fix: return empty list instead of raising error when integrationDepen…

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "sap-cloud-sdk"
-version = "0.39.0"
+version = "0.39.1"
 description = "SAP Cloud SDK for Python"
 readme = "README.md"
 license = "Apache-2.0"

src/sap_cloud_sdk/agentgateway/_customer.py

@@ -642,7 +642,7 @@ async def _list_server_tools(
         async with streamable_http_client(url, http_client=http_client) as (
             read,
             write,
-            _,
+            *_,
         ):
             async with ClientSession(read, write) as session:
                 init_result = await session.initialize()
@@ -672,6 +672,25 @@ async def _list_server_tools(
                 ]
 
 
+def _log_mcp_server_error(ord_id: str, exc: BaseException) -> None:
+    # Unwrap ExceptionGroup from anyio to surface the real HTTP error body
+    if isinstance(exc, BaseExceptionGroup):
+        for inner in exc.exceptions:
+            _log_mcp_server_error(ord_id, inner)
+        return
+    if isinstance(exc, httpx.HTTPStatusError):
+        logger.error(
+            "Failed to load tools from %s (HTTP %d): %s",
+            ord_id,
+            exc.response.status_code,
+            exc.response.text[:500],
+        )
+    else:
+        logger.exception(
+            "Failed to load tools from %s — skipping", ord_id, exc_info=exc
+        )
+
+
 async def get_mcp_tools_customer(
     credentials: CustomerCredentials,
     system_token: str,
@@ -689,16 +708,14 @@ async def get_mcp_tools_customer(
 
     Returns:
         List of MCPTool objects from all servers.
-
-    Raises:
-        AgentGatewaySDKError: If integrationDependencies is empty.
     """
     dependencies = credentials.integration_dependencies
 
     if not dependencies:
-        raise AgentGatewaySDKError(
+        logger.warning(
             "integrationDependencies is empty in credentials — no MCP servers configured."
         )
+        return []
 
     logger.info("Discovering tools from %d MCP server(s)", len(dependencies))
 
@@ -717,8 +734,8 @@ async def get_mcp_tools_customer(
             server_tools = await _list_server_tools(url, system_token, timeout)
             tools.extend(server_tools)
             logger.debug("Loaded %d tool(s) from %s", len(server_tools), dep.ord_id)
-        except Exception:
-            logger.exception("Failed to load tools from %s — skipping", dep.ord_id)
+        except Exception as exc:
+            _log_mcp_server_error(dep.ord_id, exc)
 
     logger.info(
         "Loaded %d MCP tool(s) from %d server(s)", len(tools), len(dependencies)
@@ -758,7 +775,7 @@ async def call_mcp_tool_customer(
         async with streamable_http_client(tool.url, http_client=http_client) as (
             read,
             write,
-            _,
+            *_,
         ):
             async with ClientSession(read, write) as session:
                 await session.initialize()
@@ -769,4 +786,9 @@ async def call_mcp_tool_customer(
                     return ""
 
                 first = result.content[0]
-                return str(getattr(first, "text", ""))
+                text = str(getattr(first, "text", ""))
+
+                if result.isError:
+                    logger.error("Tool '%s' returned an error: %s", tool.name, text)
+
+                return text

src/sap_cloud_sdk/agentgateway/_lob.py

@@ -290,6 +290,26 @@ def _fetch_user_auth_sync():
     return token, gateway_url
 
 
+def _log_mcp_server_error(fragment_name: str, exc: BaseException) -> None:
+    if isinstance(exc, BaseExceptionGroup):
+        for inner in exc.exceptions:
+            _log_mcp_server_error(fragment_name, inner)
+        return
+    if isinstance(exc, httpx.HTTPStatusError):
+        logger.error(
+            "Failed to load tools from fragment '%s' (HTTP %d): %s",
+            fragment_name,
+            exc.response.status_code,
+            exc.response.text[:500],
+        )
+    else:
+        logger.exception(
+            "Failed to load tools from fragment '%s' — skipping",
+            fragment_name,
+            exc_info=exc,
+        )
+
+
 async def list_server_tools(
     dest_url: str, auth_token: str, fragment_name: str, timeout: float
 ) -> list[MCPTool]:
@@ -313,7 +333,7 @@ async def list_server_tools(
         async with streamable_http_client(dest_url, http_client=http_client) as (
             read,
             write,
-            _,
+            *_,
         ):
             async with ClientSession(read, write) as session:
                 init_result = await session.initialize()
@@ -388,11 +408,8 @@ async def get_mcp_tools_lob(
                 len(server_tools),
                 fragment_name,
             )
-        except Exception:
-            logger.exception(
-                "Failed to load tools from fragment '%s' — skipping",
-                fragment_name,
-            )
+        except Exception as exc:
+            _log_mcp_server_error(fragment_name, exc)
 
     logger.info("Loaded %d MCP tool(s) from %d fragment(s)", len(tools), len(fragments))
     return tools
@@ -427,7 +444,7 @@ async def call_mcp_tool_lob(
         async with streamable_http_client(tool.url, http_client=http_client) as (
             read,
             write,
-            _,
+            *_,
         ):
             async with ClientSession(read, write) as session:
                 await session.initialize()
@@ -436,7 +453,12 @@ async def call_mcp_tool_lob(
                     logger.warning("Tool '%s' returned empty content", tool.name)
                     return ""
                 first = result.content[0]
-                return str(getattr(first, "text", ""))
+                text = str(getattr(first, "text", ""))
+
+                if result.isError:
+                    logger.error("Tool '%s' returned an error: %s", tool.name, text)
+
+                return text
 
 
 async def _fetch_agent_card(

tests/agentgateway/unit/test_customer.py

@@ -464,8 +464,8 @@ def credentials(self):
         )
 
     @pytest.mark.asyncio
-    async def test_raises_when_empty_dependencies(self):
-        """Raise error when integrationDependencies is empty."""
+    async def test_returns_empty_when_empty_dependencies(self):
+        """Return empty list when integrationDependencies is empty."""
         credentials = CustomerCredentials(
             token_service_url="https://ias.example.com/oauth2/token",
             client_id="test-client",
@@ -474,10 +474,8 @@ async def test_raises_when_empty_dependencies(self):
             gateway_url="https://agw.example.com",
             integration_dependencies=[],
         )
-        with pytest.raises(
-            AgentGatewaySDKError, match="integrationDependencies is empty"
-        ):
-            await get_mcp_tools_customer(credentials, "system-token", 60.0)
+        result = await get_mcp_tools_customer(credentials, "system-token", 60.0)
+        assert result == []
 
     @pytest.mark.asyncio
     async def test_discovers_tools_from_credentials(self, credentials):