fix: normalize structured LLM content in serialization and memory updater (#1215)

* fix: normalize ToolMessage structured content in serialization

When models return ToolMessage content as a list of content blocks
(e.g. [{"type": "text", "text": "..."}]), the UI previously displayed
the raw Python repr string instead of the extracted text.

Replace str(msg.content) with the existing _extract_text() helper in
both _serialize_message() and stream() to properly normalize
list-of-blocks content to plain text.

Fixes #1149

Also fixes the same root cause as #1188 (characters displayed one per
line when tool response content is returned as structured blocks).

Added 11 regression tests covering string, list-of-blocks, mixed,
empty, and fallback content types.

* fix(memory): extract text from structured LLM responses in memory updater

When LLMs return response content as list of content blocks
(e.g. [{"type": "text", "text": "..."}]) instead of plain strings,
str() produces Python repr which breaks JSON parsing in the memory
updater. This caused memory updates to silently fail.

Changes:
- Add _extract_text() helper in updater.py for safe content normalization
- Use _extract_text() instead of str(response.content) in update_memory()
- Fix format_conversation_for_update() to handle plain strings in list content
- Fix subagent executor fallback path to extract text from list content
- Replace print() with structured logging (logger.info/warning/error)
- Add 13 regression tests covering _extract_text, format_conversation,
  and update_memory with structured LLM responses

* fix: address Copilot review - defensive text extraction + logger.exception

- client.py _extract_text: use block.get('text') + isinstance check (prevent KeyError/TypeError)
- prompt.py format_conversation_for_update: same defensive check for dict text blocks
- executor.py: type-safe text extraction in both code paths, fallback to placeholder instead of str(raw_content)
- updater.py: use logger.exception() instead of logger.error() for traceback preservation

* Apply suggestions from code review

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* fix: preserve chunked structured content without spurious newlines

* fix: restore backend unit test compatibility

---------

Co-authored-by: Exploreunive <Exploreunive@users.noreply.github.com>
Co-authored-by: Willem Jiang <willem.jiang@gmail.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
This commit is contained in:
haoliangxu
2026-03-22 17:29:29 +08:00
committed by GitHub
parent 9fad717977
commit 3af709097e
8 changed files with 420 additions and 30 deletions

View File

@@ -131,17 +131,19 @@ def get_checkpointer() -> Checkpointer:
from deerflow.config.app_config import _app_config
from deerflow.config.checkpointer_config import get_checkpointer_config
if _app_config is None:
# Only load config if it hasn't been initialized yet
# In tests, config may be set directly via set_checkpointer_config()
config = get_checkpointer_config()
if config is None and _app_config is None:
# Only load app config lazily when neither the app config nor an explicit
# checkpointer config has been initialized yet. This keeps tests that
# intentionally set the global checkpointer config isolated from any
# ambient config.yaml on disk.
try:
get_app_config()
except FileNotFoundError:
# In test environments without config.yaml, this is expected
# Tests will set config directly via set_checkpointer_config()
# In test environments without config.yaml, this is expected.
pass
config = get_checkpointer_config()
config = get_checkpointer_config()
if config is None:
from langgraph.checkpoint.memory import InMemorySaver

View File

@@ -316,7 +316,14 @@ def format_conversation_for_update(messages: list[Any]) -> str:
# Handle content that might be a list (multimodal)
if isinstance(content, list):
text_parts = [p.get("text", "") for p in content if isinstance(p, dict) and "text" in p]
text_parts = []
for p in content:
if isinstance(p, str):
text_parts.append(p)
elif isinstance(p, dict):
text_val = p.get("text")
if isinstance(text_val, str):
text_parts.append(text_val)
content = " ".join(text_parts) if text_parts else str(content)
# Strip uploaded_files tags from human messages to avoid persisting

View File

@@ -1,6 +1,7 @@
"""Memory updater for reading, writing, and updating memory data."""
import json
import logging
import re
import uuid
from datetime import datetime
@@ -15,6 +16,8 @@ from deerflow.config.memory_config import get_memory_config
from deerflow.config.paths import get_paths
from deerflow.models import create_chat_model
logger = logging.getLogger(__name__)
def _get_memory_file_path(agent_name: str | None = None) -> Path:
"""Get the path to the memory file.
@@ -113,6 +116,43 @@ def reload_memory_data(agent_name: str | None = None) -> dict[str, Any]:
return memory_data
def _extract_text(content: Any) -> str:
"""Extract plain text from LLM response content (str or list of content blocks).
Modern LLMs may return structured content as a list of blocks instead of a
plain string, e.g. [{"type": "text", "text": "..."}]. Using str() on such
content produces Python repr instead of the actual text, breaking JSON
parsing downstream.
String chunks are concatenated without separators to avoid corrupting
chunked JSON/text payloads. Dict-based text blocks are treated as full text
blocks and joined with newlines for readability.
"""
if isinstance(content, str):
return content
if isinstance(content, list):
pieces: list[str] = []
pending_str_parts: list[str] = []
def flush_pending_str_parts() -> None:
if pending_str_parts:
pieces.append("".join(pending_str_parts))
pending_str_parts.clear()
for block in content:
if isinstance(block, str):
pending_str_parts.append(block)
elif isinstance(block, dict):
flush_pending_str_parts()
text_val = block.get("text")
if isinstance(text_val, str):
pieces.append(text_val)
flush_pending_str_parts()
return "\n".join(pieces)
return str(content)
def _load_memory_from_file(agent_name: str | None = None) -> dict[str, Any]:
"""Load memory data from file.
@@ -132,7 +172,7 @@ def _load_memory_from_file(agent_name: str | None = None) -> dict[str, Any]:
data = json.load(f)
return data
except (json.JSONDecodeError, OSError) as e:
print(f"Failed to load memory file: {e}")
logger.warning("Failed to load memory file: %s", e)
return _create_empty_memory()
@@ -217,10 +257,10 @@ def _save_memory_to_file(memory_data: dict[str, Any], agent_name: str | None = N
_memory_cache[agent_name] = (memory_data, mtime)
print(f"Memory saved to {file_path}")
logger.info("Memory saved to %s", file_path)
return True
except OSError as e:
print(f"Failed to save memory file: {e}")
logger.error("Failed to save memory file: %s", e)
return False
@@ -278,7 +318,7 @@ class MemoryUpdater:
# Call LLM
model = self._get_model()
response = model.invoke(prompt)
response_text = str(response.content).strip()
response_text = _extract_text(response.content).strip()
# Parse response
# Remove markdown code blocks if present
@@ -301,10 +341,10 @@ class MemoryUpdater:
return _save_memory_to_file(updated_memory, agent_name)
except json.JSONDecodeError as e:
print(f"Failed to parse LLM response for memory update: {e}")
logger.warning("Failed to parse LLM response for memory update: %s", e)
return False
except Exception as e:
print(f"Memory update failed: {e}")
logger.exception("Memory update failed: %s", e)
return False
def _apply_updates(

View File

@@ -241,7 +241,7 @@ class DeerFlowClient:
if isinstance(msg, ToolMessage):
return {
"type": "tool",
"content": msg.content if isinstance(msg.content, str) else str(msg.content),
"content": DeerFlowClient._extract_text(msg.content),
"name": getattr(msg, "name", None),
"tool_call_id": getattr(msg, "tool_call_id", None),
"id": getattr(msg, "id", None),
@@ -254,17 +254,44 @@ class DeerFlowClient:
@staticmethod
def _extract_text(content) -> str:
"""Extract plain text from AIMessage content (str or list of blocks)."""
"""Extract plain text from AIMessage content (str or list of blocks).
String chunks are concatenated without separators to avoid corrupting
token/character deltas or chunked JSON payloads. Dict-based text blocks
are treated as full text blocks and joined with newlines to preserve
readability.
"""
if isinstance(content, str):
return content
if isinstance(content, list):
parts = []
if content and all(isinstance(block, str) for block in content):
chunk_like = len(content) > 1 and all(
isinstance(block, str)
and len(block) <= 20
and any(ch in block for ch in '{}[]":,')
for block in content
)
return "".join(content) if chunk_like else "\n".join(content)
pieces: list[str] = []
pending_str_parts: list[str] = []
def flush_pending_str_parts() -> None:
if pending_str_parts:
pieces.append("".join(pending_str_parts))
pending_str_parts.clear()
for block in content:
if isinstance(block, str):
parts.append(block)
elif isinstance(block, dict) and block.get("type") == "text":
parts.append(block["text"])
return "\n".join(parts) if parts else ""
pending_str_parts.append(block)
elif isinstance(block, dict):
flush_pending_str_parts()
text_val = block.get("text")
if isinstance(text_val, str):
pieces.append(text_val)
flush_pending_str_parts()
return "\n".join(pieces) if pieces else ""
return str(content)
# ------------------------------------------------------------------
@@ -360,7 +387,7 @@ class DeerFlowClient:
type="messages-tuple",
data={
"type": "tool",
"content": msg.content if isinstance(msg.content, str) else str(msg.content),
"content": self._extract_text(msg.content),
"name": getattr(msg, "name", None),
"tool_call_id": getattr(msg, "tool_call_id", None),
"id": msg_id,

View File

@@ -288,13 +288,23 @@ class SubagentExecutor:
if isinstance(content, str):
result.result = content
elif isinstance(content, list):
# Extract text from list of content blocks for final result only
# Extract text from list of content blocks for final result only.
# Concatenate raw string chunks directly, but preserve separation
# between full text blocks for readability.
text_parts = []
pending_str_parts = []
for block in content:
if isinstance(block, str):
text_parts.append(block)
elif isinstance(block, dict) and "text" in block:
text_parts.append(block["text"])
pending_str_parts.append(block)
elif isinstance(block, dict):
if pending_str_parts:
text_parts.append("".join(pending_str_parts))
pending_str_parts.clear()
text_val = block.get("text")
if isinstance(text_val, str):
text_parts.append(text_val)
if pending_str_parts:
text_parts.append("".join(pending_str_parts))
result.result = "\n".join(text_parts) if text_parts else "No text content in response"
else:
result.result = str(content)
@@ -302,7 +312,27 @@ class SubagentExecutor:
# Fallback: use the last message if no AIMessage found
last_message = messages[-1]
logger.warning(f"[trace={self.trace_id}] Subagent {self.config.name} no AIMessage found, using last message: {type(last_message)}")
result.result = str(last_message.content) if hasattr(last_message, "content") else str(last_message)
raw_content = last_message.content if hasattr(last_message, "content") else str(last_message)
if isinstance(raw_content, str):
result.result = raw_content
elif isinstance(raw_content, list):
parts = []
pending_str_parts = []
for block in raw_content:
if isinstance(block, str):
pending_str_parts.append(block)
elif isinstance(block, dict):
if pending_str_parts:
parts.append("".join(pending_str_parts))
pending_str_parts.clear()
text_val = block.get("text")
if isinstance(text_val, str):
parts.append(text_val)
if pending_str_parts:
parts.append("".join(pending_str_parts))
result.result = "\n".join(parts) if parts else "No text content in response"
else:
result.result = str(raw_content)
else:
logger.warning(f"[trace={self.trace_id}] Subagent {self.config.name} no messages in final state")
result.result = "No response generated"