# Fact Check (agent skill)

> Fact Check is an agent skill (a SKILL.md file) from elvisun/newsjack. Extract factual claims from PR copy, verify each claim independently, attach concrete citations, and warn when certainty is low. It works with Claude Code and Codex and has 1,515 GitHub stars across a repository of 2 listed skills.

Extract factual claims from PR copy, verify each claim independently, attach concrete citations, and warn when certainty is low. Runs each claim through proven newsroom verification methods (lateral reading, source-tier climbing, provenance pillars, triangulation, calibrated rating) and puts the burden of proof on the speaker. Use before a pitch, press release, reactive comment, DM, or other journalist-facing draft is trusted or sent. You are the factual accuracy gate inside newsjack.sh.

## Key facts

| Fact | Value |
|---|---|
| Repository | https://github.com/elvisun/newsjack |
| Skill path | skills/fact-check/SKILL.md |
| Skill name | fact-check |
| GitHub stars | 1,515 |
| Installs on skills.sh | not listed |
| License | MIT |
| Skills in repo | 2 |
| Plugin marketplace | newsjack |
| Official | no |
| Works with | Claude Code, Codex |
| Category | Testing & QA |
| Last commit | Oct 7, 2026 |

## Add this skill

### Claude Code

```sh
/plugin marketplace add elvisun/newsjack
/plugin install newsjack@newsjack
```

In the Claude apps, zip the skill folder and upload it under Customize > Skills > + > Upload a skill (code execution must be on).

### ChatGPT / Codex

```sh
git clone --depth 1 https://github.com/elvisun/newsjack.git
cp -r newsjack/skills/fact-check .agents/skills/fact-check   # repo; ~/.agents/skills for all projects
```

### Cursor

```sh
git clone --depth 1 https://github.com/elvisun/newsjack.git
cp -r newsjack/skills/fact-check .cursor/skills/fact-check   # project; ~/.cursor/skills for all projects
```

Sources (checked 2026-10-07): https://code.claude.com/docs/en/skills, https://support.claude.com/en/articles/12512180-using-skills-in-claude, https://learn.chatgpt.com/docs/build-skills, https://cursor.com/docs/context/skills

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Canonical page: https://appsgit.com/skills/elvisun-fact-check
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