valid-skill

Guidance for using skills correctly.

In plain words
What is it for?
Use it when testing valid skill usage.
Why use it?
It helps check whether a skill is being parsed and used as intended.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/probelabs/probe/valid-skill
Any agent
npx skills add probelabs/probe --skill valid-skill
Clone the repo
git clone --depth 1 https://github.com/probelabs/probe

Made for: Claude Code, Codex.

Per session 11 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 25 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00011 $0.00025
Opus 5 $0.00005 $0.00013
Sonnet 5 $0.00002 $0.00005
Haiku 4.5 $0.00001 $0.00003

Measured 2d ago against content hash 5c62a748d45f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

valid-skill 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 2d 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.

test_data/skills/.claude/skills/valid-skill/SKILL.md · 7 lines

What it actually says

Use this skill to test valid parsing.

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. 2d ago First seen · 7 lines · 11 tokens per session scan A 5c62a748d45f

Subscribe to this mod's changes

valid-skill is a skill published in the GitHub repository probelabs/probe (695 stars, last pushed 2d ago), licensed Apache-2.0. It adds 11 tokens to every session and 25 once invoked, about $0.0001 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.

Related

Other skills, from other repositories

vex

Reference for the vex code-search CLI — symbol search, usages (text + scope-bound --strict), structural AST patterns, call graph, semantic search, and content grep. Activates when picking the right vex subcommand, recalling filter flags, or checking the cross-file binder coverage matrix. Use whenever you'd otherwise…

tenatarika/vex · 81 tokens

search

Deep research powered by Exa. Use for lead generation, literature reviews, deep dives, competitive analysis, or any query where one search falls short, including phrases like 'research this', 'find everything about', 'find me all', or 'deep dive on'.

exa-labs/exa-mcp-server · 55 tokens

wakaru

Turn minified, bundled, or transpiled JavaScript back into readable modules. Use when you encounter unreadable production JS — a webpack/esbuild/Metro/Rollup bundle, a minified vendor script, Babel/TypeScript/SWC-transpiled output, or a single mangled .js file — and need to read, audit, debug it, or recover a…

pionxzh/wakaru · 99 tokens

x-ray

Deep codebase exploration using semantic search and relationship mapping. Use when you need to understand the current codebase.

bartolli/codanna · 25 tokens

deep-research

Use when a question requires deep investigation using online information or web search, broad source-backed research, comparison of multiple perspectives, or synthesis beyond a quick lookup.

7df-lab/devo · 35 tokens

windows-compat

Audit and harden this Rust repo (code-graph-mcp) for Windows correctness: path-spelling drift between producers, the 32,767-char command-line cap, index-key mismatches, and path predicates that assume one ecosystem's layout. Use whenever touching code that builds, compares, prints, or stores a filesystem path; that…

sdsrss/code-graph-mcp · 165 tokens