React Agent runtime error: no Final Answer output but got "I am thinking about how to help you"

[Sakura4036]

Self Checks

• [x] This is only for bug report, if you would like to ask a question, please head to Discussions.
• [x] I have searched for existing issues search for existing issues, including closed ones.
• [x] I confirm that I am using English to submit this report (我已阅读并同意 Language Policy).
• [x] [FOR CHINESE USERS] 请务必使用英文提交 Issue，否则会被关闭。谢谢！:)
• [x] Please do not modify this template :) and fill in all the required fields.

Dify version

1.3.1

Cloud or Self Hosted

Self Hosted (Source)

Steps to reproduce

1. create a workflow app
2. add agent node, with react strategy , select deepseek-v3 model, set max_steps = 10
3. add tavily search and extract tools
4. write system and user prompt
5. run this app

✔️ Expected Behavior

agent works fine, use tavily tools, return Final Answer.

❌ Actual Behavior

After testing, React agent often experiences a lack of output after more than 3 iterations, resulting in the program returning "I am thinking about how to help you", or only having thought output without action_input, action_name, etc., which means there is no Final Answer output.

• app
• agent
• error
• no error
• no error

[dosubot[bot]]

To resolve the issue where the React Agent runtime error results in no Final Answer output, but instead returns "I am thinking about how to help you" after more than 3 iterations, ensure that the agent is correctly identifying and processing the "Final Answer" action. The agent checks for a "Final Answer" action and processes it accordingly in the cot_agent_runner.py file. Make sure the action name is set to "Final Answer" and the action input is properly formatted ^[1].

Additionally, verify that the agent's output adheres to the specific format for actions, using a JSON blob to specify the tool and input, as outlined in the multi_dataset_react_route.py file ^[2]. The format should be:

{
  "action": "Final Answer",
  "action_input": "Final response to human"
}

Ensure the agent's output is correctly structured and recognized by the system. The StructuredChatOutputParser in structured_chat.py uses regular expressions to identify actions within the text and checks for the "Final Answer" action ^[3]. Make sure the output from the agent is correctly formatted to be parsed by this logic. If the output is not being parsed correctly, it may result in the agent not recognizing the "Final Answer" and continuing to iterate.

To continue talking to Dosu, mention @dosu.

---

^{Help Dosu learn! Give it feedback: Great Response | Irrelevant Answer | Incorrect Sources | Too Verbose | Hallucination | Bug Report | Other}

[viereck-lan]

I have the same malfunction.

[ctruk]

I have the same problem. When will it be fixed?

[witomalik]

I have the same issue

[rosswj]

After configuring the ReactAgent with MCP, the execution success rate is very low. We hope developers can refer to this implementation for guidance:

ModelScope MCP Playground

[01RK]

It's frustrating, I completely failed after I called the remote playwright.

[SHENRUIYANG]

To resolve the issue where the React Agent runtime error results in no Final Answer output, but instead returns "I am thinking about how to help you" after more than 3 iterations, ensure that the agent is correctly identifying and processing the "Final Answer" action. The agent checks for a "Final Answer" action and processes it accordingly in the cot_agent_runner.py file. Make sure the action name is set to "Final Answer" and the action input is properly formatted [1].

Additionally, verify that the agent's output adheres to the specific format for actions, using a JSON blob to specify the tool and input, as outlined in the multi_dataset_react_route.py file [2]. The format should be:

{
  "action": "Final Answer",
  "action_input": "Final response to human"
}

Ensure the agent's output is correctly structured and recognized by the system. The StructuredChatOutputParser in structured_chat.py uses regular expressions to identify actions within the text and checks for the "Final Answer" action [3]. Make sure the output from the agent is correctly formatted to be parsed by this logic. If the output is not being parsed correctly, it may result in the agent not recognizing the "Final Answer" and continuing to iterate.

To continue talking to Dosu, mention @dosu.

Help Dosu learn! Give it feedback: Great Response | Irrelevant Answer | Incorrect Sources | Too Verbose | Hallucination | Bug Report | Other

I don't understand what you mean. Using prompt?

[SHENRUIYANG]

My response is like this:

[coopercoder]

I have the same issue

[ayushranjan619]

This is a significant issue with agent block. Has anyone found a solution to this?

[hxt365]

Upgrading the plugin daemon to the latest version helps

[juniorsereno]

The agent becomes completely unusable with this problem; now with the MCP tool, it no longer responds with anything other than "I am thinking about how to help you."

[Nov1c444]

The agent becomes completely unusable with this problem; now with the MCP tool, it no longer responds with anything other than "I am thinking about how to help you."

Would you be able to share a DSL that reproduces the issue? I'm having trouble replicating it from your description alone.

[fyxemmmm]

same error, i found that gemini has this error, but deepseekv3 and chatgpt4.1 are correct. I consider the model has problem?

just the react has this error, when i switch to function calling, gemini can show correct. But function calling has a ugly display because it will take all the consider to me, i just want the result, you know.

[DullJZ]

I am facing the problem with model Kimi-K2-Instruct as well.

The issue may occur in /api/core/agent/cot_agent_runner.py at line 160:

scratchpad.thought = scratchpad.thought.strip() or "I am thinking about how to help you"

and at line 388

current_scratchpad = AgentScratchpadUnit(
    agent_response=message.content,
    thought=message.content or "I am thinking about how to help you",
    action_str="",
    action=None,
    observation=None,
)

Guess: When LLM does not return data in a fixed format, the system parsing field fails and is automatically replaced with the string "I am thinking about how to help you".

In addition, I found that after Dify has returned "I am thinking about how to help you", the system is still calling my MCP server in the background, which means that ReAct has not actually stopped.

Possible workaround: After the parsing field fails, do not simply replace the string, but try this Action again

[yangyf520]

I have the same issue，with open ai LLM

[faithererer]

一样的问题，使用gemini-2.0-flash，但是2.5 flash正常

[YoWhatever]

same issue

[dosubot[bot]]

Hi, @Sakura4036. I'm Dosu, and I'm helping the Dify team manage their backlog and am marking this issue as stale.

Issue Summary:

• You reported that in Dify v1.3.1 self-hosted, the React agent with deepseek-v3 model repeatedly returns "I am thinking about how to help you" instead of a "Final Answer."
• Other users, including viereck-lan and ctruk, have confirmed similar issues affecting multiple models like Kimi-K2-Instruct and OpenAI LLM.
• Suggestions were made to ensure the agent's output strictly follows the expected JSON format and to handle parsing failures more gracefully by retrying actions.
• The issue remains unresolved, and no definitive fix or workaround has been implemented yet.

Next Steps:

• Please let me know if this issue is still relevant with the latest version of Dify by commenting here to keep the discussion open.
• Otherwise, this issue will be automatically closed in 15 days.

Thank you for your understanding and contribution!

[chrisesposito92]

I am having the same issue with all Gemini models