Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add commands/sergei-aronsen/claude-code-toolkit/factcheckgit clone --depth 1 https://github.com/sergei-aronsen/claude-code-toolkitWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/commands/sergei-aronsen/claude-code-toolkit/factcheck)<a href="https://agentmods.dev/commands/sergei-aronsen/claude-code-toolkit/factcheck"><img src="https://agentmods.dev/badge/commands/sergei-aronsen/claude-code-toolkit/factcheck.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00000 | $0.00741 |
| Opus 5 | $0.00000 | $0.00370 |
| Sonnet 5 | $0.00000 | $0.00148 |
| Haiku 4.5 | $0.00000 | $0.00074 |
Grade A, and why
factcheck scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 118 lines — stays where its author put it; the contents beside it link to each section on GitHub.
/factcheck — Verify a Specific Claim with Sources
Purpose
Verify a single factual claim against current web sources. Returns a verdict
(VERIFIED, DISPUTED, UNVERIFIABLE) with supporting citations.
Built on the same comet-bridge MCP as /research and /lookup — uses
your Perplexity Pro subscription, no API tokens spent.
Usage
/factcheck <claim>
Examples:
/factcheck Postgres 18 was released in 2026/factcheck React 19 deprecates the legacy Context API/factcheck Stripe Treasury accepts EUR deposits in May 2026/factcheck Bun supports Node-native HTTP/2 in production
When to Use
- Reviewing a plan / spec / comment that contains version-sensitive claims
- Auditing AI-generated text for hallucinated facts
- Pre-flight check before relying on a "fact" in code or docs
Use /research instead when:
- The question is open-ended ("what's new in X?")
Use /lookup instead when:
- You want an answer, not a verdict on a specific assertion
Pre-flight Checks
Same as /research. Falls back to WebSearch + reasoning if comet-bridge
is unavailable, but the verdict will be lower-confidence.
Process
-
Call
mcp__comet-bridge__comet_connect. -
Call
mcp__comet-bridge__comet_askwith a structured verification prompt:Fact-check this claim and return a verdict. Claim: "<user claim>" Required output: 1. Verdict: VERIFIED | DISPUTED | UNVERIFIABLE 2. One-sentence justification 3. 2-4 supporting sources with titles and URLs 4. If DISPUTED: what the actual current state isWith
mode:search,timeout:60000. -
Parse the structured response. If the model didn't follow the format, fall back to extracting verdict heuristically (look for keywords: "true / false / partially / no evidence").
Output Format
**Claim:** <user claim>
**Verdict:** ✅ VERIFIED | ❌ DISPUTED | ❓ UNVERIFIABLE
**Justification:** <one-line explanation>
<if DISPUTED>
**Actual state:** <correct version of the fact>
</if>
**Sources:**
- [<title>](<url>)
- [<title>](<url>)
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 4d ago First seen · 118 lines · 0 tokens per session scan A c3d35e5b0ac4
factcheck is a command published in the GitHub repository sergei-aronsen/claude-code-toolkit (5 stars, last pushed 18d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 741 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other commands, from other repositories
git
Git operations with intelligent commit messages and workflow optimization.
checklist
Generate a custom checklist for the current feature based on user requirements.
clarify
Identify underspecified areas in the current feature spec by asking up to 5 highly targeted clarification questions and encoding answers back into the spec.
specify
Create or update the feature specification from a natural language feature description.
analyze
Perform a non-destructive cross-artifact consistency and quality analysis across spec.md, plan.md, and tasks.md after task generation.
converge
Assess the current codebase against the feature's spec, plan, and tasks, then append any remaining unbuilt work as new tasks to tasks.md so implement can complete it.