Overview of the MCP PHP Server SDK

The MCP PHP Server is a fully‑featured implementation of the Model Context Protocol (MCP) written in modern PHP. It allows developers to expose tools and resources that a Large Language Model (LLM) can invoke or consume, thereby turning ordinary PHP applications into intelligent backends for AI assistants. By adhering to the open MCP specification, the server can be paired with any LLM that understands the protocol, such as Claude or other next‑generation models.

Solving a Common Integration Gap

AI assistants often need to perform domain‑specific actions—querying databases, interacting with third‑party APIs, or retrieving static content. Traditionally developers would have to write custom adapters or REST endpoints for each model and then manually handle authentication, request parsing, and response formatting. The MCP PHP Server removes this friction by providing a standardized contract: LLMs request tools or resources through JSON‑RPC, and the server returns results in a consistent format. This eliminates boilerplate code, reduces integration time, and ensures that the LLM can discover capabilities automatically.

Core Functionality

The SDK offers a server skeleton that handles JSON‑RPC plumbing, error handling, and capability registration. Two primary capabilities are exposed:

• Tools – executable actions that the LLM can invoke, such as “echo” or more complex business logic. Tools are defined via PHP attributes, making the configuration declarative and type‑safe.
• Resources – static or dynamic data that the LLM can read, like configuration files or database snapshots. Resources are also defined with attributes, allowing fine‑grained control over URI schemes and content types.

Transport layers are pluggable: a lightweight for command‑line or local debugging, and an that can be deployed behind Apache/Nginx with PHP‑FPM. This flexibility lets teams run the same server in development, staging, or production without code changes.

Real‑World Use Cases

• Internal tooling: Expose a PHP‑based inventory system as a tool that an LLM can query to provide real‑time stock levels.
• Data retrieval: Serve CSV or JSON files from a legacy system as resources, enabling the model to reference up‑to‑date reports.
• Automation: Combine multiple tools—email sending, calendar booking, and notification posting—into a single MCP server that an assistant can orchestrate.
• Testing & prototyping: Use the STDIO transport to quickly prototype tool logic and validate JSON‑RPC exchanges before exposing them over HTTP.

Integration with AI Workflows

Once the MCP server is running, an LLM client simply registers its endpoint and discovers available tools/resources via the MCP discovery mechanism. The server’s attribute‑based configuration translates PHP classes into MCP descriptors, so developers can focus on business logic rather than protocol quirks. Because the server speaks JSON‑RPC, it blends seamlessly into existing microservice architectures or serverless functions.

Unique Advantages

• Zero‑configuration attribute system: Define tools and resources directly in PHP classes with minimal boilerplate.
• Dual transport support: Rapid local testing via STDIO and production readiness with HTTP out of the box.
• Strict MCP compliance: Guarantees interoperability with any compliant LLM, future‑proofing the integration.
• Extensible capability model: Add new capabilities or custom transports without modifying core logic.

In summary, the MCP PHP Server SDK transforms a standard PHP application into an AI‑ready service with minimal effort. By handling protocol intricacies, providing declarative tooling, and offering flexible transports, it empowers developers to build robust, discoverable AI assistants that can execute code, fetch data, and integrate seamlessly into modern workflows.