proving-claims

proving-claims is a skill for Claude Code from FlyFission/nuclear-grade-context-engineering. It costs 65 tokens per session (1,711 once invoked), scanned A, original, MIT.

A record that links each important claim to supporting evidence, tests, evaluations, reviews, known gaps, or a narrower statement.

In plain words
What is it for?
Use it to build claim-to-evidence tables for change packets, separating facts, assumptions, unknowns, source statements, local checks, and decision authority.
Why use it?
It stops claims from going beyond what has actually been checked and makes the reasoning reproducible for another reviewer.

Skill for Claude Code

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

Part of the nuclear-grade plugin — 29 skills, 28 commands, 5 agents shipped together

Good fit Use it to build claim-to-evidence tables for change packets, separating facts, assumptions, unknowns, source statements, local checks, and decision authority.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/flyfission/nuclear-grade-context-engineering/proving-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 FlyFission/nuclear-grade-context-engineering --skill proving-claims
Clone the repo
git clone --depth 1 https://github.com/FlyFission/nuclear-grade-context-engineering

Made for: Claude Code.

Or install nuclear-grade, the plugin that ships this one along with the rest of its 29 skills, 28 commands, 5 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 proving-claims

README.md
[![agentmods](https://agentmods.dev/badge/skills/flyfission/nuclear-grade-context-engineering/proving-claims.svg)](https://agentmods.dev/skills/flyfission/nuclear-grade-context-engineering/proving-claims)
Your own site
<a href="https://agentmods.dev/skills/flyfission/nuclear-grade-context-engineering/proving-claims"><img src="https://agentmods.dev/badge/skills/flyfission/nuclear-grade-context-engineering/proving-claims.svg" alt="Measured on agentmods" height="20"></a>
Per session 65 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,711 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. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00065 $0.01711
Opus 5 $0.00032 $0.00856
Sonnet 5 $0.00013 $0.00342
Haiku 4.5 $0.00006 $0.00171

Measured 8d ago against content hash 5e503028256c, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

proving-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 8d 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.

skills/proving-claims/SKILL.md · 112 lines

How it starts

The opening of the file, as written. The whole thing — 112 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Proving Claims

Overview

Evidence should answer named claims. It should not just create a vague sense that the change is fine. This skill turns each claim into a proof you can trace. It keeps six things apart: a fact, an assumption, an unknown, a source claim (something a source says), local proof (something you checked yourself), and decision authority (who gets to decide).

Boundary: this skill builds the claim-to-evidence trace that feeds other decisions. It does not decide whether to ship (checking-release-readiness), determine whether public legal/safety wording overpromises (checking-legal-and-safety-wording), validate source lineage (checking-source-claims), or create packet files (creating-change-records).

Decision contract

  • Claim checked: every material claim is tied to evidence, a stated gap, or a deliberate deferral, no claim reaches past its evidence, and the load-bearing claim's evidence is reproducible by an independent party or independently authored — not the actor's own narration.
  • Artifact observed: basis.md, test, and review evidence -> claim-to-evidence rows with a status (pass/fail/gap/deferred/not applicable/planned) in trace.md/verification.md.
  • Decision affected: warn -- the evidence posture that later ship.md release-readiness weighs.
  • Failure class: overreaching-claim (a claim stated past its evidence, or a fail/unowned gap carried as shippable).
  • Next action: record the gap as residual risk for ship.md; a fail or unowned gap escalates to block.

When to Use

  • A change record makes claims about the code, says something about safety or security, claims release readiness, or claims a dependency can be trusted.
  • Tests pass, but reviewers cannot see which claim each test backs up.
  • Evidence gaps have to be accepted, put off, or treated as blockers.
  • The proof needs the right kind of check. The kinds are self-check, peer-check, concurrent verification (a second person checks as you go), independent verification (a separate person checks afterward), peer review, a test, or an eval.

Read the full file on GitHub · 112 lines

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. 8d ago First seen · 112 lines · 65 tokens per session scan A 5e503028256c

Subscribe to this mod's changes

proving-claims is a skill published in the GitHub repository FlyFission/nuclear-grade-context-engineering (33 stars, last pushed 2d ago), licensed MIT. It adds 65 tokens to every session and 1,711 once invoked, about $0.0003 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 2026-08-30.