Issues

• core: mustache dotted name inside a section falls back to an outer scope and renders unrelated data

  bugcoreexternal
  Bug

  langchain-ai/langchain#41281 · Filter by author kakiuwang-ui opened on Oct 17, 2026

• RouterRunnable batch ignores return_exceptions=True for unknown routes

  bugcoreexternal
  Bug

  langchain-ai/langchain#41280 · Filter by author AryanRG opened on Oct 16, 2026

• core: batch/abatch are typed list[Output] even with return_exceptions=True

  bugcoreinternal
  langchain-ai/langchain#41276 · Filter by author ramon-langchain opened on Oct 16, 2026
  1

• trim_messages(strategy="last", allow_partial=True) can return messages that exceed max_tokens

  bugcoreexternal
  Bug

  langchain-ai/langchain#41259 · Filter by author djedi-knight opened on Oct 15, 2026
  1

• langchain: add reversible pseudonymize strategy and composite context detectors to PIIMiddleware

  externalfeature requestlangchain
  Feature

  langchain-ai/langchain#41256 · Filter by author ghanikhalid opened on Oct 15, 2026
  1

• merge_message_runs promotes invalid tool calls to valid tool calls

  bugcoreexternal
  Bug

  langchain-ai/langchain#41254 · Filter by author master1018 opened on Oct 15, 2026
  4

• Restore Codex sandbox CLI compatibility and scope native Windows shell support

  externalfeature requestlangchain
  Feature

  langchain-ai/langchain#41252 · Filter by author ChampionsZhang opened on Oct 15, 2026
  1

• trim_messages double-counts request-level token costs and drops messages that fit

  bugcoreexternal
  Bug

  langchain-ai/langchain#41250 · Filter by author ys0v9 opened on Oct 15, 2026
  1

• Map reasoning effort levels from models.dev

  bugexternallangchain
  Bug

  langchain-ai/langchain#41248 · Filter by author Vorpalin opened on Oct 14, 2026
  2

• ClearToolUsesEdit fails to clear tool inputs in content blocks

  bugexternallangchain
  Bug

  langchain-ai/langchain#41238 · Filter by author UnZHGPPT opened on Oct 14, 2026
  3

• openai: streaming drops the assistant audio payload, so a streamed audio turn cannot be continued

  bugexternalopenai
  Bug

  langchain-ai/langchain#41237 · Filter by author kodurd opened on Oct 14, 2026
  3

• core: expose the prompt template to chat model and LLM callbacks so tracers can attach it to GenAI spans

  coreexternalfeature request
  Feature

  langchain-ai/langchain#41235 · Filter by author theshubhamgoel opened on Oct 13, 2026

• ShellSession.execute: Command include "exit N" can lead to a TimeOut

  bugexternallangchain
  Bug

  langchain-ai/langchain#41228 · Filter by author master1018 opened on Oct 13, 2026
  5

• A text-plain content block with inline text is rejected by the Bedrock, Gemini and OpenAI converters

  bugcoreexternalopenai
  Bug

  langchain-ai/langchain#41227 · Filter by author awg66 opened on Oct 12, 2026
  3

• langchain-typesafe: NaN/Infinity in state or criteria crash invoke with uncaught ValueError from httpx2 internals

  bugexternaltypesafe
  Bug

  langchain-ai/langchain#41214 · Filter by author kittimzhe opened on Oct 12, 2026
  2

• langchain-core: add a beta BaseDecisionModel interface for bounded judgments

  coreexternalinvestigateopenaistandard-teststypesafe
  langchain-ai/langchain#41193 · Filter by author teenaxta opened on Oct 10, 2026
  3

• perf(text-splitters): reduce repeated list copying during chunk eviction

  externalfeature requesttext-splitters
  Feature

  langchain-ai/langchain#41191 · Filter by author mowne67 opened on Oct 10, 2026
  1

• text-splitters: add_start_index returns an earlier duplicate's position when a chunk is shorter than chunk_overlap

  bugexternaltext-splitters
  Bug

  langchain-ai/langchain#41190 · Filter by author SANJANAKUMARI83 opened on Oct 10, 2026
  3

• HTMLSemanticPreservingSplitter corrupts text containing the literal PRESERVED_<n> (in-band placeholder) and _reinsert_preserved_elements is O(chunks x placeholders)

  bugexternaltext-splitters
  Bug

  langchain-ai/langchain#41186 · Filter by author moneebullah25 opened on Oct 9, 2026
  3

• HTMLSemanticPreservingSplitter(allowlist_tags=[...]) returns no documents (and drops preserved media)

  bugexternaltext-splitters
  Bug

  langchain-ai/langchain#41185 · Filter by author moneebullah25 opened on Oct 9, 2026
  4

• MarkdownTextSplitter and LatexTextSplitter never split on headings/sections (separators are regex-escaped)

  bugexternaltext-splitters
  Bug

  langchain-ai/langchain#41184 · Filter by author moneebullah25 opened on Oct 9, 2026
  6

• [RFC] Feature: Add Runnable.with_rescue() / RunnableRescue for inline step recovery in LCEL

  externalfeature requestlangchain
  Feature

  langchain-ai/langchain#41179 · Filter by author powerofaisinstudy-debug opened on Oct 9, 2026
  5

• sanitize_for_postgres docstring examples pass literal escapes instead of NUL characters

  bugcoreexternal
  Bug

  langchain-ai/langchain#41177 · Filter by author normaltank opened on Oct 9, 2026
  2

• core: mustache ChatPromptTemplate input schema types nested variables as str, so as_tool rejects valid input

  bugcoreexternal
  Bug

  langchain-ai/langchain#41169 · Filter by author sahil-mangla opened on Oct 9, 2026
  2

• count_tokens_approximately omits tool calls when AIMessage content is a list

  bugcoreexternal
  Bug

  langchain-ai/langchain#41166 · Filter by author bnkaiteam opened on Oct 9, 2026
  4