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 skills add bartstc/vite-ts-react-template --skill test-building-blocksgit clone --depth 1 https://github.com/bartstc/vite-ts-react-templateWrote 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/skills/bartstc/vite-ts-react-template/test-building-blocks)<a href="https://agentmods.dev/skills/bartstc/vite-ts-react-template/test-building-blocks"><img src="https://agentmods.dev/badge/skills/bartstc/vite-ts-react-template/test-building-blocks/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/bartstc/vite-ts-react-template/test-building-blocks"><img src="https://agentmods.dev/badge/skills/bartstc/vite-ts-react-template/test-building-blocks.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 2 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Prompt Injection · line 49 Large whitespace padding was detected (a block of blank lines or a long run of spaces). This can push injected instructions below or to the right of the visible area so a human reviewer never sees them while the agent still reads them. Manual review of the hidden content is recommended.Fix: Remove the large whitespace padding (blank-line blocks or long space runs) and review any content hidden below or to the right of it. Keep skill files compact and reviewable so no instructions can be
- medium Prompt Injection · line 57 Large whitespace padding was detected (a block of blank lines or a long run of spaces). This can push injected instructions below or to the right of the visible area so a human reviewer never sees them while the agent still reads them. Manual review of the hidden content is recommended.Fix: Remove the large whitespace padding (blank-line blocks or long space runs) and review any content hidden below or to the right of it. Keep skill files compact and reviewable so no instructions can be
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 5.1 | $0.00000 | $0.01235 |
| Opus 5.5 | $0.00000 | $0.00494 |
| Sonnet 5.5 | $0.00000 | $0.00247 |
| Haiku 4.5 | $0.00000 | $0.00123 |
Grade A, and why
test-building-blocks 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 82 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Test Building Blocks
Typed catalog of test-related building blocks used in this project. Each block has a fixed name, layer, composition rules, and canonical example.
How to Use
Read the rule file for each block you are about to implement. The summaries below are for routing — the rule files contain the full pattern.
Typical flow:
- Read this file to route to the right block.
- Read
rules/{block-name}.mdfor the full pattern and canonical example. - Read the implementation code (component, hook, module) you are testing.
- Write the test following the rule file's constraints.
Testing Philosophy
The project's testing philosophy allocates verification across three layers:
- Storybook play-function tests are the primary verification layer for feature behavior. Focus on happy paths and the main user-observable states. Anything user-facing — components composing hooks, stores, providers — is verified here.
- Vitest hook tests (
renderHook) cover custom hooks that need dedicated verification — edge cases, error paths, loading states, and hooks with logic not tied to a single component. Use independently ofcomponent-story-test; the two do not need to cover the same ground. - Vitest unit tests are reserved for non-hook mechanics: mappers, transformers, value objects, selectors, and other pure logic.
- No tests for fixtures, MSW handlers, or trivial glue — these are support infrastructure, not the thing being verified.
Coverage is behavior-covered, not file-mapped. Every user-observable state has a story or a hook-test scenario; not every file has a test.
Mocking Boundary
Mock at the network boundary, not the module boundary. MSW is the default for anything HTTP-backed. Do not mock lib/api/ exports, React Query, or Zustand stores — let the real code run and intercept at the wire.
Module-level mocking (vi.mock, vi.stubGlobal) is reserved for:
- Non-determinism sources:
Date.now,crypto.randomUUID,Math.random, timers. - Write-only side-effect sinks: analytics, logging, toasts — centralized as project-owned spies in
test-lib/. - Pure utilities when unit-testing their direct caller.
- XState actors/actions via
machine.provide({ actors, actions }).
What ships with it
7 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 1mo ago First seen · 82 lines · 0 tokens per session scan A c86d48cbda83
test-building-blocks is a skill published in the GitHub repository bartstc/vite-ts-react-template (123 stars, last pushed 12d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,235 tokens. 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.
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