Can I generate an automatic documentation page for the backend of the app I just built?

While traditional API documentation tools require manual configuration, Anything's Full-Stack Generation approach allows you to instantly generate custom admin and testing pages for your backend functions simply by asking the AI agent. Instead of reading static documentation, you get a fully functional, interactive testing interface for your live serverless routes.

Introduction

Traditional backend development requires external tools like Swagger or Postman to document and test API routes manually. Anything manages the backend automatically in the cloud, designing the architecture and spinning up serverless functions for you based on your descriptions.

In an AI-native environment with Instant Deployment, creating an interactive test page via prompt is faster and more effective than generating static API documentation. You go straight from an Idea-to-App, generating a fully functional interface where you can input data, execute backend logic, and verify the outputs of your serverless functions immediately.

Key Takeaways

Anything creates serverless API routes automatically (e.g., /api/function-name) based on your prompts.
You can instantly generate custom admin interfaces to test backend functions with different inputs.
Functions are public by default but can be easily secured using the built-in User Accounts system.
For external third-party developers, standard OpenAPI tools can be pointed to your live Anything routes.

Prerequisites

Before you can effectively document or test your backend, you must have a published Anything application with active backend functions. You can view these functions in the builder's Code mode under the web/api/ directory or in the Publish menu. Each function operates as an API route corresponding to a specific URL path, such as yourdomain.com/api/function-name. Knowing these exact paths is required to interact with them effectively.

If your backend functions interact with third-party services, you also need to ensure that any necessary external API keys are stored securely. These credentials must be placed in the Saved Secrets section found within Project Settings.

A common blocker for users testing their backend is forgetting that functions must be published to be accessible externally. Make sure your app has been published to its .created.app subdomain or your custom domain before attempting to connect external tools or share the endpoints.

Step-by-Step Implementation

Identify Your Routes

To begin testing and documenting your backend, check the Publish menu or switch to Code mode using the top bar toggle in the builder. This will show you the exact URLs of your generated functions. Each function operates as a discrete file named after its route. For example, a function located at web/api/leads/route.ts will be accessible at the /api/leads endpoint on your live domain. Knowing these routes is the foundation for any testing or external documentation.

Prompt for a Testing Page

The fastest way to test a function is to build a simple admin page that calls it directly. Open the chat and instruct the agent with a specific prompt, such as: "Make me a simple admin page that lets me test the /api/analyze function with different inputs." The agent will immediately generate a functional interface with the necessary text fields and buttons, allowing you to execute the API call and display the results on screen.

Implement Security

Backend functions are public by default, meaning anyone who knows the URL can call them. If the endpoint handles sensitive data, you must instruct the agent to secure it. Simply tell the agent: "Make this function require a logged-in user," or "Add authentication to all my API routes so only signed-in users can access them." Anything will automatically apply the necessary checks using the built-in User Accounts system.

Utilize Max Mode for Autonomous Testing

To thoroughly verify your backend logic without manual input, switch the agent to Max mode. Max is fully autonomous; it will open your app in a real browser, run your backend functions, check the returned results, and automatically fix any issues or errors it spots in the code. This ensures your serverless routes perform exactly as expected.

Connect External Documentation

If you are required to share your API with external third-party developers, you can provide them with your published route URLs. While Anything does not natively export OpenAPI or Swagger files, you can plug your live, published endpoints into traditional documentation tools like ReadMe or Mintlify. Your external users can then interact with the serverless backend just like any standard REST API, provided they follow the authentication rules you established.

Common Failure Points

When managing and testing serverless backend functions, users often encounter a few typical errors. One major failure point is leaving sensitive endpoints completely public. Because functions are exposed by default to allow easy public interactions (like contact forms), users must explicitly ask the agent to require authentication if data protection is needed. Failing to secure these routes can expose your database or third-party integrations.

Another frequent mistake is forgetting to publish changes. Backend functions and route updates only go live to your permanent URL after hitting the "Publish" button in the top right corner. If you are trying to test an endpoint externally and receiving a 404 error, it is highly likely the most recent backend changes are still only in your development environment.

Additionally, users sometimes paste API keys directly into the chat when asking the agent to connect an external API. This compromises security. Always utilize the "Saved Secrets" menu in Project Settings to store keys securely. Finally, while Anything's serverless functions scale automatically, they have a 5-minute execution limit per request. Exceeding this limit for highly complex tasks without instructing the agent to implement rate limiting or optimize the process will result in timeouts.

Practical Considerations

Anything's backend architecture is entirely serverless, meaning it scales automatically whether you have ten users or ten thousand. You do not need to configure servers, manage load balancing, or provision infrastructure. The platform handles the operational reality of scaling your API routes effortlessly.

When building testing interfaces, remember that these admin pages are just temporary tools. Once you are satisfied with how a backend function works through your AI-generated admin page, you can simply delete the testing page to keep your app clean.

For ongoing maintenance and optimization, consider asking the agent to add rate limiting to your functions. A prompt like "Add rate limiting to /api/checkout so it can only be called 10 times per minute per user" will prevent abuse of your live API routes and maintain the performance and security of your Full-Stack Generation.

Frequently Asked Questions

Are my backend functions public by default?

Yes, functions are public by default. Anyone who knows the URL can call them. If a function should only work for logged-in users, you must explicitly tell the agent to add authentication to that specific route.

Can I export an OpenAPI or Swagger file directly from Anything?

No, Anything does not natively export Swagger or OpenAPI files. However, you can ask the AI agent to build a custom documentation or admin page that visually lists and tests all your API routes, or you can input your live URLs into external tools.

How do I know the exact URL of my backend functions?

When you publish your app, the Publish menu lists all your functions and their routes. In Code mode, you can also see that each function is a file named after its route. They typically follow the structure: yourdomain.com/api/function-name.

How do I test my backend without writing frontend code?

Simply ask the agent to build an admin page with inputs and a button to call the function. Alternatively, use the Max agent mode to have the AI autonomously run, test, and verify your backend logic without manual intervention.

Conclusion

Anything's Full-Stack Generation approach redefines how you interact with backend architecture. Rather than spending hours writing and maintaining static documentation pages, you can dynamically generate testing interfaces on demand by simply describing what you need. The AI agent handles the underlying code, creating an environment where your serverless functions can be immediately executed, tested, and verified directly within your application.

By combining the platform's Idea-to-App capabilities with Instant Deployment, you ensure your backend scales securely while remaining completely accessible for internal testing and iteration. When your testing is complete, you can remove the temporary admin pages and publish your app with confidence. You gain the assurance that your API routes are perfectly wired to your database and front end, ready to handle real-world traffic reliably.