Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/OutlineDriven/outline-driven-developmentnpx agentmods add skills/outlinedriven/outline-driven-development/fastify-inject-testingWrote 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/outlinedriven/outline-driven-development/fastify-inject-testing)<a href="https://agentmods.dev/skills/outlinedriven/outline-driven-development/fastify-inject-testing"><img src="https://agentmods.dev/badge/skills/outlinedriven/outline-driven-development/fastify-inject-testing/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/outlinedriven/outline-driven-development/fastify-inject-testing"><img src="https://agentmods.dev/badge/skills/outlinedriven/outline-driven-development/fastify-inject-testing.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00054 | $0.01768 |
| Opus 5 | $0.00027 | $0.00884 |
| Sonnet 5 | $0.00011 | $0.00354 |
| Haiku 4.5 | $0.00005 | $0.00177 |
Grade A, and why
fastify-inject-testing 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 5d 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 — 126 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Fastify inject testing
Contract
| Field | Bound contract |
|---|---|
| Trigger | Testing Fastify applications without network sockets: auth, validation errors, uploads, streams, plugins, hooks. |
| Authority | Reversible local: write only test files under the project test tree and run node:test suites. Roll back by deleting the added test files and reverting test-only config; never mutate application source, credentials, or remote state. |
| Side effect | Writes test files; runs node:test suites. |
| Done | Integration tests exercise routes via inject() with no listener, covering auth, validation failure, and at least one stream/upload path, passing in parallel. |
Inputs
- A Fastify application factory (e.g.
buildApp()orbuildTestApp(options)) that returns a readyFastifyInstancewithout callinglisten(). Required. - Route definitions under test (path, method, schema, auth). Required.
- Optional: a test database URL (
TEST_DATABASE_URL) or mocked dependency factories for isolation. - Optional: fixture files for upload tests (e.g.
./test/fixtures/test.pdf).
Procedure
- Build a reusable test app factory that constructs
Fastify({ logger: false, ...options }), registers the real plugins and routes, callsawait app.ready(), and returns{ app, inject: app.inject.bind(app) }. Never callapp.listen();inject()simulates HTTP without a network socket.
import Fastify from 'fastify';
import type { FastifyInstance } from 'fastify';
export async function buildTestApp(options = {}): Promise<{
app: FastifyInstance;
inject: FastifyInstance['inject'];
}> {
const app = Fastify({ logger: false, ...options });
app.register(import('../src/plugins/database.js'), {
connectionString: process.env.TEST_DATABASE_URL,
});
app.register(import('../src/routes/index.js'));
await app.ready();
return { app, inject: app.inject.bind(app) };
}
Done when: the factory returns { app, inject } without calling listen().
- In each
describeblock, create a fresh app instance inbeforeand close it inafterso suites are isolated and can run in parallel.
What ships with it
1 file 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.
- 5d ago First seen · 126 lines · 54 tokens per session scan A b79dc9152601
fastify-inject-testing is a skill published in the GitHub repository OutlineDriven/outline-driven-development (52 stars, last pushed 4d ago), licensed Apache-2.0. It adds 54 tokens to every session and 1,768 once invoked, about $0.0003 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.
Other skills, from other repositories
server-side-calls
Call tRPC procedures directly from server code using t.createCallerFactory() and router.createCaller(context) for integration testing, internal server logic, and custom API endpoints. Catch TRPCError and extract HTTP status with getHTTPStatusCodeFromError(). Error handling via onError option.
voiden
Create and edit Voiden .void files for API testing. Covers the .void file format and all enabled extension block types.
csharp-dotnet
Use when writing, reviewing, testing, or shipping C# / .NET code — ASP.NET Core APIs (minimal APIs vs controllers), EF Core data access, async correctness, solution layout in .cs/.csproj/.sln. NOT a Java/Spring backend (that is spring-boot), NOT a Node/TypeScript backend (that is nestjs), NOT framework-neutral REST…
1c-xdto-validate
A checker for XDTO packages in 1C:Enterprise. XDTO describes the structure and data types used when 1C exchanges data with external systems.
verification-before-completion
Use when a task, feature, or fix is called done, complete, finished, or fixed, or before a commit, PR, or next task. Not for fact-checking: use verify-both-ways. Not for measuring: use verify-this.
backend-dev-guidelines
Backend development guidelines for Node.js/Express/TypeScript applications. Layered architecture (Routes → Controllers → Services → Repositories), error handling, validation, middleware patterns, database access, and testing. Use when creating routes, endpoints, APIs, controllers, services, repositories, middleware…