opensession: Skill for Claude Code

.agents/skills/pstack-suite/skills/create-verification-skill/SKILL.md

create-verification-skill is a skill for Claude Code, Codex from tellahq/opensession. It costs 65 tokens per session (1,347 once invoked), scanned A, a copy of create-verification-skill, MIT.

A workflow for creating a project-local skill that launches and tests an application the way a user would, producing evidence that it works.

In plain words
What is it for?
Use it to inspect a repository, find its startup and interaction methods, and generate a verification skill for its main application surface.
Why use it?
Projects without scripted checks make it difficult for an agent to prove that UI, command-line, service, or other user-facing behavior still works.

Skill for Claude CodeCodex

Written for Claude Code: disable-model-invocation in frontmatter. Also seen: reads .claude/ paths; installed under .agents/ (shared by several agents).

This is tellahq/opensession's own configuration. It tells Claude Code and Codex how to work on opensession itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything opensession configures →

Reuse

Borrowing it

Nothing to install: this file belongs to tellahq/opensession. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/tellahq/opensession/main/.agents/skills/pstack-suite/skills/create-verification-skill/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/tellahq/opensession

Made for: Claude Code, Codex.

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 create-verification-skill

README.md
[![agentmods](https://agentmods.dev/badge/skills/tellahq/opensession/create-verification-skill/github.svg)](https://agentmods.dev/skills/tellahq/opensession/create-verification-skill)
Your own site
<a href="https://agentmods.dev/skills/tellahq/opensession/create-verification-skill"><img src="https://agentmods.dev/badge/skills/tellahq/opensession/create-verification-skill/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 create-verification-skill

Your own site · 80×15
<a href="https://agentmods.dev/skills/tellahq/opensession/create-verification-skill"><img src="https://agentmods.dev/badge/skills/tellahq/opensession/create-verification-skill.svg" alt="Reviewed on agentmods" width="80" 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 1,347 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 2 findings, up to high

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • high Agent Snooping · line 25
    Skill reads from agent configuration directories (.claude/, .codex/, .gemini/). These directories may contain API keys, personal settings, and other credentials that the skill has no legitimate need to access.
    Fix: Remove all code or instructions that access agent configuration directories (.claude/, .codex/, .gemini/). If configuration values are needed, pass them explicitly as parameters or environment variabl
  • medium Agent Snooping · line 25
    Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.
    Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
How audits are shown
Origin 95% 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 $0.00065 $0.01347
Opus 5.5 $0.00026 $0.00539
Sonnet 5.5 $0.00013 $0.00269
Haiku 4.5 $0.00006 $0.00135

Measured 1mo ago against content hash e267f8c35afd, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

create-verification-skill scanned grade A with 1 finding 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 1mo 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

- **Drive:** how can an agent interact with it programmatically? Existing harnesses first — Playwright/Cypress specs, expect scripts, PTY helpers, curl-able endpoints, a debug port. Only then pick a generic recipe: brows
Origin

This is a copy

95% identical to create-verification-skill — 30 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.

.agents/skills/pstack-suite/skills/create-verification-skill/SKILL.md · 45 lines

How it starts

The opening of the file, as written. The whole thing — 45 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Create a verification skill

Every serious project needs a scripted way to drive the real app and prove behavior: launch it, exercise a feature the way a user would, and capture evidence. This skill generates that as a project-local Open Session skill (.agents/skills/verify-<app>/) tailored to the repo. You write the generator's output for the next agent, not for a human: it will be read cold, mid-task, by an agent that has never seen the app.

1. Interview the repo, not the user

Answer these from the codebase and only ask the user what you cannot observe:

  • Surface: what does a user actually touch? A web UI, a CLI/TUI, a desktop app, an API, a mobile app, a library? A repo can have several; pick the primary one and note the rest.
  • Run: how does the app start locally? Prefer the repo's own documented dev command (package scripts, Makefile, README quickstart). Note ports, env vars, seed data, auth.
  • Drive: how can an agent interact with it programmatically? Existing harnesses first — Playwright/Cypress specs, expect scripts, PTY helpers, curl-able endpoints, a debug port. Only then pick a generic recipe: browser/CDP for web and Electron, a tmux/PTY harness for CLI/TUI, plain HTTP for services.
  • Observe: what evidence can be captured? Screenshots, terminal transcripts, response bodies, logs, exit codes, DB state.
  • Isolate: can two instances run side by side (ports, data dirs, profiles)? If not, say so in the generated skill: refusing to double-drive a shared instance beats corrupting the user's session.

If the checkout doesn't build or start as-is, fix that first (or report it precisely) before generating; a skill written against a broken base teaches wrong steps. When an irrelevant missing asset blocks startup (a static dir the API never serves, a sample config), the generated skill may create it, clearly marked as verification scaffolding, and remove it in cleanup.

2. Generate the skill

Write .agents/skills/verify-<app>/SKILL.md with YAML frontmatter (name: verify-<app> and a description that names the app, the surface, and when to reach for it — without frontmatter the skill never registers) and these sections, each grounded in what the interview actually found (no placeholders left). Open Session loads project skills from .agents/skills/ and .claude/skills/; use .agents/skills/ unless the repository already standardizes on .claude/skills/:

Read the full file on GitHub · 45 lines

Files

What ships with it

3 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. 1mo ago First seen · 45 lines · 65 tokens per session scan A e267f8c35afd

Subscribe to this mod's changes

create-verification-skill is a skill published in the GitHub repository tellahq/opensession (399 stars, last pushed today), licensed MIT. It adds 65 tokens to every session and 1,347 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). It is 95% identical to create-verification-skill, differing in 30 lines, and is treated as a copy.

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