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Problems.

Trouble with LangChain core

LLM apps3 posts from 2 people2d active+00 posts in the last 7 days, 0 the 7 days before (fading)

Posts per day

Posts per day3 posts, Aug 27 to Sep 25

The posts behind it

3, newest first
PostDate
core: check_valid_template raises ValueError for mustache template_format### Description `check_valid_template` fails when `template_format="mustache"` even though `DEFAULT_FORMATTER_MAPPING` supports mustache templates and `PromptTemplate(..., template_format="mustache")` is valid. ### Reproduction ### Error ### Proposed Fix 1. Add...langchain-ai/langchainYeshwanthRajSelvarajAug 284 weeks ago
core: `AIMessage.content_blocks` mutates the original text block when attaching Google grounding citations### Submission checklist - [x] This is a bug, not a usage question. - [x] I added a clear and descriptive title that summarizes this issue. - [x] I used the GitHub search to find a similar question and didn't find it. - [x] I am sure that this is a bug in LangChain rather than...langchain-ai/langchainrevanth-045Aug 274 weeks ago
core: `AIMessage.content_blocks` mutates the original text block when attaching Google grounding citations### Submission checklist - [x] This is a bug, not a usage question. - [x] I added a clear and descriptive title that summarizes this issue. - [x] I used the GitHub search to find a similar question and didn't find it. - [x] I am sure that this is a bug in LangChain rather than...langchain-ai/langchainrevanth-045Aug 274 weeks ago

Companies and products named

Company or productPosts naming it
LangChain3
GitHub2
About this problem

Evidence

3 posts from 2 people in 1 place, about 3 a week over 2 days. Mostly on langchain-ai/langchain. Tools named alongside: GitHub.

Frustration Frustration 0 of 3· Seen on GitHub issues

How it was grouped

Posts about LangChain with no known issue, sharing the word "core". First post Aug 27, 2026, latest Aug 28, 2026. Corroborated: 3 or more posts from 2 or more people or places. Method

History

  • 2026-09-25 Added: Trouble with LangChain core (3 posts)

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