OpenAI reasoning models filter includes gpt-5-chat-*

[a-i-joe]

Checked other resources

• This is a bug, not a usage question. For questions, please use the LangChain Forum (https://forum.langchain.com/).
• I added a very descriptive title to this issue.
• I searched the LangChain.js documentation with the integrated search.
• I used the GitHub search to find a similar question and didn't find it.
• I am sure that this is a bug in LangChain.js rather than my code.
• The bug is not resolved by updating to the latest stable version of LangChain (or the specific integration package).

Example Code

new ChatOpenAI({modelName: 'gpt-5-chat-latest' ... })

Error Message and Stack Trace (if applicable)

No response

Description

In the following recently merged PR:
https://github.com/langchain-ai/langchainjs/pull/8646/files

return model && (/^o\d/.test(model) || model.startsWith("gpt-5"));

gpt-5-chat-latest is not a reasoning model.

Could replace with return model && (/^o\d/.test(model) || (model.startsWith("gpt-5") && !model.startsWith("gpt-5-chat")));

System Info

irrelevant