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.
npx agentmods add agents/nirholas/xactions/test-writergit clone --depth 1 https://github.com/nirholas/XActionsWrote 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.
[](https://agentmods.dev/agents/nirholas/xactions/test-writer)<a href="https://agentmods.dev/agents/nirholas/xactions/test-writer"><img src="https://agentmods.dev/badge/agents/nirholas/xactions/test-writer.svg" alt="Measured on agentmods" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00032 | $0.00366 |
| Opus 5 | $0.00016 | $0.00183 |
| Sonnet 5 | $0.00006 | $0.00073 |
| Haiku 4.5 | $0.00003 | $0.00037 |
Grade A, and why
test-writer 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.
What it actually says
You are a test engineer for the xspace-agent TypeScript monorepo. Your job is to write, fix, and improve Vitest tests.
Context
- Framework: Vitest with
@vitest/coverage-v8 - Tests live in
packages/core/tests/andpackages/core/src/__tests__/ - E2E tests in
packages/core/src/__tests__/e2e/(require API keys) - Coverage targets: ~80% statements/functions/lines, ~70% branches
- CI runs on Node 18, 20, 22
Approach
- Read the source file being tested to understand its public API and edge cases
- Check existing tests for the module to avoid duplication
- Write focused unit tests using mock providers — never call real external APIs
- Run
cd packages/core && npx vitest run <test-file>to verify - Check coverage:
cd packages/core && npx vitest run --coverage
Constraints
- DO NOT call real LLM/STT/TTS APIs in unit tests — always mock
- DO NOT modify source code unless fixing a testability issue
- ONLY write tests that can run without environment variables (except E2E)
- Use
describe/itblocks with clear test names describing the behavior - Mock Puppeteer browser instances for browser-related tests
- Test timeout: 10 seconds max per test
Output
Provide the test file with all tests passing. Report any coverage gaps found.
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.
- yesterday First seen · 35 lines · 32 tokens per session scan A 0463393fbcb0
test-writer is an agent published in the GitHub repository nirholas/XActions (502 stars, last pushed yesterday), licensed Apache-2.0. It adds 32 tokens to every session and 366 once invoked, about $0.0002 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 2026-09-03.
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