Function runFakeMCPServer

agent/x/agentmcp/manager_internal_test.go:564–632

runFakeMCPServer implements a minimal JSON-RPC / MCP server over stdin/stdout, just enough for initialize + tools/list.

()

// runFakeMCPServer implements a minimal JSON-RPC / MCP server over
// stdin/stdout, just enough for initialize + tools/list.
func runFakeMCPServer() {
	scanner := bufio.NewScanner(os.Stdin)
	for scanner.Scan() {
		line := scanner.Bytes()

		var req struct {
			JSONRPC string          `json:"jsonrpc"`
			ID      json.RawMessage `json:"id"`
			Method  string          `json:"method"`
		}
		if err := json.Unmarshal(line, &req); err != nil {
			continue
		}

		var resp any
		switch req.Method {
		case "initialize":
			resp = map[string]any{
				"jsonrpc": "2.0",
				"id":      req.ID,
				"result": map[string]any{
					"protocolVersion": "2025-03-26",
					"capabilities": map[string]any{
						"tools": map[string]any{},
					},
					"serverInfo": map[string]any{
						"name":    "fake-server",
						"version": "0.0.1",
					},
				},
			}
		case "notifications/initialized":
			// No response needed for notifications.
			continue
		case "tools/list":
			resp = map[string]any{
				"jsonrpc": "2.0",
				"id":      req.ID,
				"result": map[string]any{
					"tools": []map[string]any{
						{
							"name":        "echo",
							"description": "echoes input",
							"inputSchema": map[string]any{
								"type":       "object",
								"properties": map[string]any{},
							},
						},
					},
				},
			}
		default:
			resp = map[string]any{
				"jsonrpc": "2.0",
				"id":      req.ID,
				"error": map[string]any{
					"code":    -32601,
					"message": "method not found",