Fix multi MCP execution and add example servers

docs/examples/multi_mcp_execution.md

@@ -2,8 +2,16 @@
 
 This example demonstrates using a list of MCP servers with an `Agent`.
 
+Start the example servers in separate terminals:
+
+```bash
+python examples/tools/mcp_examples/servers/weather_server.py
+python examples/tools/mcp_examples/servers/news_server.py
+```
+
 ```python
 import os
+import json
 from swarms import Agent
 
 # Configure multiple MCP URLs
@@ -15,11 +23,11 @@ agent = Agent(
     max_loops=1,
 )
 
-# Example payloads produced by your model
+# Example JSON payloads produced by your model
-payloads = [
+response = json.dumps([
     {"function_name": "get_weather", "server_url": "http://localhost:8000/sse", "payload": {"city": "London"}},
     {"function_name": "get_news", "server_url": "http://localhost:9001/sse", "payload": {"topic": "ai"}},
-]
+])
 
-agent.handle_multiple_mcp_tools(agent.mcp_urls, payloads)
+agent.handle_multiple_mcp_tools(agent.mcp_urls, response)
 ```

docs/swarms/structs/agent.md

@@ -483,8 +483,16 @@ print(agent.to_toml())
 Execute tools from multiple MCP servers by providing a list of URLs via the
 `mcp_urls` parameter or the `MCP_URLS` environment variable.
 
+Start the example servers:
+
+```bash
+python examples/tools/mcp_examples/servers/weather_server.py
+python examples/tools/mcp_examples/servers/news_server.py
+```
+
 ```python
 import os
+import json
 from swarms import Agent
 
 # Using an environment variable for server configuration
@@ -497,7 +505,7 @@ agent = Agent(
 )
 
 # Example MCP payloads returned by your model
-mcp_payloads = [
+mcp_response = json.dumps([
     {
         "function_name": "get_price",
         "server_url": "http://localhost:8000/sse",
@@ -508,9 +516,9 @@ mcp_payloads = [
         "server_url": "http://localhost:9001/sse",
         "payload": {"symbol": "BTC"},
     },
-]
+])
 
-agent.handle_multiple_mcp_tools(agent.mcp_urls, mcp_payloads)
+agent.handle_multiple_mcp_tools(agent.mcp_urls, mcp_response)
 ```
 
 ## Auto Generate Prompt + CPU Execution

docs/swarms/structs/agent_mcp.md

@@ -145,6 +145,13 @@ payload in the following format:
 Use `handle_multiple_mcp_tools` to execute each payload across the configured
 servers.
 
+Example servers can be started with:
+
+```bash
+python examples/tools/mcp_examples/servers/weather_server.py
+python examples/tools/mcp_examples/servers/news_server.py
+```
+
 ---
 
 ## Integration Flow

examples/tools/mcp_examples/servers/news_server.py

@@ -0,0 +1,12 @@
+from mcp.server.fastmcp import FastMCP
+
+mcp = FastMCP("NewsServer")
+
+mcp.settings.port = 9001
+
+@mcp.tool(name="get_news", description="Return simple news headline")
+def get_news(topic: str) -> str:
+    return f"Latest {topic} news headline"
+
+if __name__ == "__main__":
+    mcp.run(transport="sse")

examples/tools/mcp_examples/servers/weather_server.py

@@ -0,0 +1,12 @@
+from mcp.server.fastmcp import FastMCP
+
+mcp = FastMCP("WeatherServer")
+
+mcp.settings.port = 8000
+
+@mcp.tool(name="get_weather", description="Return simple weather info")
+def get_weather(city: str) -> str:
+    return f"Weather in {city}: Sunny 22°C"
+
+if __name__ == "__main__":
+    mcp.run(transport="sse")

swarms/structs/agent.py

@@ -1,5 +1,6 @@
 import asyncio
 import json
+import re
 import logging
 import os
 import random
@@ -74,6 +75,7 @@ from swarms.structs.ma_utils import set_random_models_for_agents
 from swarms.tools.mcp_client_call import (
     execute_tool_call_simple,
     get_mcp_tools_sync,
+    execute_mcp_call,
 )
 from swarms.schemas.mcp_schemas import (
     MCPConnection,
@@ -98,6 +100,25 @@ def parse_done_token(response: str) -> bool:
     return "<DONE>" in response
 
 
+def extract_json_from_response(response: str) -> List[Dict[str, Any]]:
+    """Extract a JSON list from a model response string."""
+    if not response:
+        return []
+    if not isinstance(response, str):
+        return response if isinstance(response, list) else []
+    try:
+        return json.loads(response)
+    except json.JSONDecodeError:
+        match = re.search(r"\[[\s\S]*?\]", response)
+        if match:
+            try:
+                return json.loads(match.group(0))
+            except json.JSONDecodeError:
+                pass
+    logger.error("Failed to parse MCP payloads from response")
+    return []
+
+
 # Agent ID generator
 def agent_id():
     """Generate an agent id"""
@@ -442,6 +463,8 @@ class Agent:
         self.sop = sop
         self.sop_list = sop_list
         self.tools = tools
+        # Ensure tool_struct exists even when no tools are provided
+        self.tool_struct = {}
         self.system_prompt = system_prompt
         self.agent_name = agent_name
         self.agent_description = agent_description
@@ -1098,18 +1121,11 @@ class Agent:
 
                         if exists(self.mcp_urls):
                             try:
-                                payload = (
+                                self.handle_multiple_mcp_tools(
-                                    json.loads(response)
+                                    self.mcp_urls,
-                                    if isinstance(response, str)
+                                    response,
-                                    else response
+                                    current_loop=loop_count,
                                 )
-
-                                if isinstance(payload, list):
-                                    self.handle_multiple_mcp_tools(
-                                        self.mcp_urls,
-                                        payload,
-                                        current_loop=loop_count,
-                                    )
                             except Exception as e:
                                 logger.error(
                                     f"Error handling multiple MCP tools: {e}"
@@ -2820,12 +2836,13 @@ class Agent:
     def handle_multiple_mcp_tools(
         self,
         mcp_url_list: List[str],
-        mcp_payloads: List[Dict[str, Any]],
+        response: Union[str, List[Dict[str, Any]]],
         current_loop: int = 0,
     ) -> None:
-        """Execute a list of MCP tool calls across multiple servers."""
+        """Execute multiple MCP tool calls across configured servers."""
 
-        for payload in mcp_payloads:
+        payloads = extract_json_from_response(response)
+        for payload in payloads:
             function_name = payload.get("function_name")
             server_url = payload.get("server_url")
             arguments = payload.get("payload", {})
@@ -2836,25 +2853,31 @@ class Agent:
                 )
                 continue
 
-            try:
+            attempt = 0
-                tool_response = asyncio.run(
+            while attempt < 3:
-                    execute_mcp_call(
+                try:
-                        function_name=function_name,
+                    tool_response = asyncio.run(
-                        server_url=server_url,
+                        execute_mcp_call(
-                        payload=arguments,
+                            function_name=function_name,
+                            server_url=server_url,
+                            payload=arguments,
+                        )
                     )
-                )
+                    self.short_memory.add(
-                self.short_memory.add(
+                        role="Tool Executor",
-                    role="Tool Executor",
+                        content=str(tool_response),
-                    content=str(tool_response),
+                    )
-                )
+                    self.pretty_print(
-                self.pretty_print(
+                        str(tool_response),
-                    str(tool_response), loop_count=current_loop
+                        loop_count=current_loop,
-                )
+                    )
-            except Exception as e:  # noqa: PERF203
+                    break
-                logger.error(
+                except Exception as e:  # noqa: PERF203
-                    f"Error executing {function_name} on {server_url}: {e}"
+                    attempt += 1
-                )
+                    logger.error(
+                        f"Error executing {function_name} on {server_url}: {e}"
+                    )
+                    time.sleep(1)
 
     def temp_llm_instance_for_tool_summary(self):
         return LiteLLM(

tests/structs/test_multi_mcp.py

@@ -1,5 +1,6 @@
 import asyncio
-from swarms.structs.agent import Agent
+import json
+from swarms.structs.agent import Agent, extract_json_from_response
 from swarms.structs.agent import execute_mcp_call
 from unittest.mock import patch
 
@@ -30,9 +31,18 @@ def test_handle_multiple_mcp_tools():
     with patch(
         "swarms.structs.agent.execute_mcp_call", side_effect=fake_exec
     ):
-        agent.handle_multiple_mcp_tools(urls, payloads)
+        agent.handle_multiple_mcp_tools(urls, json.dumps(payloads))
 
     assert called == [
         ("tool1", "http://server1", {"a": 1}),
         ("tool2", "http://server2", {}),
     ]
+
+
+def test_extract_json_from_response():
+    payloads = [
+        {"function_name": "foo", "server_url": "http://x", "payload": {"x": 1}}
+    ]
+    text = "Random text" + json.dumps(payloads) + " end"
+    result = extract_json_from_response(text)
+    assert result == payloads