server2

server2

A simple MCP server based on https://github.com/modelcontextprotocol/go-sdk with tools for time, HTTP header testing, and slow response testing.

Test Go binary

MCP_TRANSPORT=http PORT=9091 go run main.go
MCP=http://localhost:9091/mcp

Build and run Dockerfile

docker build --load --tag mcp-test2 .
docker run --publish 9091:9090 --env MCP_TRANSPORT=http --env PORT=9090 mcp-test2
MCP=http://localhost:9091/mcp

Testing the MCP server with the @modelcontextprotocol/inspector

Run DANGEROUSLY_OMIT_AUTH=true npx @modelcontextprotocol/inspector

Testing the MCP server with curl

First, initialize the server:

curl --include -X POST -H "Content-Type: application/json" -H "Accept: application/json, text/event-stream" ${MCP} --data '
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "initialize",
  "params": {
    "protocolVersion": "2025-06-18",
    "capabilities": {
      "roots": {
        "listChanged": true
      },
      "sampling": {}
    },
    "clientInfo": {
      "name": "ExampleClient",
      "version": "1.0.0"
    }
  }
}
' | tee /tmp/init-response.txt

Next, complete the initialization:

SESSION_ID=$(cat /tmp/init-response.txt | grep -i mcp-session-id: | sed 's/mcp-session-id: //I' | sed 's/\r//g')
echo SESSION_ID is ${SESSION_ID}
curl -v -X POST -H "mcp-session-id: ${SESSION_ID}" -H "Content-Type: application/json" -H "Accept: application/json, text/event-stream" ${MCP} --data '
{
  "jsonrpc": "2.0",
  "method": "notifications/initialized"
}
'

(Optional) List tools:

curl -v ${MCP} -H "mcp-session-id: ${SESSION_ID}" -H "Content-Type: application/json" -H "Accept: application/json, text/event-stream" --silent --data '
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/list"
}
' | jq

Inspect HTTP headers sent to server:

curl -v ${MCP} -H "mcp-session-id: ${SESSION_ID}" -H "Content-Type: application/json" -H "Accept: application/json, text/event-stream" --silent --data '
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "headers"
  }
}
' | jq

Make a slow call with progress updates:

curl -v ${MCP} -H "mcp-session-id: ${SESSION_ID}" -H "Content-Type: application/json" -H "Accept: application/json, text/event-stream" --data '
{
  "jsonrpc": "2.0",
  "id": 3,
  "method": "tools/call",
  "params": {
    "name": "slow",
    "arguments": {
      "seconds": 5
    },
    "_meta": {
      "progressToken": "abc123"
    }
  }
}
'

Security options

To require a bearer token, define EXPECTED_AUTH

• EXPECTED_AUTH="Bearer 1234" MCP_TRANSPORT=http PORT=9091 go run main.go
• docker run --publish 9091:9090 --EXPECTED_AUTH="Bearer 1234" --env MCP_TRANSPORT=http --env PORT=9090 mcp-test2

Then, before Connecting in the MCP Inspector console, expand Authorization and set the Bearer Token value to 1234. (Note that the MCP inspector prepends this with "Bearer ", so the value set in the MCP Inspector UI doesn't match exactly with what the test MCP server receives).