A free skill you add to Claude

Make Claude read the official source first.

Each answer links the official page behind it, and flags anything Claude could not confirm there.

Download the skill View on GitHub

Claude tells you where each fact came from.

Each fact gets one of four labels.

It works for prices, laws, deadlines, and scores.

Claude reads the page of whoever is in charge of the fact: the maker, the store, the agency, the league.

Claude looks things up the same way every time.

Seven steps, each shown on a question Claude answered.

Fast answers still get checked.

You can set Claude to low effort for faster answers. Claude then checks less. With the skill, it still reads the source.

See the page behind a fact.

When a fact has no official source, Claude uses the best evidence.

Claude tells you what it used.

When the official page doesn't have the answer, Claude says so.

Apple's spec pages don't list the iPhone 15's battery capacity.

The skill stays out of everyday chat.

It skips opinions, brainstorming, creative writing, and common knowledge.

Claude tells you what it could not confirm.

Before it answers, Claude checks its own work four ways. Here it could not open the official site, and it said so.

Ask for it by name to be sure it runs.

Claude sometimes skips a skill. Type /horses-mouth in Claude Code. In the Claude apps, ask Claude to use the horses-mouth skill.

The skill is one short page of steps. Read it here.

Install the skill. Ask for a fact.

  1. 1
    Download the skill

    It's one zip file.

  2. 2

    Turn on code execution

    It's in your settings. Skills need it.

  3. 3

    Upload the zip

    Go to Customize, then Skills. Click +, then Create skill, then Upload a skill.