Messages following tool_use blocks must begin with a matching number of tool_result blocks.

[jvjfranca-auramind]

Hi,

Im getting the same issue that was fixed on #389 using ChatBedrockConverse.

An error occurred (validationException) when calling the ConverseStream operation: The model returned the following errors: messages.48: Did not find 1 tool_result block(s) at the beginning of this message. Messages following tool_use blocks must begin with a matching number of tool_result blocks.

Using - langchain-aws 0.2.18

Should I go back to ChatBedrock?

Thanks.

[michaelnchin]

Hi @jvjfranca-auramind, thank you for submitting this issue.

Could you kindly provide a minimal code sample to reproduce this?

[jvjfranca-auramind]

My Bad @michaelnchin its working fine. I'll close the issue. Thanks.

[namanbhatia332]

Hi @michaelnchin, how did you solve the issue?

Getting this:
An error occurred (ValidationException) when calling the Converse operation: The model returned the following errors: messages.10: `tool_use` ids were found without `tool_result` blocks immediately after: tooluse_pUTAHNSlRqK4oSDLJnkZ2g. Each `tool_use` block must have a corresponding `tool_result` block in the next message.

Using langchain-aws==0.2.23

[michaelnchin]

Hi @namanbhatia332, would you happen have a reproducer we can try?

We recently found that a similar bug likely affects ChatBedrock, and a fix should be included in the next release, with the added parsing of tool_result in #495. ChatBedrockConverse is expected to be more resilient, but we would like to know if some adjustment is also needed from Langchain side.

[namanbhatia332]

Hi @michaelnchin, sorry for the late reply. I realized I was invoking ChatBedrock without including the corresponding tool message for the AI message.