test-file

A command that runs tests for one selected source or test file and reports each case, timing, errors, and stack traces. It can also support watch, debug, snapshot-update, and missing-test workflows.

In plain words
What is it for?
Use it to run a specific test file, find its matching tests, rerun tests while files change, debug failures, update snapshots, or identify coverage gaps.
Why use it?
It narrows test output to the code you are working on, making failures easier to inspect and fix.

Command

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 commands/cyperx84/claude-code-plugin-examples/test-file
Clone the repo
git clone --depth 1 https://github.com/cyperx84/claude-code-plugin-examples
Per session 6 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 252 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 $0.00006 $0.00252
Opus 5 $0.00003 $0.00126
Sonnet 5 $0.00001 $0.00050
Haiku 4.5 $0.00001 $0.00025

Measured yesterday against content hash e2ec4a53e877, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

test-file 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.

examples/02-intermediate/testing-plugin/commands/test-file.md · 41 lines

What it actually says

Test Specific File

Run tests for the file: $ARGUMENTS

Process:

  1. If user provides source file (e.g., @src/utils.ts):

    • Find corresponding test file
    • If no test file exists, offer to create one using /agent test-generator
  2. If user provides test file:

    • Run that specific test file
    • Show detailed output
  3. Run tests:

    • Execute with verbose output
    • Show each test case result
    • Display timing for each test
    • Show console logs if available
  4. Report results:

    • Summary for this file
    • Individual test case results
    • Any errors or failures with stack traces
    • Suggestions for fixing failures
  5. Interactive options:

    • Watch mode: Re-run on file changes
    • Debug mode: Run with debugger attached
    • Update snapshots: If snapshot tests
    • Generate missing tests: If coverage gaps

Example usage:

  • /test-file @src/utils/parser.ts
  • /test-file tests/auth.test.ts
  • /test-file UserComponent
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 · 41 lines · 6 tokens per session scan A e2ec4a53e877

Subscribe to this mod's changes

test-file is a command published in the GitHub repository cyperx84/claude-code-plugin-examples (2 stars, last pushed 10mo ago), licensed MIT. It adds 6 tokens to every session and 252 once invoked, about $0.0000 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.