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Fact-Check Claims Skill

Verifies every factual claim in content against live sources before it ships.

Source Download skill
Repository
garrytan/gbrain
Stars
31,447
Licence
MIT
Files
1 file

What it does

When installed, the agent goes through a draft claim by claim, pulling out names, numbers, quotes, dates and superlatives, then checks each one against live web sources rather than its own memory. It labels each claim on a six-level confidence scale, suggests corrections or hedged wording, and produces a pass/fail report. For outputs generated from a brain or database, it also re-derives key claims through a separate query path before allowing delivery.

Great for

  • Writers and editors checking an essay, article or blog post before publishing
  • Anyone producing a briefing or report that must be factually reliable
  • Teams wanting a repeatable checklist for verifying AI-generated output

Skip it if

  • Opinion pieces or creative fiction, where the skill deliberately skips opinions and predictions and adds little value
  • Situations needing guaranteed truth: it depends on the quality and availability of web sources and can still miss errors or report false negatives
  • Highly confidential content, since claims and some context may be sent to web search and fetch tools

Try asking

  • “Fact check this draft article before I publish it”
  • “Verify the facts and statistics in this report claim by claim”
  • “Is this accurate? Check every number and quote in this press release”
  • “Re-derive every claim in this summary generated from our database”
Step-by-step guide: how to use Fact-Check Claims SkillInstall, first run, examples, tips and FAQs

Install in 3 steps

  1. 1

    Download the skill

    The ZIP contains the 1 original files, the MIT licence and an attribution note.

    fact-check.zip
  2. 2

    Add it to your agent

    Claude Code (all projects)

    mkdir -p ~/.claude/skills && unzip fact-check.zip -d ~/.claude/skills/

    Claude Code / Agent SDK (this project only)

    mkdir -p .claude/skills && unzip fact-check.zip -d .claude/skills/

    Claude apps (web/desktop): Settings → Capabilities → Skills → Upload skill, and choose the ZIP.

  3. 3

    Ask for the task

    No special command needed — the agent reads the skill's description and loads it when your request matches. Try one of the prompts above.

Get better results

  • Provide the full text and any sources you already have so the agent can check them first.
  • Expect uncertain claims to be hedged rather than confirmed; review any UNVERIFIED or DISPUTED items yourself.
  • Do not rely on the skill alone for legal or defamation review; have a human editor check high-stakes claims.

What's inside

  • SKILL.md

Redistributed unmodified from garrytan/gbrain under the MIT licence. The assessment was drafted with AI from the skill's files on 2026-10-29. Skills can instruct your agent to run code — read SKILL.md and any scripts before installing.