tests

name

tests

description

Add or normalize unit testing for a Blueprint project. Detects the stack, reuses an existing test runner when present, or installs the stack-native unit test runner when missing, then adds one small example test, updates AGENTS.md commands, runs build and tests, and reports the diff. Use when the user runs /tests, invokes $tests, asks to add unit tests, set up unit testing, configure tests, or make tests part of the Blueprint workflow.

tests - add unit testing to the project

Where this sits in the workflow:

any time  ->  [tests]  ->  test command in AGENTS.md  ->  /feature + /implement use it
              (setup)     (the opt-in testing gate)      (logic steps get tests)

Testing is optional in the Blueprint until the project declares a real test command in AGENTS.md. This skill is the explicit setup path. It adds or normalizes unit testing only; browser automation and end-to-end testing are separate setup work.

Input

No argument is required. If the user names a runner or stack preference, treat it as a preference and verify it against the project files.

Step 1 - inspect the project

Read enough files to identify the real setup:

• AGENTS.md Commands section
• package or language manifest (package.json, pyproject.toml, go.mod, Cargo.toml, and similar)
• existing test config (vitest.config.*, jest.config.*, pytest.ini, phpunit.xml, language-native config, and similar)
• existing test files
• package manager lockfile
• blueprint/context/coding-standards.md

Do not assume Next.js. Detect the stack from files.

Step 2 - choose the smallest test setup

Prefer the existing runner if one is already present. If none exists, choose the stack-native unit test runner:

• TypeScript or JavaScript app: Vitest by default, unless the project already clearly uses Jest or another runner.
• Python: pytest.
• Go: built-in go test.
• Rust: built-in cargo test.
• Ruby: the runner already implied by the project, or Minitest when nothing else is present.
• PHP: PHPUnit when the project is Composer-based.

If the stack is unclear, stop and ask what runner to use instead of guessing.

Keep the setup minimal. Do not add coverage, browser testing, CI, snapshots, mock-service layers, or a large test architecture unless the user explicitly asks.

Step 3 - make the setup changes

Apply the smallest practical diff:

1. Add missing test dependencies or config.
2. Add or normalize package/script commands.
3. Add one small example test for real project logic if a suitable function exists; otherwise add a tiny helper and test that proves the runner works.
4. Update the Commands section of AGENTS.md with the real test command and, when available, the test watch command.
5. Update blueprint/context/coding-standards.md only if the project needs a stack-specific testing note different from the default.

Do not write a broad test suite for existing app code. This skill proves the testing path and turns on the gate; feature work adds focused tests later.

If adding dependencies requires network access, ask for the needed install command through the current tool's approval flow. Use the project's package manager.

Step 4 - verify

Run the relevant commands from AGENTS.md:

• the test command
• the build command, when one exists
• lint or typecheck only if they are already standard commands and the diff touches config or types that should satisfy them

An empty suite must not be treated as a pass. If the runner reports no tests, add or fix the example test.

Step 5 - report

Stop with a concise report:

• runner chosen or reused
• commands added or updated
• example test added
• verification commands run and whether they passed
• any follow-up the user should consider

Show the diff summary. Do not commit, merge, push, or start product feature work.

Rules

• Unit testing only. Do not set up Playwright, Cypress, browser E2E, CI, or coverage unless the user explicitly asks.
• Reuse existing project conventions before adding new tools.
• Keep the first test boring and small. It exists to prove the workflow.
• Once AGENTS.md has a test command, later /feature and /implement runs treat tests as the gate for logic-bearing changes.
• Do not hide install or verification failures. Report exactly what failed and what to fix next.

Formatting

Format the output to match the project's conventions in blueprint/context/ai-interaction.md: concise, scannable markdown, with lists for enumerations and tables for matrices rather than dense paragraphs.