 Development, covering Dependency management and Fact-checking and source verification. The repository describes itself as: Awesome Claude Code plugins — a curated list of slash commands, subagents, MCP servers, and hooks for Claude Code. The licence is MIT.
When your agent uses it
- The user says fact-check
- Verify this exists
- Did you make that up
- No hallucinations
Example prompts
- “s real: grep the codebase, read the installed package”
- “t verify, write”
- “fact-check”
- “/fact-checker”
Workflow steps
5 steps, taken from the first numbered list in SKILL.md.
- Grep the codebase. The helper you're about to call — does it exist, and is
- Read the installed package. Open node_modules / the venv / the source.
- Check the lockfile before you cite a version or flag. The version installed
- When memory and the repo disagree, the repo wins. Every time. Your training
- Can't verify it? Say so. Write the line and mark it unverified rather than
What it can do on your machine
Read from SKILL.md and the folder at commit 5bd4f16. 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
Fact Checker loads about 1.4k tokens when it runs. Until then it costs about 201 tokens; SKILL.md has 750 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
The full file from ccplugins/awesome-claude-code-plugins at commit 5bd4f16, republished under its MIT licence (© ccplugins). 750 words, ~1,407 tokens.
Download SKILL.mdSave it as
.claude/skills/fact-checker/SKILL.md (or your agent's skills folder).- name
- fact-checker
- description
- Anti-hallucination discipline for any code that names an external symbol you aren't certain exists — a library function, method, config key, package version, CLI flag, env var, or endpoint. Before you call it, cite it, or import it, confirm it's real: grep the codebase, read the installed package's actual signature, check the lockfile. If you can't verify, write "unverified" instead of asserting. When memory and the repo disagree, the repo wins. Supports intensity levels: lite, full (default), ultra. Use whenever the user says "fact-check", "verify this exists", "did you make that up", "check the API", "no hallucinations", or you're wiring up an unfamiliar library or codebase. Do NOT use for language keywords or stdlib you're certain of, or trivial code with no external symbols.
- argument-hint
- [lite|full|ultra]
- license
- MIT
The Fact-Checker
You are the pedant on the team who has never invented an API in his life. Where everyone else types the method name they're pretty sure exists and runs it, you open the source and read the signature first — every time, without apology. You'd rather spend ten seconds confirming than an hour debugging a name that was never real.
A plausible name is not a real name. The compiler doesn't care what you meant.
When it fires
Not every line has a fact to check. for, if, map, String.length — you
know those cold, and stopping to "verify" them is theater. The check fires the
moment you reach for a symbol you can't swear is real:
- a library function, method, or class from a third-party package
- a config key, option name, or default you're recalling from memory
- a package version, a CLI flag, an env var, an endpoint path
- a helper, constant, or type you assume the codebase already has
- anything you'd write because it fits the shape you want, not because you saw it
No external symbol in the line → nothing to check. Write it and move on. YAGNI applies to paranoia too.
The move
Before the call ships, confirm the symbol exists — don't trust the memory that supplied it:
- Grep the codebase. The helper you're about to call — does it exist, and is
its signature what you assumed?
grep -rn "functionName"beats faith. - Read the installed package. Open
node_modules/ the venv / the source. Check the real export and its arguments, not the one your memory reconstructed. - Check the lockfile before you cite a version or flag. The version installed is the truth; the version you remember is a guess.
- When memory and the repo disagree, the repo wins. Every time. Your training is a prior, not a source.
- Can't verify it? Say so. Write the line and mark it
unverifiedrather than assert a fiction with confidence.
Every check is specific to the symbol in front of you. One confirmed call beats ten elegant ones you imagined.
Rules
- Never invent an API to fit the shape you want. If the method you need doesn't exist, that's information — compose the real ones instead.
- A plausible name is not a real name.
readFileLines,parseAsync,client.getOrCreateall sound right; sounding right proves nothing. - Prefer the API you confirmed over the elegant one you imagined. Ugly and real beats clean and fictional.
- A confident wrong call costs an hour of debugging and burns the user's trust. The ten-second grep is the cheap side of that trade.
Show full SKILL.md (320 more words)Show less
Output
Code first, built from verified symbols. Then a short Checked: report — what you confirmed, how, and anything left unverified. If you couldn't verify a symbol, it's named here, not buried.
Pattern: [code] → Checked: [symbol confirmed via grep/source] · [version per lockfile] · [X unverified]
Intensity
| Level | What change |
|---|---|
| lite | Write it, but flag the one symbol you're least sure of — one line. User decides whether to verify. |
| full | Verify every uncertain external symbol before shipping, mark what you couldn't. Default. |
| ultra | Trust nothing from memory. Confirm every symbol against source, pin versions to the lockfile, and leave a line that fails loudly if a cited API drifts. |
Example — reading a file's lines in Node:
- lite: "Used
fs.readFileLines(path)— flagging it; I don't think Node'sfsactually has that. Verify before relying on it." - full: "Checked:
fs.readFileLinesisn't in Node'sfs— no such export. Replaced with the confirmedfs.readFileSync(path, 'utf8').split('\n').readFileSyncverified against thefsdocs / signature." - ultra: full, plus — grepped the codebase for an existing line-reader helper first (none), pinned to the Node version in
.nvmrc, and added a smoke test that reads a fixture so a future API swap fails in CI, not prod.
When NOT to
Skip it for language keywords and stdlib you genuinely know, throwaway snippets,
or symbols the surrounding code already proves exist. Don't perform verification
you don't need — re-confirming Array.map is noise. And never let "unverified"
become a shrug: if the user needs the call to be right, verify it or say plainly
that you couldn't. The human's explicit "just write it, I'll check" wins — note
the risk once, then comply.
Boundaries
The Fact-Checker governs whether the symbols you write are real, not how much you build — pair it with Chameleon, which makes sure the real symbol you found is also the house one. "stop fact-checker" / "normal mode": revert. Level persists until changed or session end.
It reads the docs so you don't debug the fiction.
© ccplugins, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Files
Just SKILL.md in plugins/bullpen/skills/fact-checker of ccplugins/awesome-claude-code-plugins.
Open the folder on GitHubat commit 5bd4f16
Compare with similar skills
Fact Checker 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 |
|---|---|---|---|---|---|---|
| Fact Checker this skillccplugins/awesome-claude-code-plugins | 967 | — | ~1.4k | Automated safety check: Pass | MIT | |
| Githits Codegithits-com/githits-cli | 114 | — | ~2.6k | Automated safety check: Pass | Apache-2.0 | |
| Phyai Communicate With Memorymingti-org/phyai | 128 | — | ~1.9k | Automated safety check: Pass | MIT | |
| Fact Checkerdaymade/claude-code-skills | 1.4k | 2 repos | ~2.1k | Automated safety check: Pass | MIT | |
| Dep Updatestrufflesecurity/trufflehog | 28k | — | ~1.3k | Automated safety check: Pass | AGPL-3.0 | |
| Add TTS Engine to Voiceboxjamiepine/voicebox | 57k | — | ~1.3k | Automated safety check: Pass | MIT |
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Questions about Fact Checker
What does Fact Checker do?
Anti-hallucination discipline for any code that names an external symbol you aren't certain exists — a library function, method, config key, package version, CLI flag, env var, or endpoint. Fact Checker is an agent skill from ccplugins/awesome-claude-code-plugins. Anti-hallucination discipline for any code that names an external symbol you aren't certain exists — a library function, method, config key, package version, CLI flag, env var, or endpoint.
When should I use Fact Checker?
Fact Checker fits situations like: the user says fact-check; verify this exists; did you make that up; no hallucinations.
How do I install Fact Checker in Claude Code?
Run `npx skills add ccplugins/awesome-claude-code-plugins --skill fact-checker -a claude-code`. Or copy the skill folder (plugins/bullpen/skills/fact-checker in ccplugins/awesome-claude-code-plugins) into .claude/skills/fact-checker in your project. Claude Code loads it when a task matches its description.
How do I install Fact Checker in Codex?
Run `npx skills add ccplugins/awesome-claude-code-plugins --skill fact-checker -a codex`. Or copy the skill folder (plugins/bullpen/skills/fact-checker in ccplugins/awesome-claude-code-plugins) into .agents/skills/fact-checker in your project. Codex loads it when a task matches its description.
Can I use Fact Checker 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 ccplugins/awesome-claude-code-plugins --skill fact-checker -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/fact-checker, .gemini/skills/fact-checker, .github/skills/fact-checker and .opencode/skills/fact-checker in your project.
What does Fact Checker need to run?
SKILL.md names no scripts, command-line tools or credentials: Fact Checker is instructions for the agent only.
Does Fact Checker 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 Fact Checker 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 Fact Checker use?
Fact Checker is published under the MIT licence (declared in SKILL.md). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Fact Checker use?
About 1.4k tokens (SKILL.md is roughly 5.6k 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 Fact Checker?
Skills that share tags, products or a category with Fact Checker: Githits Code (githits-com/githits-cli, 114 stars), Phyai Communicate With Memory (mingti-org/phyai, 128 stars), Fact Checker (daymade/claude-code-skills, 1.4k stars) and Dep Updates (trufflesecurity/trufflehog, 28k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Fact Checker?
ccplugins (a GitHub organization) maintains it in ccplugins/awesome-claude-code-plugins, which has 967 GitHub stars. The repository holds 68 skills in this directory. The repository was last updated on August 12, 2026.
Source: ccplugins/awesome-claude-code-plugins on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.