Write clear documentation

Documentation should be clear, precise, and self-contained while following established style conventions. When writing technical documentation:

1. Use precise language: Clearly describe how APIs work, including any restrictions or requirements.

   // Good
   // The function must be synchronous, and must not throw an error.
   fastify.setGenReqId(function (rawReq) { return 'request-id' })
      
   // Bad
   // This function can be used to set a request ID.
   fastify.setGenReqId(function (rawReq) { return 'request-id' })
   

2. Make documentation self-contained: Include all necessary context within the document itself rather than relying on external links.

   // Good
   // The `preHandler` hook allows you to specify a function that is executed before
   // routes' handler.
      
   // Bad
   // See Issue #1234 for more details on the preHandler hook.
   

3. Follow style conventions:
   • Avoid using “you” in reference documentation
   • Avoid contractions in formal documentation
   • Use proper formatting for headers, lists, and code blocks

   // Good
   // When request logging is enabled, request logs can be customized by
   // supplying a createRequestLogMessage() function.
      
   // Bad
   // You can customize your request logs by using a createRequestLogMessage() function.
   

4. Create accessible links: Provide meaningful context in link text rather than using generic phrases.

   <!-- Good -->
   [TypeScript no-floating-promises configuration](https://typescript-eslint.io/rules/no-floating-promises/)
      
   <!-- Bad -->
   Click [here](https://typescript-eslint.io/rules/no-floating-promises/) for more information.