testing-rules

A set of testing instructions for software projects that use Docker, a tool for running applications in isolated containers.

In plain words
What is it for?
Running unit, API, end-to-end, browser, performance, SDK, and client tests; rebuilding test containers, applying migrations, and debugging test failures.
Why use it?
It gives coding agents a consistent way to run tests in the right containers instead of on the developer’s computer, while checking common setup problems first.

Cursor rule

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 rules/dobryakov/cursor-rules/testing-rules
Clone the repo
git clone --depth 1 https://github.com/dobryakov/cursor-rules
Per session 287 This file is loaded in full into every session.
When invoked 287 The same file — it is already loaded in full.
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 $0.00287 $0.00287
Opus 5 $0.00143 $0.00143
Sonnet 5 $0.00057 $0.00057
Haiku 4.5 $0.00029 $0.00029

Measured yesterday against content hash 2613318e5415, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 yesterday.

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.

en/rules/testing-rules.mdc · 19 lines

What it actually says

Testing Strategy

  • Do not run tests on the host! Run tests inside docker containers.
  • After completing each task, run the relevant automated tests, including browser and performance tests whenever possible.
  • Choose the environment according to the type of tests: put unit tests inside the service container, put API and e2e tests in separate test containers. Make sure to add the tests dir to the image.
  • Connect test containers to the main docker-compose.yml.
  • Before starting tests, check if the test container needs to be rebuilt and migrations applied.
  • If the project includes an SDK or software clients, they must be covered by separate tests.
  • If using Playwright, make sure you have browsers installed to the test container.
  • If using Playwright, consider to use proper "FROM" image (for example, debian-based node.js image) in the Dockerfile before building test container.
  • When calling docker compose logs with tail, use proper syntax: docker compose logs --tail 10 <container name>.
  • It is recommended to include tests dir to the container as volumes in docker-compose.yml to re-run the tests without re-building the image.
  • Always try first to debug the errors/warnings by running the corresponding tests. Add the tests if its needed.
  • After fixing every bug, write tests to cover it, and run them.
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. yesterday First seen · 19 lines · 287 tokens per session scan A 2613318e5415

Subscribe to this mod's changes

testing-rules is a cursor rule published in the GitHub repository dobryakov/cursor-rules (2 stars, last pushed 2mo ago), licensed MIT. It adds 287 tokens to every session, about $0.0014 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 2026-08-31.