verifying-claims

verifying-claims is a skill for Claude Code from isvlasov/rageatc-oss. It costs 43 tokens per session (2,093 once invoked), scanned A, original, MIT.

A fact-checking process that tests claims and judges the credibility of their sources. It uses steps for separating claims, assessing evidence, comparing sources, resolving disagreements, and expressing confidence accurately.

In plain words
What is it for?
Use it to verify factual claims, check citations, assess source quality, detect made-up information, compare evidence, and report what is certain or uncertain.
Why use it?
It reduces unsupported statements, unreliable sources, and overconfident conclusions. It also keeps a record of consulted sources and makes conflicts between credible sources visible.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the rageatc-core-oss plugin — 24 skills, 6 agents shipped together

Good fit Use it to verify factual claims, check citations, assess source quality, detect made-up information, compare evidence, and report what is certain or uncertain.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/isvlasov/rageatc-oss/verifying-claims
Install

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.

Any agent
npx skills add isvlasov/rageatc-oss --skill verifying-claims
Clone the repo
git clone --depth 1 https://github.com/isvlasov/rageatc-oss

Made for: Claude Code.

Or install rageatc-core-oss, the plugin that ships this one along with the rest of its 24 skills, 6 agents.

Wrote 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.

agentmods badge for verifying-claims

README.md
[![agentmods](https://agentmods.dev/badge/skills/isvlasov/rageatc-oss/verifying-claims/github.svg)](https://agentmods.dev/skills/isvlasov/rageatc-oss/verifying-claims)
Your own site
<a href="https://agentmods.dev/skills/isvlasov/rageatc-oss/verifying-claims"><img src="https://agentmods.dev/badge/skills/isvlasov/rageatc-oss/verifying-claims/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for verifying-claims

Your own site · 80×15
<a href="https://agentmods.dev/skills/isvlasov/rageatc-oss/verifying-claims"><img src="https://agentmods.dev/badge/skills/isvlasov/rageatc-oss/verifying-claims.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 43 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,093 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00043 $0.02093
Opus 5 $0.00022 $0.01046
Sonnet 5 $0.00009 $0.00419
Haiku 4.5 $0.00004 $0.00209

Measured 12d ago against content hash ce9b7c29e356, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

verifying-claims 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 12d 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.

plugins/rageatc-core-oss/skills/verifying-claims/SKILL.md · 145 lines

How it starts

The opening of the file, as written. The whole thing — 145 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Verifying Claims

Medium freedom: follow the phases sequentially (extract → mode → assess sources → weight → triangulate → resolve conflicts → calibrate), adapting verification depth to claim significance and risk.

Non-negotiable standards:

  • Identical verification standards for all claims (non-partisanship)
  • Document every source consulted — transparent audit trail
  • Calibrated confidence language; never present uncertain claims as certain
  • Surface disagreements between authoritative sources rather than hiding them
  • Primary sources over secondary, secondary over tertiary

Phase 1 — Extract and categorise claims

Extract discrete, verifiable assertions: statements presented as fact; names, dates, numbers, statistics, events; asserted causal relationships and predictions; factual claims embedded in interpretive passages.

Example: "The UK's ageing population, which reached 67.3 million in 2021, will strain healthcare resources" yields three claims — population 67.3 million in 2021 (factual), population ageing (factual, needs definition), will strain healthcare (interpretive/predictive).

Categorise each claim:

  • Factual/verifiable — provable with objective evidence (statistics, dates, events, findings) → full verification
  • Interpretive/analytical — facts plus judgement (causal claims, predictions, impact assessments) → verify the factual basis, assess the reasoning
  • Opinion — values, beliefs, preferences, aesthetics → do not fact-check; flag as opinion

Filter uncheckable claims and note why: future predictions, personal experiences, vague claims ("many people believe…"), hypotheticals.

Prioritise by significance (affects key conclusions or decisions), specificity, risk, and feasibility.

Phase 2 — Select verification mode

Mode A — Retrospective (sources provided). Check claims against provided documents; the standard mode for detecting extrinsic hallucinations in AI-generated content. Compare each claim systematically against the sources and flag:

Read the full file on GitHub · 145 lines

Files

What ships with it

4 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

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.

  1. 12d ago First seen · 145 lines · 43 tokens per session scan A ce9b7c29e356

Subscribe to this mod's changes

verifying-claims is a skill published in the GitHub repository isvlasov/rageatc-oss (9 stars, last pushed 1mo ago), licensed MIT. It adds 43 tokens to every session and 2,093 once invoked, about $0.0002 per session on Opus 5. 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.