testing-rules

testing-rules is a skill for Claude Code from rocky2431/ultra-builder-pro. It costs 10 tokens per session (425 once invoked), scanned A, original, MIT.

A set of testing rules based on TDD, or test-driven development, where tests are written before the code and guide its implementation. It defines which tests and test doubles to use across pure logic, databases, services, and external APIs.

In plain words
What is it for?
Use it to structure new code around the red-green-refactor cycle, choose unit or integration tests, test real database behavior with Testcontainers, and enforce coverage targets.
Why use it?
It reduces tests that only imitate production behavior and can miss real database or service integration problems.

Skill for Claude Code

Written for Claude Code: user-invocable in frontmatter.

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/rocky2431/ultra-builder-pro/testing-rules
Any agent
npx skills add rocky2431/ultra-builder-pro --skill testing-rules
Clone the repo
git clone --depth 1 https://github.com/rocky2431/ultra-builder-pro

Made for: Claude Code.

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 testing-rules

README.md
[![agentmods](https://agentmods.dev/badge/skills/rocky2431/ultra-builder-pro/testing-rules.svg)](https://agentmods.dev/skills/rocky2431/ultra-builder-pro/testing-rules)
Your own site
<a href="https://agentmods.dev/skills/rocky2431/ultra-builder-pro/testing-rules"><img src="https://agentmods.dev/badge/skills/rocky2431/ultra-builder-pro/testing-rules.svg" alt="Measured on agentmods" height="20"></a>
Per session 10 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 425 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 5.1 $0.00010 $0.00425
Opus 5 $0.00005 $0.00212
Sonnet 5 $0.00002 $0.00085
Haiku 4.5 $0.00001 $0.00042

Measured 6d ago against content hash b042a1920f0c, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

testing-rules 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 6d 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/testing-rules/SKILL.md · 57 lines

What it actually says

Testing Rules

These rules are mandatory for all test-related work.

TDD Workflow

RED → GREEN → REFACTOR (all new code).

Test Strategy

Layer Test Type Mock Strategy
Functional Core Unit Test No mocks needed (pure input→output)
Imperative Shell Integration Testcontainers (real DB/services)
External APIs Test Double With // Test Double rationale: [reason]

Forbidden Patterns

These patterns are never acceptable:

Pattern Why Forbidden Alternative
jest.fn() for Repository/Service/Domain Invalid test — doesn't prove production works Testcontainers
class InMemoryRepository Diverges from real DB behavior Real DB container
class MockXxx / class FakeXxx Hides integration issues Direct instantiation or Testcontainers
jest.mock('../services/X') Skips real collaboration Test real collaboration
it.skip('...database...') "Too slow" is not valid Testcontainers are fast enough

Coverage Requirements

  • 80% overall minimum
  • 100% Functional Core (pure logic must be fully tested)
  • Critical paths for Imperative Shell

Dev/Prod Parity

Tests must use real dependencies:

  • Real database via Testcontainers (not in-memory substitutes)
  • Config via environment variables
  • Mock tests passing ≠ production working

Detection Checklist

When analyzing test files, flag:

  1. Any jest.fn() usage on Repository, Service, or Domain classes
  2. Any InMemory* or Mock* or Fake* class definitions
  3. Any jest.mock() calls on internal modules
  4. Any skipped tests with database/slow excuses
  5. Missing error case coverage
  6. Missing edge case coverage
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. 6d ago First seen · 57 lines · 10 tokens per session scan A b042a1920f0c

Subscribe to this mod's changes

testing-rules is a skill published in the GitHub repository rocky2431/ultra-builder-pro (11 stars, last pushed 1mo ago), licensed MIT. It adds 10 tokens to every session and 425 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.