skill-verify

skill-verify is a skill for Claude Code, Codex from nyldn/claude-octopus. It costs 20 tokens per session (1,257 once invoked), scanned A, a copy of skill-verification-gate, MIT.

A verification procedure for checking nontrivial changes before they are committed or shipped by running and reading the relevant commands.

In plain words
What is it for?
It is for identifying the proof command, running it, reviewing its complete output, checking failures, and reporting only what the result supports.
Why use it?
It prevents claims that code works when tests or other checks were not freshly run and confirmed.

Skill for Claude CodeCodex

Written for Claude Code and Codex: disable-model-invocation in frontmatter, but also agents/openai.yaml present. Also seen: reads .claude/ paths; mentions subagents; mentions Claude Code.

Part of the octo plugin — 70 skills, 106 commands, 10 agents, 18 hooks shipped together

Good fit It is for identifying the proof command, running it, reviewing its complete output, checking failures, and reporting only what the result supports.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/nyldn/claude-octopus/skill-verify
About the project

Claude Octopus is an orchestration project that sends research, design, and coding tasks to Claude Code and other AI model providers so their results can be compared. Developers use it for multi-model work, disagreement detection, reviews, persistent context, and an optional workflow that moves from discovery through delivery. The catalogue entries are its commands, skills, agents, instructions, hooks, plugins, and settings.

nyldn/claude-octopus · 4,058 stars · on GitHub · reddit.com

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 nyldn/claude-octopus --skill skill-verify
Clone the repo
git clone --depth 1 https://github.com/nyldn/claude-octopus

Made for: Claude Code, Codex.

Or install octo, the plugin that ships this one along with the rest of its 70 skills, 106 commands, 10 agents, 18 hooks.

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 skill-verify

README.md
[![agentmods](https://agentmods.dev/badge/skills/nyldn/claude-octopus/skill-verify/github.svg)](https://agentmods.dev/skills/nyldn/claude-octopus/skill-verify)
Your own site
<a href="https://agentmods.dev/skills/nyldn/claude-octopus/skill-verify"><img src="https://agentmods.dev/badge/skills/nyldn/claude-octopus/skill-verify/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 skill-verify

Your own site · 80×15
<a href="https://agentmods.dev/skills/nyldn/claude-octopus/skill-verify"><img src="https://agentmods.dev/badge/skills/nyldn/claude-octopus/skill-verify.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 20 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,257 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 86% copy Near-identical to another mod 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 $0.00020 $0.01257
Opus 5 $0.00010 $0.00629
Sonnet 5 $0.00004 $0.00251
Haiku 4.5 $0.00002 $0.00126

Measured 4d ago against content hash cebc077ad09f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

skill-verify 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.

Origin

This is a copy

86% identical to skill-verification-gate — 21 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

skills/skill-verify/SKILL.md · 139 lines

How it starts

The opening of the file, as written. The whole thing — 139 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Host: Codex CLI — This skill was designed for Claude Code and adapted for Codex. Cross-reference commands use installed skill names in Codex rather than /octo:* slash commands. Use the active Codex shell and subagent tools. Do not claim a provider, model, or host subagent is available until the current session exposes it. For host tool equivalents, see skills/blocks/codex-host-adapter.md.

Verification Gate

The Iron Law

If you haven't run the verification command in this turn, you cannot claim it passes.

The Gate

Before claiming any success or expressing satisfaction:

  1. IDENTIFY — What command proves this claim?
  2. RUN — Execute the full command (fresh, not cached)
  3. READ — Full output, check exit code, count failures
  4. VERIFY — Does output actually confirm the claim?
  5. ONLY THEN — State the claim WITH evidence

Skip any step = the claim is unverified.

Rationalization Table

Excuse Reality
"I ran the tests earlier this session" Earlier is not fresh. Code changed since. Run again.
"The edit was trivial, it can't break anything" Trivial edits break builds daily. The gate has no size exemption.
"The subagent reported success" Agent reports are claims, not evidence. Verify independently.
"CI will catch it anyway" CI is the safety net, not the verification. Verify before push.
"I'm confident this works" Confidence is not evidence. Run the command.
"Running the full suite is slow" Then run the targeted suite — but run something, fresh.

What Counts as Evidence

Claim Requires NOT Sufficient
Tests pass Test command output showing 0 failures Previous run, "should pass"
Build succeeds Build command exit 0 Linter passing
Bug fixed Reproduce original symptom: now passes "Code changed, should work"
Regression test works Red (fail without fix) → Green (pass with fix) Test passes once
Subagent completed task git diff shows expected changes Subagent says "done"
Requirements met Line-by-line checklist against spec Tests passing
Provider dispatch worked Output contains expected content No error ≠ success

Read the full file on GitHub · 139 lines

Files

What ships with it

1 file 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. 4d ago First seen · 139 lines · 20 tokens per session scan A cebc077ad09f

Subscribe to this mod's changes

skill-verify is a skill published in the GitHub repository nyldn/claude-octopus (4,058 stars, last pushed yesterday), licensed MIT. It adds 20 tokens to every session and 1,257 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 86% identical to skill-verification-gate, differing in 21 lines, and is treated as a copy.

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