fix(agentgateway): handle empty MCP tool list and guard against null result.tools

Author: ricardosrib

src/sap_cloud_sdk/agentgateway/_customer.py

@@ -666,6 +666,7 @@ async def _list_server_tools(
 
                 server_name = init_result.serverInfo.name
                 result = await session.list_tools()
+                tools = result.tools or []
 
                 return [
                     MCPTool(
@@ -675,7 +676,7 @@ async def _list_server_tools(
                         input_schema=t.inputSchema or {},
                         url=url,
                     )
-                    for t in result.tools
+                    for t in tools
                 ]
 
 

src/sap_cloud_sdk/agentgateway/_lob.py

@@ -30,14 +30,14 @@
     FragmentLabel,
     get_ias_fragment_name,
     get_ias_user_fragment_name,
-    list_mcp_fragments,
     list_a2a_fragments,
+    list_mcp_fragments,
 )
 from sap_cloud_sdk.agentgateway._models import (
-    JsonRpcError,
     Agent,
     AgentCard,
     AgentCardFilter,
+    JsonRpcError,
     MCPTool,
     MCPToolFilter,
 )
@@ -387,6 +387,11 @@ async def list_server_tools(
                     else fragment_name
                 )
                 result = await session.list_tools()
+                tools = result.tools or []
+                if not tools:
+                    logger.info(
+                        "No tools returned by AGW for fragment '%s'", fragment_name
+                    )
                 return [
                     MCPTool(
                         name=t.name,
@@ -396,7 +401,7 @@ async def list_server_tools(
                         url=dest_url,
                         fragment_name=fragment_name,
                     )
-                    for t in result.tools
+                    for t in tools
                 ]