feat: lazy import chromadb

* fix: handle HumanFeedbackPending in flow error management

Updated the flow error handling to treat HumanFeedbackPending as expected control flow rather than an error. This change ensures that the flow can appropriately manage human feedback scenarios without signaling an error, improving the robustness of the flow execution.

* fix: improve error handling for HumanFeedbackPending in flow execution

Refined the flow error management to emit a paused event for HumanFeedbackPending exceptions instead of treating them as failures. This enhancement allows the flow to better manage human feedback scenarios, ensuring that the execution state is preserved and appropriately handled without signaling an error. Regular failure events are still emitted for other exceptions, maintaining robust error reporting.

lib/crewai/src/crewai/flow/flow.py

@@ -1203,7 +1203,13 @@ class Flow(Generic[T], metaclass=FlowMeta):
                     result = self.kickoff(inputs=inputs)
                     result_holder.append(result)
                 except Exception as e:
-                    signal_error(state, e)
+                    # HumanFeedbackPending is expected control flow, not an error
+                    from crewai.flow.async_feedback.types import HumanFeedbackPending
+
+                    if isinstance(e, HumanFeedbackPending):
+                        result_holder.append(e)
+                    else:
+                        signal_error(state, e)
                 finally:
                     self.stream = True
                     signal_end(state)
@@ -1258,7 +1264,13 @@ class Flow(Generic[T], metaclass=FlowMeta):
                     result = await self.kickoff_async(inputs=inputs)
                     result_holder.append(result)
                 except Exception as e:
-                    signal_error(state, e, is_async=True)
+                    # HumanFeedbackPending is expected control flow, not an error
+                    from crewai.flow.async_feedback.types import HumanFeedbackPending
+
+                    if isinstance(e, HumanFeedbackPending):
+                        result_holder.append(e)
+                    else:
+                        signal_error(state, e, is_async=True)
                 finally:
                     self.stream = True
                     signal_end(state, is_async=True)
@@ -1590,29 +1602,45 @@ class Flow(Generic[T], metaclass=FlowMeta):
 
             return result
         except Exception as e:
-            if not self.suppress_flow_events:
-                # Check if this is a HumanFeedbackPending exception (paused, not failed)
-                from crewai.flow.async_feedback.types import HumanFeedbackPending
+            # Check if this is a HumanFeedbackPending exception (paused, not failed)
+            from crewai.flow.async_feedback.types import HumanFeedbackPending
 
-                if isinstance(e, HumanFeedbackPending):
-                    # Auto-save pending feedback (create default persistence if needed)
-                    if self._persistence is None:
-                        from crewai.flow.persistence import SQLiteFlowPersistence
+            if isinstance(e, HumanFeedbackPending):
+                # Auto-save pending feedback (create default persistence if needed)
+                if self._persistence is None:
+                    from crewai.flow.persistence import SQLiteFlowPersistence
 
-                        self._persistence = SQLiteFlowPersistence()
+                    self._persistence = SQLiteFlowPersistence()
 
-            # Regular failure
-            future = crewai_event_bus.emit(
-                self,
-                MethodExecutionFailedEvent(
-                    type="method_execution_failed",
-                    method_name=method_name,
-                    flow_name=self.name or self.__class__.__name__,
-                    error=e,
-                ),
-            )
-            if future:
-                self._event_futures.append(future)
+                # Emit paused event (not failed)
+                if not self.suppress_flow_events:
+                    future = crewai_event_bus.emit(
+                        self,
+                        MethodExecutionPausedEvent(
+                            type="method_execution_paused",
+                            method_name=method_name,
+                            flow_name=self.name or self.__class__.__name__,
+                            state=self._copy_and_serialize_state(),
+                            flow_id=e.context.flow_id,
+                            message=e.context.message,
+                            emit=e.context.emit,
+                        ),
+                    )
+                    if future:
+                        self._event_futures.append(future)
+            elif not self.suppress_flow_events:
+                # Regular failure - emit failed event
+                future = crewai_event_bus.emit(
+                    self,
+                    MethodExecutionFailedEvent(
+                        type="method_execution_failed",
+                        method_name=method_name,
+                        flow_name=self.name or self.__class__.__name__,
+                        error=e,
+                    ),
+                )
+                if future:
+                    self._event_futures.append(future)
             raise e
 
     def _copy_and_serialize_state(self) -> dict[str, Any]:

lib/crewai/src/crewai/knowledge/storage/knowledge_storage.py

@@ -1,21 +1,24 @@
+from __future__ import annotations
+
 import logging
 import traceback
-from typing import Any, cast
+from typing import TYPE_CHECKING, Any, cast
 import warnings
 
 from crewai.knowledge.storage.base_knowledge_storage import BaseKnowledgeStorage
-from crewai.rag.chromadb.config import ChromaDBConfig
-from crewai.rag.chromadb.types import ChromaEmbeddingFunctionWrapper
 from crewai.rag.config.utils import get_rag_client
 from crewai.rag.core.base_client import BaseClient
 from crewai.rag.core.base_embeddings_provider import BaseEmbeddingsProvider
 from crewai.rag.embeddings.factory import build_embedder
-from crewai.rag.embeddings.types import ProviderSpec
 from crewai.rag.factory import create_client
 from crewai.rag.types import BaseRecord, SearchResult
 from crewai.utilities.logger import Logger
 
 
+if TYPE_CHECKING:
+    from crewai.rag.embeddings.types import ProviderSpec
+
+
 class KnowledgeStorage(BaseKnowledgeStorage):
     """
     Extends Storage to handle embeddings for memory entries, improving
@@ -30,6 +33,9 @@ class KnowledgeStorage(BaseKnowledgeStorage):
         | None = None,
         collection_name: str | None = None,
     ) -> None:
+        from crewai.rag.chromadb.config import ChromaDBConfig
+        from crewai.rag.chromadb.types import ChromaEmbeddingFunctionWrapper
+
         self.collection_name = collection_name
         self._client: BaseClient | None = None
 

lib/crewai/src/crewai/memory/storage/rag_storage.py

@@ -5,8 +5,6 @@ import traceback
 from typing import TYPE_CHECKING, Any, cast
 import warnings
 
-from crewai.rag.chromadb.config import ChromaDBConfig
-from crewai.rag.chromadb.types import ChromaEmbeddingFunctionWrapper
 from crewai.rag.config.utils import get_rag_client
 from crewai.rag.embeddings.factory import build_embedder
 from crewai.rag.factory import create_client
@@ -37,6 +35,9 @@ class RAGStorage(BaseRAGStorage):
         crew: Crew | None = None,
         path: str | None = None,
     ) -> None:
+        from crewai.rag.chromadb.config import ChromaDBConfig
+        from crewai.rag.chromadb.types import ChromaEmbeddingFunctionWrapper
+
         super().__init__(type, allow_reset, embedder_config, crew)
         crew_agents = crew.agents if crew else []
         sanitized_roles = [self._sanitize_role(agent.role) for agent in crew_agents]

lib/crewai/src/crewai/rag/chromadb/config.py

@@ -1,11 +1,12 @@
 """ChromaDB configuration model."""
 
+from __future__ import annotations
+
 from dataclasses import field
 import os
-from typing import Literal, cast
+from typing import TYPE_CHECKING, Literal, cast
 import warnings
 
-from chromadb.config import Settings
 from pydantic.dataclasses import dataclass as pyd_dataclass
 
 from crewai.rag.chromadb.constants import (
@@ -13,10 +14,15 @@ from crewai.rag.chromadb.constants import (
     DEFAULT_STORAGE_PATH,
     DEFAULT_TENANT,
 )
-from crewai.rag.chromadb.types import ChromaEmbeddingFunctionWrapper
 from crewai.rag.config.base import BaseRagConfig
 
 
+if TYPE_CHECKING:
+    from chromadb.config import Settings
+
+    from crewai.rag.chromadb.types import ChromaEmbeddingFunctionWrapper
+
+
 warnings.filterwarnings(
     "ignore",
     message=".*Mixing V1 models and V2 models.*",
@@ -37,6 +43,8 @@ def _default_settings() -> Settings:
     Returns:
         Settings with persistent storage and reset enabled.
     """
+    from chromadb.config import Settings
+
     return Settings(
         persist_directory=DEFAULT_STORAGE_PATH,
         allow_reset=True,
@@ -54,6 +62,8 @@ def _default_embedding_function() -> ChromaEmbeddingFunctionWrapper:
         OpenAIEmbeddingFunction,
     )
 
+    from crewai.rag.chromadb.types import ChromaEmbeddingFunctionWrapper
+
     return cast(
         ChromaEmbeddingFunctionWrapper,
         OpenAIEmbeddingFunction(

lib/crewai/src/crewai/rag/chromadb/factory.py

@@ -1,13 +1,18 @@
 """Factory functions for creating ChromaDB clients."""
 
+from __future__ import annotations
+
 from hashlib import md5
 import os
+from typing import TYPE_CHECKING
 
 from chromadb import PersistentClient
 import portalocker
 
-from crewai.rag.chromadb.client import ChromaDBClient
-from crewai.rag.chromadb.config import ChromaDBConfig
+
+if TYPE_CHECKING:
+    from crewai.rag.chromadb.client import ChromaDBClient
+    from crewai.rag.chromadb.config import ChromaDBConfig
 
 
 def create_client(config: ChromaDBConfig) -> ChromaDBClient:
@@ -22,6 +27,7 @@ def create_client(config: ChromaDBConfig) -> ChromaDBClient:
     Notes:
         Need to update to use chromadb.Client to support more client types in the near future.
     """
+    from crewai.rag.chromadb.client import ChromaDBClient
 
     persist_dir = config.settings.persist_directory
     os.makedirs(persist_dir, exist_ok=True)