An MCP server implementation for Jakarta EE.

Crema turns methods of your CDI beans into Model Context Protocol Tools, Resources and Prompts that AI clients can discover and call. It is a plain library in your WAR, implements the org.mcpjava:mcp-server-api annotations and MCP 2026-07-28 (Streamable HTTP), and runs on any Jakarta EE 10 Web Profile Runtime. It is tested on TomEE, WildFly, Open Liberty and Payara/GlassFish.

<dependency>
    <groupId>io.github.jungm.crema</groupId>
    <artifactId>crema</artifactId>
    <version>0.1.0</version>
</dependency>

Declare an MCP Server:

@ApplicationPath("mcp")
@McpServerInfo(title = "Order Service")
public class OrderMcp extends McpApplication {
}

Then annotate methods of any CDI bean:

@ApplicationScoped
public class OrderFeatures {

    @Inject
    OrderService orders;

    @Tool(description = "Places an order for a customer")
    public Order placeOrder(@ToolArg(description = "Customer number") String customer, List<Item> items) {
        return orders.place(customer, items);
    }

    @ResourceTemplate(uriTemplate = "orders://{id}", name = "order", description = "One order")
    public Order order(String id) {
        return orders.find(id);
    }

    @Prompt(description = "Summarizes a customer's order history")
    public String orderSummary(String customer) {
        return "Summarize the order history of customer " + customer + ".";
    }
}

Deploy the WAR and point an MCP Client at http://<host>:<port>/<context-root>/mcp. To restrict who may call it, see Authentication.

• Getting started: requirements, setup and trying it with curl
• Programming model: Arguments, Injected Parameters, return types, multiple MCP Servers, deployment-time validation
• Configuration: all MicroProfile Config keys
• Security: Origin check and roles
• Authentication: protecting MCP Servers with OAuth, Basic authentication or your own Authenticator
• Limitations: what isn't supported yet
• Building and testing: unit tests, integration tests on four Runtimes, conformance suite

Apache License 2.0