[bedrock] Error: ValidationException: A conversation must start with a user message. Try again with a conversation that starts with a user message.

[luckylhb90]

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Dify version

0.10.2

Cloud or Self Hosted

Self Hosted (Source)

Steps to reproduce

1. When we use sonnet3.5 with memory enabled, this error is always reported when we call it.

[bedrock] Error: ValidationException: A conversation must start with a user message. Try again with a conversation that starts with a user message.

2. I analyzed the code and guessed that it might have something to do with checking tokens here. For the other models, I didn't think there was a problem, but for sonnet, if we removed a prompt, it would cause this error.

3. I try to modify the configuration of the model, but again I get input token overrun issues. context_size: 20000000

Is there any relevant experience you can provide for our reference?

✔️ Expected Behavior

Even if the memory function is enabled, users will not be affected.

❌ Actual Behavior

Always get the following error：