test-first

test-first is a skill for Claude Code from orkait/hyperstack. It costs 28 tokens per session (1,121 once invoked), scanned A, original, no licence file.

A test-first development skill for features, bug fixes, and behaviour changes. Test-first development means writing a test before writing the code that makes it pass.

In plain words
What is it for?
Use it before implementing a feature, fixing a bug, or changing existing behaviour.
Why use it?
It helps establish the expected behaviour before implementation and prevents coding first without a check for the intended result.

Skill for Claude Code

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

Part of the hyperstack plugin — 29 skills, 1 hook, 1 MCP server shipped together

Good fit Use it before implementing a feature, fixing a bug, or changing existing behaviour.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/orkait/hyperstack/test-first
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 orkait/hyperstack --skill test-first
Clone the repo
git clone --depth 1 https://github.com/orkait/hyperstack

Made for: Claude Code.

Or install hyperstack, the plugin that ships this one along with the rest of its 29 skills, 1 hook, 1 MCP server.

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 test-first

README.md
[![agentmods](https://agentmods.dev/badge/skills/orkait/hyperstack/test-first/github.svg)](https://agentmods.dev/skills/orkait/hyperstack/test-first)
Your own site
<a href="https://agentmods.dev/skills/orkait/hyperstack/test-first"><img src="https://agentmods.dev/badge/skills/orkait/hyperstack/test-first/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 test-first

Your own site · 80×15
<a href="https://agentmods.dev/skills/orkait/hyperstack/test-first"><img src="https://agentmods.dev/badge/skills/orkait/hyperstack/test-first.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 28 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,121 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 unknown 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 $0.00028 $0.01121
Opus 5.5 $0.00011 $0.00448
Sonnet 5.5 $0.00006 $0.00224
Haiku 4.5 $0.00003 $0.00112

Measured 1mo ago against content hash 66772ebd7187, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

test-first 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 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.

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/test-first/SKILL.md · 150 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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 Changed 66772ebd7187
  2. 1mo ago First seen · 150 lines · 28 tokens per session scan A 6f80640ba71d

Subscribe to this mod's changes

test-first is a skill published in the GitHub repository orkait/hyperstack (1 stars, last pushed 1mo ago), with no licence file. It adds 28 tokens to every session and 1,121 once invoked, about $0.0001 per session on Opus 5.5. 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.

Related

Other skills, from other repositories

adversarial-reviewer

Stress-test a code change for concrete correctness defects, unsafe assumptions, and failure modes. Use when the user explicitly asks for an adversarial review, a deep bug hunt, or to tear a change apart, or to check your own change before submitting it. Do not use for ordinary review, style feedback, or general…

emdash-cms/emdash · 72 tokens

om-troubleshooter

Diagnose and fix standalone Open Mercato bugs across scope, commands, locking, fields, generated registries, UI hydration, cache/search, bootstraps, queues, and providers. Use for "fix bug", "why does this fail", "regression", "debug", "napraw błąd", or a failing test.

open-mercato/open-mercato · 73 tokens

fixing-flaky-tests

Guides an agent through reproducing, root-causing, fixing, and validating flaky tests in the PostHog monorepo. Use when a test fails intermittently in CI but passes on rerun or locally, when hogli ci:insights or the debugging-ci-failures skill classifies a failure as a flaky test, when given a GitHub Actions URL for a…

PostHog/posthog · 220 tokens

test-electron-app

Drive the real running PostHog Electron app (live tRPC, workspace-server, real data) over CDP with agent-browser. Connect to the running app on port 9222, test desktop changes against a local Django stack, snapshot the accessibility tree, inspect network requests, and screenshot only when explicitly asked. Use when…

PostHog/posthog · 112 tokens

extending-hobby-smoke-tests

Design, extend, review, or debug PostHog Hobby end-to-end smoke tests in bin/hobby-ci.py and .github/workflows/ci-hobby.yml. Use when adding an ingestion round trip, deciding whether a product belongs in Hobby CI, changing the CI Hobby service topology or API-key scopes, or diagnosing a smoke test that captures data…

PostHog/posthog · 83 tokens

extending-personhog-test-harness

When and how to add scenarios, chaos events, and invariants to the personhog e2e test harness (rust/personhog-test-harness). Use after fixing a bug or regression in the personhog leader path (leader, router, writer, replica, coordination protocol) so the fix gets a permanent regression scenario; when adding a new…

PostHog/posthog · 134 tokens