HTTP API: Expose Resources & Prompts Guide

Hey guys! Today, we're diving deep into how to expose resources and prompts via HTTP API, a crucial step in making our systems more accessible and integrated. We'll be focusing on a specific issue: adding REST endpoints to list and read MCP (Management Control Plane) resources and prompts from a Fastify server. This guide will walk you through the objective, acceptance criteria, and the commands you'll need to get this done. Let's jump right in!

Objective: REST Endpoints for MCP Resources and Prompts

The main objective here is to add REST endpoints that allow us to interact with MCP resources and prompts using simple HTTP requests. This means we'll be creating pathways to list and read these resources directly from our Fastify server. Why is this important? Well, exposing these resources via an API makes it easier for other systems and applications to access and use them. Think of it as opening up our system to the world, allowing for seamless integration and automation.

To break it down, we need to implement the following:

1. Listing Resources: We'll create an endpoint that returns a list of all available MCP resources.
2. Reading Resources: We'll create an endpoint that allows us to retrieve a specific resource by its URI (Uniform Resource Identifier).
3. Listing Prompts: Similarly, we'll create an endpoint to list all available prompts.
4. Reading Prompts: And finally, an endpoint to retrieve a specific prompt by its name.

Why is this so critical, you ask? Exposing resources and prompts via HTTP APIs unlocks a world of possibilities. Imagine being able to programmatically fetch documentation, validate configurations, or even trigger automated actions based on system prompts. This level of accessibility is a game-changer for automation, monitoring, and overall system management. By implementing these endpoints, we're not just adding features; we're laying the foundation for a more dynamic and responsive system.

We're essentially building a bridge between our internal MCP and the external world. This bridge allows authorized users and systems to interact with our resources in a standardized, predictable way. This predictability is key for building reliable and scalable applications. The more accessible our resources are, the easier it is to build tools and workflows around them. Think of it as empowering developers and operators to work more efficiently and effectively. And that, my friends, is a big win for everyone involved.

Moreover, exposing resources and prompts via HTTP APIs promotes a microservices architecture. By decoupling the MCP from other systems, we can update and maintain it independently without disrupting other services. This modularity is crucial for building resilient and scalable systems. Each service can focus on its specific responsibilities, leading to a more manageable and maintainable codebase. In the long run, this approach saves time, reduces errors, and allows us to iterate faster.

Finally, let's not forget the security aspect. By implementing proper authentication and policy enforcement, we can ensure that only authorized users and systems can access our resources. This is paramount for protecting sensitive data and preventing unauthorized modifications. We'll delve deeper into the security aspects later, but it's crucial to keep this in mind from the outset. We're not just making our resources accessible; we're making them accessible securely.

Acceptance Criteria: Ensuring Everything Works as Expected

Now, let's talk about the acceptance criteria. These are the specific conditions that must be met to consider this task complete. Think of them as the checklist we need to go through to ensure everything works as expected. Here’s the breakdown:

1. GET /resources and GET /resources/:uri Endpoints: We need to add these endpoints to our Fastify server. The /resources endpoint should proxy to the listResources function in our MCP, returning a list of all resources. The /resources/:uri endpoint should proxy to the readResource function, allowing us to fetch a specific resource by its URI. These endpoints are the cornerstone of resource accessibility, providing the foundation for interacting with our system's inventory.

2. GET /prompts and GET /prompts/:name Endpoints: Similarly, we need to add these endpoints for prompts. The /prompts endpoint should proxy to the listPrompts function, returning a list of all available prompts. The /prompts/:name endpoint should proxy to the getPrompt function, allowing us to fetch a specific prompt by its name. These endpoints are essential for driving dynamic behavior and automated responses within our system, enabling flexible and context-aware interactions.

3. Authentication and Policy Enforcement: This is a big one. We need to ensure that all these endpoints require authentication and enforce appropriate policies. This means only authorized users and systems can access these resources. Security is paramount, guys! We need to protect our resources from unauthorized access and ensure data integrity. This involves implementing robust authentication mechanisms and defining clear access control policies. Think of it as building a secure gate around our resources, allowing only those with the right credentials to enter.

4. JSON Response Format: The endpoints should return resource and prompt metadata and contents in a JSON response format. This format should match our existing API conventions. Consistency is key here. By adhering to a standard JSON response format, we make it easier for other systems to parse and use our data. This reduces integration complexity and promotes interoperability. It's like speaking a common language, ensuring that everyone understands each other.

5. Integration Tests: We need to add integration tests to verify the retrieval of various resources, including documentation, invariants, policies, CODEOWNERS files, and prompts. These tests are crucial for ensuring that our endpoints function correctly and that our resources are accessible as expected. Think of them as the final exam, ensuring that everything we've built works flawlessly. These tests will help us catch any bugs or issues early on, preventing them from making their way into production.

These acceptance criteria are not just a checklist; they're a blueprint for success. By meeting these criteria, we ensure that our API is functional, secure, and consistent. This builds trust and reliability, making our system a valuable asset for our users and other systems.

Why are integration tests so important? They simulate real-world scenarios, ensuring that different parts of our system work together seamlessly. They validate the entire flow, from the initial request to the final response. This gives us confidence that our API is not just working in isolation but also in the context of the broader system.

Commands to Run: Getting Our Hands Dirty

Alright, let’s get to the nitty-gritty. To make sure everything is in tip-top shape, we need to run a couple of commands. These commands will build our project and run our tests, ensuring that everything is working as expected.

1. pnpm -w build: This command builds our project. The -w flag tells pnpm to run the build script in all workspaces. This ensures that all our packages are built and ready to go. Think of it as compiling our code and preparing it for deployment. A successful build is the first step towards a successful implementation. It's like laying the foundation for a strong building. Without a solid foundation, the rest of the structure is likely to crumble.

   • Why is building important? Building transforms our source code into executable code. It also performs various optimizations, making our application more efficient. A well-built application is faster, more reliable, and easier to deploy. It's the engine that powers our system, so we need to make sure it's running smoothly.

2. pnpm -w test: This command runs our tests. Again, the -w flag tells pnpm to run the test script in all workspaces. This ensures that all our tests are executed, giving us a comprehensive view of the health of our codebase. These tests will verify that our new endpoints are working correctly and that we haven't introduced any regressions. Think of it as putting our code through a rigorous workout, ensuring that it can handle the pressure.

   • Why are tests crucial? Tests are our safety net. They catch bugs early, preventing them from making their way into production. They also serve as documentation, illustrating how our code is supposed to work. Comprehensive testing is a hallmark of a robust and reliable system. It's like having a quality control team that ensures every product meets our high standards.

By running these commands, we can be confident that our changes are well-tested and that we're delivering a high-quality solution. This is not just about making things work; it's about making them work reliably and consistently. It's about building a system that we can trust.

These commands are not just steps; they're a ritual. They represent our commitment to quality and reliability. They're the final checks that ensure we're delivering a product that we can be proud of. So, let's run these commands with confidence, knowing that we're building something great.

Conclusion: Putting It All Together

So, there you have it! We've covered the objective of exposing resources and prompts via HTTP API, the acceptance criteria that define our success, and the commands we need to run to ensure everything is working smoothly. This is a significant step towards making our systems more accessible, integrated, and secure. By adding these REST endpoints, we're unlocking a world of possibilities for automation, monitoring, and overall system management.

Remember, this is not just about adding features; it's about building a foundation for a more dynamic and responsive system. It's about empowering developers and operators to work more efficiently and effectively. And it's about delivering a high-quality solution that we can trust. By following this guide, you'll be well on your way to achieving these goals. Keep up the great work, guys!

We've essentially created a robust bridge between our internal MCP and the external world, ensuring authorized users can interact securely. By understanding and implementing these steps, you're not just completing a task; you're contributing to a more interconnected and efficient future for our systems. This level of accessibility and integration is a game-changer, paving the way for seamless workflows and streamlined processes.

In summary, we've built a pathway to list and read MCP resources and prompts using simple HTTP requests, making our systems more accessible and integrated. This comprehensive approach, encompassing objectives, acceptance criteria, and commands, ensures that we're not just building a feature, but laying the groundwork for a more dynamic and responsive system. Now, go forth and implement these concepts, and witness the power of accessible and well-managed resources!