Just some minor stuff:

1) Don't overwrite the message of all Workflow Task Exceptions to say "Something went wrong"
2) log errors when correlation evaluations fail (just so we are aware something isn't working correctly)
3) Dont make all evaluation fuctions require a current task context to execute -- that should be optional.

spiffworkflow-backend/src/spiffworkflow_backend/exceptions/api_error.py

@@ -149,7 +149,7 @@ class ApiError(Exception):
             # Note that WorkflowDataExceptions are also WorkflowTaskExceptions
             return ApiError.from_task(
                 error_code,
-                message,
+                message + ". " + str(exp),
                 exp.task,
                 line_number=exp.line_number,
                 offset=exp.offset,

spiffworkflow-backend/src/spiffworkflow_backend/models/message_instance.py

@@ -6,6 +6,7 @@ from typing import Optional
 from typing import TYPE_CHECKING
 
 from SpiffWorkflow.bpmn.PythonScriptEngine import PythonScriptEngine  # type: ignore
+from flask import current_app
 from sqlalchemy import ForeignKey
 from sqlalchemy.event import listens_for
 from sqlalchemy.orm import relationship
@@ -135,10 +136,15 @@ class MessageInstanceModel(SpiffworkflowBaseDBModel):
                 result = expression_engine._evaluate(
                     correlation_key.retrieval_expression, payload
                 )
-            except Exception:
+            except Exception as e:
                 # the failure of a payload evaluation may not mean that matches for these
                 # message instances can't happen with other messages.  So don't error up.
                 # fixme:  Perhaps log some sort of error.
+                current_app.logger.warning(
+                    "Error evaluating correlation key when comparing send and receive messages." +
+                    f"Expression {correlation_key.retrieval_expression} failed with the error " +
+                    str(e)
+                )
                 return False
             if result != expected_value:
                 return False

spiffworkflow-backend/src/spiffworkflow_backend/services/process_instance_processor.py

@@ -318,18 +318,14 @@ class CustomBpmnScriptEngine(PythonScriptEngine):  # type: ignore
 
     def __get_augment_methods(self, task: Optional[SpiffTask]) -> Dict[str, Callable]:
         """__get_augment_methods."""
-        tld = current_app.config["THREAD_LOCAL_DATA"]
-
+        tld = current_app.config.get("THREAD_LOCAL_DATA")
         if not hasattr(tld, "process_model_identifier"):
-            raise MissingProcessInfoError(
-                "Could not find process_model_identifier from app config"
-            )
-        if not hasattr(tld, "process_instance_id"):
-            raise MissingProcessInfoError(
-                "Could not find process_instance_id from app config"
-            )
-
+            process_model_identifier = None
+        else:
             process_model_identifier = tld.process_model_identifier
+        if not hasattr(tld, "process_instance_id"):
+            process_instance_id = None
+        else:
             process_instance_id = tld.process_instance_id
         script_attributes_context = ScriptAttributesContext(
             task=task,