Testing MCP Servers

Test a UiPath MCP Server directly, outside any AI client, using the UiPath MCP Inspector, the open-source MCP Inspector, cURL, or Postman.

Before connecting an MCP Server to an AI client, test the connection and tool behavior directly. Testing outside an AI client lets you isolate whether an issue originates in the MCP Server, its authentication, or the AI client.

Testing with the UiPath MCP Inspector

The UiPath MCP Inspector runs inside Orchestrator and requires no separate setup.

Access the Inspector

1. En la página Servidores MCP, selecciona un servidor MCP.

2. Select the Inspector icon.

   

Call a tool

1. Select a tool from the list.

2. Enter the tool's input parameters.

3. Select Invoke to inspect the result.

   

Testing with the MCP Inspector (CLI)

The MCP Inspector is an open-source tool that connects to any MCP Server over Streamable HTTP.

Requisitos previos

• Node.js is installed to run the npx command.
• The MCP Server URL, available from the MCP Servers page in Orchestrator.
• A bearer token. For the simplest option, use a personal access token (PAT). For other supported token types, check MCP Server authentication.

1. From a terminal, run the following command. It is the same on macOS, Linux, and Windows (PowerShell 7 or Git Bash):

   npx @modelcontextprotocol/inspector@0.22.0
   

   The command opens the Inspector web UI in your browser.

2. Enter the MCP Server URL.

3. Select Streamable HTTP as the transport type.

4. In the Authentication section, enter the token in the format Bearer <token>.

5. Select Connect.

   

Resultado

Once connected, you can:

• List tools to verify all your tools appear with correct JSON schemas.
• Call tools to execute tools with test inputs and inspect responses.
• Watch the session to see the initialize → initialized → request lifecycle in real time.
• Validate schemas to catch type mismatches before they hit an LLM.

Testing with cURL

Use cURL to send raw JSON-RPC requests and inspect the full request/response cycle, including headers.

Requisitos previos

• A bearer token. Check MCP Server authentication for supported methods.
• The MCP Server URL, available from the MCP Servers page in Orchestrator.

1. Set the token and server URL as environment variables:

   TOKEN="your-bearer-token"
   SERVER_URL="https://cloud.uipath.com/{org}/{tenant}/agenthub_/mcp/{folder}/{slug}"
   

2. Initialize the MCP session:

   curl -v -X POST "$SERVER_URL" \
     -H "Authorization: Bearer $TOKEN" \
     -H "Content-Type: application/json" \
     -H "Accept: application/json, text/event-stream" \
     -d '{
       "jsonrpc": "2.0",
       "id": 1,
       "method": "initialize",
       "params": {
         "protocolVersion": "2025-06-18",
         "capabilities": {},
         "clientInfo": {"name": "curl-test", "version": "1.0"}
       }
     }'
   

   Use the -v flag to see response headers, and save the mcp-session-id header value. Every subsequent request needs it.

   Nota:

   UiPath MCP Servers support protocol version 2025-06-18. Sending 2025-11-25 (the latest MCP spec version) may work, since the server responds with the version it supports, but use 2025-06-18 to avoid unsupported behavior.

3. Send the initialized notification:

   curl -X POST "$SERVER_URL" \
     -H "Authorization: Bearer $TOKEN" \
     -H "Content-Type: application/json" \
     -H "mcp-session-id: $SESSION_ID" \
     -d '{"jsonrpc": "2.0", "method": "notifications/initialized"}'
   

   The server responds with 202 Accepted and no body. The server requires this notification before it processes tool requests.

4. List the available tools:

   curl -X POST "$SERVER_URL" \
     -H "Authorization: Bearer $TOKEN" \
     -H "mcp-session-id: $SESSION_ID" \
     -H "Content-Type: application/json" \
     -d '{
       "jsonrpc": "2.0",
       "id": 2,
       "method": "tools/list"
     }'
   

5. Call a tool:

   curl -X POST "$SERVER_URL" \
     -H "Authorization: Bearer $TOKEN" \
     -H "mcp-session-id: $SESSION_ID" \
     -H "Content-Type: application/json" \
     -d '{
       "jsonrpc": "2.0",
       "id": 3,
       "method": "tools/call",
       "params": {
         "name": "add",
         "arguments": {"a": 5, "b": 3}
       }
     }'
   

6. Close the session:

   curl -X DELETE "$SERVER_URL" \
     -H "Authorization: Bearer $TOKEN" \
     -H "mcp-session-id: $SESSION_ID"
   

Testing with Postman

Postman supports MCP requests natively.

1. Create an MCP request in your collection.
2. Select HTTP as the transport, for Streamable HTTP.
3. Enter the MCP Server URL.
4. In the Authorization tab, configure Bearer Token authentication with your token.
5. Select Connect.

Postman handles the session lifecycle, including initialize and notifications/initialized, automatically.

Consejo:

To send raw JSON-RPC requests manually instead, for example to control each request and response individually, use Postman as a plain REST client and follow the same request flow as Testing with cURL.