Everything
Official MCP reference and test server that exercises the full protocol — tools, prompts, resources, sampling, elicitation, and logging — intended for MCP client developers rather than production use.
Tools
echo
Echo back the provided message string, used to demonstrate the simplest possible MCP tool call.
get-annotated-message
Return a message annotated with priority and audience metadata based on the requested message type.
get-env
Return all environment variables from the running server process as pretty-printed JSON text.
get-resource-links
Return an introductory text block followed by several resource_link items for the client to resolve.
get-resource-reference
Return a resource reference for a given resource type (text or blob) and a positive-integer resource id.
get-roots-list
Return the most recent list of filesystem roots that the client sent to the server.
get-structured-content
Demonstrate structured tool responses, accepting a location input and returning both content and structured data.
get-sum
Calculate and return the sum of two provided numbers, demonstrating a simple typed-input tool.
get-tiny-image
Return a tiny PNG of the MCP logo as an image content item to demonstrate binary tool output.
gzip-file-as-resource
Fetch data, gzip-compress it, and register the result as a session resource with a gzip MIME type.
simulate-research-query
Demonstrate MCP Tasks with a simulated multi-stage research operation that streams intermediate progress.
toggle-simulated-logging
Start or stop simulated random-severity log message emission for the current session.
toggle-subscriber-updates
Start or stop simulated resource-update notifications for URIs the client has subscribed to.
trigger-elicitation-request
Issue a form-mode elicitation request to the client using fields of various data types.
trigger-elicitation-request-async
Demonstrate bidirectional MCP tasks using a server-initiated asynchronous elicitation request.
trigger-long-running-operation
Simulate a multi-step, long-running operation over a given duration and number of steps with progress updates.
trigger-sampling-request
Issue a sampling/createMessage request so the client's language model generates a completion for the server.
trigger-sampling-request-async
Demonstrate bidirectional MCP tasks using a server-initiated asynchronous sampling request.
trigger-url-elicitation
Issue a URL-mode elicitation request to the client, or raise a specific MCP error for testing.