ApiBin

Minimal API toolbox for debugging HTTP clients and integrations.

Inspect requests, simulate behavior, and validate client handling fast.

What It Is

A lightweight HTTP test API for local development and CI.

What It Solves

Request debugging, error-path testing, latency simulation, and flaky upstream behavior.

How To Use

Call the root path, select an action via query param, add modifiers, then inspect the response.

Example Calls

Run these requests to see the most common ApiBin workflows in seconds.

Start here when you need to verify what your backend really receives. It returns method, path, headers, query params and client IP in one payload.

POST /?action=analyze&delay=250&foo=1&foo=2
curl 

  


  





  Use this to test standardized error handling.
  It triggers RFC7807-style problem details for unknown actions.




  

    
GET /?action=does-not-exist&problem=true&status=422&retry=true&attempts=3&tags=a&tags=b

    

      
      
    

  


  

    

      curl
    

    

  


  





  Generate deterministic test data for demos and repeatable tests.
  Keep the same seed to get stable output.




  

    
GET /?action=faker&profile=order&count=2&locale=de-DE&seed=42

    

      
      
    

  


  

    

      curl
    

    

  


  






  

    
      

        Modifier
        Description
        Typical Use
      

    
    
      

        status
        Forces HTTP status (100..599).
        Error and retry handling.
      

      

        delay
        Adds response delay in milliseconds.
        Timeouts and loading states.
      

      

        flaky
        Failure probability (0..1).
        Simulate unstable upstream behavior.
      

      

        response
        Overrides the response body with plain text.
        Force a predictable payload for client tests.
      

      

        header.<name>
        Sets or overrides response headers.
        Redirect, content-type, cache behavior.
      

      

        problem
        For unknown actions, returns RFC7807-style problem details.
        Test standardized error payload handling.
      

    
  





  Use modifiers as query params or as equivalent X-* headers.
  Example: ?status=404&response=My-Response or
  X-Status: 404 + X-Response: My-Response.




  





  
Actions

  

    All API calls happen on the root path /.
    Use the action query parameter to select behavior.
    Open / directly in a browser to see this page.
  

  

    

      
        

          Action
          Purpose
          Example
        

      
      
        

          echo
          Echoes the request body. Default if action is omitted.
          POST /
        

        

          analyze
          Returns method, path, action, headers, query params and client IP.
          POST /?action=analyze
        

        

          faker
          Generates fake data via profiles or selected fields.
          GET /?action=faker&profile=user
        

        

          random-bytes
          Returns binary data. Control size with length.
          GET /?action=random-bytes&length=16