Issues

• Feature: HumanInTheLoopMiddleware for Agent workflows

  externalfeature requestlangchain
  Feature

  langchain-ai/langchain#41612 · Filter by author kaseraaryan5-star opened on Nov 1, 2026

• langchain-deepseek: list-form tool results are sent as ASCII-escaped JSON, inflating non-English tool output ~5x

  bugdeepseekexternal
  Bug

  langchain-ai/langchain#41609 · Filter by author ChengJu1 opened on Nov 1, 2026
  2

• core: parse_json_markdown returns the wrong value for a json5 fence and fails on other fence tags

  bugcoreexternal
  Bug

  langchain-ai/langchain#41607 · Filter by author kkm121 opened on Oct 31, 2026
  1

• with_structured_output with dict/JSON schema silently returns None on unrecognized tool name

  bugcoreexternal
  Bug

  langchain-ai/langchain#41605 · Filter by author shadowmodder opened on Oct 31, 2026
  4

• mistralai: the text of an assistant message that also has tool calls is dropped from the conversation history

  bugexternalmistralai
  Bug

  langchain-ai/langchain#41603 · Filter by author Jingyi-A-Chen opened on Oct 31, 2026
  1

• convert_to_messages raises JSONDecodeError on OpenAI-format tool calls with empty-string arguments

  bugcoreexternal
  Bug

  langchain-ai/langchain#41601 · Filter by author sahil-mangla opened on Oct 31, 2026
  2

• langchain-anthropic: AnthropicLLM default model claude-sonnet-4-5 retires on 2026-11-30

  anthropicbugexternal
  Bug

  langchain-ai/langchain#41599 · Filter by author pcbeingused333 opened on Oct 31, 2026
  1

• core: merge_message_runs turns two OpenAI developer messages into role 'developerdeveloper'

  bugcoreexternal
  Bug

  langchain-ai/langchain#41593 · Filter by author adityasingh2400 opened on Oct 31, 2026
  4

• EarlyReturnMiddleware: dynamically short-circuit the last LLM call of an agentic loop invocation

  externalfeature requestlangchain
  Feature

  langchain-ai/langchain#41583 · Filter by author eric-burel opened on Oct 30, 2026

• HumanInTheLoopMiddleware: record the human decision on the resulting ToolMessage

  externalfeature requestlangchain
  Feature

  langchain-ai/langchain#41569 · Filter by author 5enxia opened on Oct 30, 2026
  2

• XMLOutputParser.transform() has quadratic runtime on non-XML streaming prefixes

  bugcoreexternal
  Bug

  langchain-ai/langchain#41560 · Filter by author Zam-M opened on Oct 29, 2026
  5

• ChatHuggingFace not working with structured output

  bugexternalhuggingface
  Bug

  langchain-ai/langchain#41557 · Filter by author Sbrjt opened on Oct 29, 2026
  2

• parse_partial_json drops a key while a streamed chunk ends inside a \uXXXX escape

  bugcoreexternal
  Bug

  langchain-ai/langchain#41545 · Filter by author canblmz1 opened on Oct 28, 2026
  2

• langchain-openrouter: support OAuth PKCE authentication

  feature requestinternalopenrouter
  Feature

  langchain-ai/langchain#41541 · Filter by author open-swe opened on Oct 28, 2026
  

• InMemoryVectorStore accepts an empty ID list for nonempty documents

  bugcoreexternal
  Bug

  langchain-ai/langchain#41534 · Filter by author AdemGhalleb opened on Oct 27, 2026
  6

• Chroma.similarity_search_by_image_with_relevance_score passes nested list as query embedding (missing [0] unpack)

  bugchromaexternal
  Bug

  langchain-ai/langchain#41528 · Filter by author ryan1234814 opened on Oct 27, 2026
  6

• Tool config: RunnableConfig parameter receives the parent config instead of the child config, so nested runnables are traced as siblings of the tool run

  bugcoreexternal
  Bug

  langchain-ai/langchain#41523 · Filter by author Bear0117 opened on Oct 27, 2026
  4

• HumanInTheLoopMiddleware (batched mode) silently drops a reviewer's edit and runs the original tool call when the tool call id is an empty string

  bugexternallangchain
  Bug

  langchain-ai/langchain#41522 · Filter by author Bear0117 opened on Oct 27, 2026
  2

• huggingface: HuggingFaceEndpointEmbeddings still shows huggingfacehub_api_token in plaintext in repr

  bughuggingface
  Bug

  langchain-ai/langchain#41518 · Filter by author JessYanCoding opened on Oct 27, 2026
  2

• InjectedToolCallId is never injected when args_schema is a JSON schema dict (TypeError: missing 1 required positional argument)

  bugcoreexternal
  Bug

  langchain-ai/langchain#41517 · Filter by author Bear0117 opened on Oct 27, 2026
  3

• Multi-server MCPConfig tools all report MCPRouter as their server

  bugexternallangchain
  Bug

  langchain-ai/langchain#41507 · Filter by author keenborder786 opened on Oct 26, 2026
  1

• TextSplitter._merge_splits does not warn when the last chunk exceeds chunk_size

  bugexternaltext-splitters
  Bug

  langchain-ai/langchain#41498 · Filter by author J4BEZ opened on Oct 26, 2026
  2

• mistralai: an error event inside a chat stream is silently dropped, and the truncated output is returned as a successful response

  bugexternalmistralai
  Bug

  langchain-ai/langchain#41490 · Filter by author Jingyi-A-Chen opened on Oct 26, 2026
  2

• create_agent ends mixed batches early when a non-direct tool is registered at runtime

  bugexternallangchain
  Bug

  langchain-ai/langchain#41480 · Filter by author Ricky-RC opened on Oct 25, 2026
  2

• _generate_response_from_error leaves an unawaited coroutine when the error's response comes from an async HTTP client

  bugcoreexternal
  Bug

  langchain-ai/langchain#41471 · Filter by author popotam opened on Oct 25, 2026
  2