diff --git a/rust/cocoindex/src/ops/py_factory.rs b/rust/cocoindex/src/ops/py_factory.rs
index 94ad4c88..01c3775c 100644
--- a/rust/cocoindex/src/ops/py_factory.rs
+++ b/rust/cocoindex/src/ops/py_factory.rs
@@ -81,7 +81,8 @@ impl PyFunctionExecutor {
                     .transpose()?
                     .as_ref(),
             )
-            .to_result_with_py_trace(py)?;
+            .to_result_with_py_trace(py)
+            .with_context(|| format!("while calling user-configured function"))?;
         Ok(result.into_bound(py))
     }
 }
@@ -230,7 +231,8 @@ impl interface::SimpleFunctionFactory for PyFunctionFactory {
                         PyTuple::new(py, args.into_iter())?,
                         Some(&kwargs.into_py_dict(py)?),
                     )
-                    .to_result_with_py_trace(py)?;
+                    .to_result_with_py_trace(py)
+                    .with_context(|| format!("while building user-configured function"))?;
                 let (result_type, executor) = result
                     .extract::<(crate::py::Pythonized<schema::EnrichedValueType>, Py<PyAny>)>(py)?;
                 Ok((
@@ -253,7 +255,8 @@ impl interface::SimpleFunctionFactory for PyFunctionFactory {
                     Python::with_gil(|py| -> anyhow::Result<_> {
                         let prepare_coro = executor
                             .call_method(py, "prepare", (), None)
-                            .to_result_with_py_trace(py)?;
+                            .to_result_with_py_trace(py)
+                            .with_context(|| format!("while preparing user-configured function"))?;
                         let prepare_fut = from_py_future(
                             py,
                             &pyo3_async_runtimes::TaskLocals::new(
@@ -360,6 +363,7 @@ impl interface::SourceExecutor for PySourceExecutor {
             py_source_executor
                 .call_method(py, "list_async", (pythonize(py, options)?,), None)
                 .to_result_with_py_trace(py)
+                .with_context(|| format!("while listing user-configured source"))
         })?;
 
         // Create a stream that pulls from the Python async iterator one item at a time
@@ -399,7 +403,13 @@ impl interface::SourceExecutor for PySourceExecutor {
                     ),
                     None,
                 )
-                .to_result_with_py_trace(py)?;
+                .to_result_with_py_trace(py)
+                .with_context(|| {
+                    format!(
+                        "while fetching user-configured source for key: {:?}",
+                        &key_clone
+                    )
+                })?;
             let task_locals =
                 pyo3_async_runtimes::TaskLocals::new(py_exec_ctx.event_loop.bind(py).clone());
             Ok(from_py_future(
@@ -439,7 +449,8 @@ impl PySourceExecutor {
         let next_item_coro = Python::with_gil(|py| -> Result<_> {
             let coro = py_async_iter
                 .call_method0(py, "__anext__")
-                .to_result_with_py_trace(py)?;
+                .to_result_with_py_trace(py)
+                .with_context(|| format!("while iterating over user-configured source"))?;
             let task_locals =
                 pyo3_async_runtimes::TaskLocals::new(py_exec_ctx.event_loop.bind(py).clone());
             Ok(from_py_future(py, &task_locals, coro.into_bound(py))?)
@@ -572,7 +583,7 @@ impl PySourceExecutor {
 impl interface::SourceFactory for PySourceConnectorFactory {
     async fn build(
         self: Arc<Self>,
-        _source_name: &str,
+        source_name: &str,
         spec: serde_json::Value,
         context: Arc<interface::FlowInstanceContext>,
     ) -> Result<(
@@ -590,7 +601,13 @@ impl interface::SourceFactory for PySourceConnectorFactory {
             let value_type_result = self
                 .py_source_connector
                 .call_method(py, "get_table_type", (), None)
-                .to_result_with_py_trace(py)?;
+                .to_result_with_py_trace(py)
+                .with_context(|| {
+                    format!(
+                        "while fetching table type from user-configured source `{}`",
+                        source_name
+                    )
+                })?;
             let table_type: schema::EnrichedValueType =
                 depythonize(&value_type_result.into_bound(py))?;
             Ok(table_type)
@@ -619,14 +636,20 @@ impl interface::SourceFactory for PySourceConnectorFactory {
                 table_type.typ
             ),
         };
-
+        let source_name = source_name.to_string();
         let executor_fut = async move {
             // Create the executor using the async create_executor method
             let create_future = Python::with_gil(|py| -> Result<_> {
                 let create_coro = self
                     .py_source_connector
                     .call_method(py, "create_executor", (pythonize(py, &spec)?,), None)
-                    .to_result_with_py_trace(py)?;
+                    .to_result_with_py_trace(py)
+                    .with_context(|| {
+                        format!(
+                            "while constructing executor for user-configured source `{}`",
+                            source_name
+                        )
+                    })?;
                 let task_locals =
                     pyo3_async_runtimes::TaskLocals::new(py_exec_ctx.event_loop.bind(py).clone());
                 let create_future = from_py_future(py, &task_locals, create_coro.into_bound(py))?;
@@ -637,13 +660,25 @@ impl interface::SourceFactory for PySourceConnectorFactory {
 
             let (py_source_executor_context, provides_ordinal) =
                 Python::with_gil(|py| -> Result<_> {
-                    let executor_context =
-                        py_executor_context_result.to_result_with_py_trace(py)?;
+                    let executor_context = py_executor_context_result
+                        .to_result_with_py_trace(py)
+                        .with_context(|| {
+                        format!(
+                            "while getting executor context for user-configured source `{}`",
+                            source_name
+                        )
+                    })?;
 
                     // Get provides_ordinal from the executor context
                     let provides_ordinal = executor_context
                         .call_method(py, "provides_ordinal", (), None)
-                        .to_result_with_py_trace(py)?
+                        .to_result_with_py_trace(py)
+                        .with_context(|| {
+                            format!(
+                                "while calling provides_ordinal for user-configured source `{}`",
+                                source_name
+                            )
+                        })?
                         .extract::<bool>(py)?;
 
                     Ok((executor_context, provides_ordinal))
@@ -743,20 +778,38 @@ impl interface::TargetFactory for PyExportTargetFactory {
                         ),
                         None,
                     )
-                    .to_result_with_py_trace(py)?;
+                    .to_result_with_py_trace(py)
+                    .with_context(|| {
+                        format!(
+                            "while setting up export context for user-configured target `{}`",
+                            &data_collection.name
+                        )
+                    })?;
 
                 // Call the `get_persistent_key` method to get the persistent key.
                 let persistent_key = self
                     .py_target_connector
                     .call_method(py, "get_persistent_key", (&py_export_ctx,), None)
-                    .to_result_with_py_trace(py)?;
+                    .to_result_with_py_trace(py)
+                    .with_context(|| {
+                        format!(
+                            "while getting persistent key for user-configured target `{}`",
+                            &data_collection.name
+                        )
+                    })?;
                 let persistent_key: serde_json::Value =
                     depythonize(&persistent_key.into_bound(py))?;
 
                 let setup_state = self
                     .py_target_connector
                     .call_method(py, "get_setup_state", (&py_export_ctx,), None)
-                    .to_result_with_py_trace(py)?;
+                    .to_result_with_py_trace(py)
+                    .with_context(|| {
+                        format!(
+                            "while getting setup state for user-configured target `{}`",
+                            &data_collection.name
+                        )
+                    })?;
                 let setup_state: serde_json::Value = depythonize(&setup_state.into_bound(py))?;
 
                 anyhow::Ok((py_export_ctx, persistent_key, setup_state))
@@ -770,7 +823,13 @@ impl interface::TargetFactory for PyExportTargetFactory {
                         let prepare_coro = factory
                             .py_target_connector
                             .call_method(py, "prepare_async", (&py_export_ctx,), None)
-                            .to_result_with_py_trace(py)?;
+                            .to_result_with_py_trace(py)
+                            .with_context(|| {
+                                format!(
+                                    "while preparing user-configured target `{}`",
+                                    &data_collection.name
+                                )
+                            })?;
                         let task_locals = pyo3_async_runtimes::TaskLocals::new(
                             py_exec_ctx.event_loop.bind(py).clone(),
                         );
@@ -839,7 +898,10 @@ impl interface::TargetFactory for PyExportTargetFactory {
                     ),
                     None,
                 )
-                .to_result_with_py_trace(py)?;
+                .to_result_with_py_trace(py)
+                .with_context(|| {
+                    format!("while calling check_state_compatibility in user-configured target")
+                })?;
             let compatibility: SetupStateCompatibility = depythonize(&result.into_bound(py))?;
             Ok(compatibility)
         })?;
@@ -851,7 +913,10 @@ impl interface::TargetFactory for PyExportTargetFactory {
             let result = self
                 .py_target_connector
                 .call_method(py, "describe_resource", (pythonize(py, key)?,), None)
-                .to_result_with_py_trace(py)?;
+                .to_result_with_py_trace(py)
+                .with_context(|| {
+                    format!("while calling describe_resource in user-configured target")
+                })?;
             let description = result.extract::<String>(py)?;
             Ok(description)
         })
@@ -908,7 +973,10 @@ impl interface::TargetFactory for PyExportTargetFactory {
                     (pythonize(py, &setup_changes)?,),
                     None,
                 )
-                .to_result_with_py_trace(py)?;
+                .to_result_with_py_trace(py)
+                .with_context(|| {
+                    format!("while calling apply_setup_changes_async in user-configured target")
+                })?;
             let task_locals =
                 pyo3_async_runtimes::TaskLocals::new(py_exec_ctx.event_loop.bind(py).clone());
             Ok(from_py_future(
@@ -918,7 +986,11 @@ impl interface::TargetFactory for PyExportTargetFactory {
             )?)
         })?
         .await;
-        Python::with_gil(move |py| py_result.to_result_with_py_trace(py))?;
+        Python::with_gil(move |py| {
+            py_result
+                .to_result_with_py_trace(py)
+                .with_context(|| format!("while applying setup changes in user-configured target"))
+        })?;
 
         Ok(())
     }
@@ -969,7 +1041,8 @@ impl interface::TargetFactory for PyExportTargetFactory {
             let result_coro = self
                 .py_target_connector
                 .call_method(py, "mutate_async", (py_args,), None)
-                .to_result_with_py_trace(py)?;
+                .to_result_with_py_trace(py)
+                .with_context(|| format!("while calling mutate_async in user-configured target"))?;
             let task_locals =
                 pyo3_async_runtimes::TaskLocals::new(py_exec_ctx.event_loop.bind(py).clone());
             Ok(from_py_future(
@@ -980,7 +1053,11 @@ impl interface::TargetFactory for PyExportTargetFactory {
         })?
         .await;
 
-        Python::with_gil(move |py| py_result.to_result_with_py_trace(py))?;
+        Python::with_gil(move |py| {
+            py_result
+                .to_result_with_py_trace(py)
+                .with_context(|| format!("while applying mutations in user-configured target"))
+        })?;
         Ok(())
     }
 }