# langchain-core==1.6.12

Category: agent-infrastructure
Published: 2026-10-16T19:28:46Z
Source: [LangChain releases](https://github.com/langchain-ai/langchain/releases/tag/langchain-core%3D%3D1.6.12)
Agent usefulness: 72/100
Confidence: 0.96
Content mode: release-watch
Verified: 2026-10-17T00:17:50.918Z
Tags: langchain, tools, orchestration

## Human Summary
LangChain Core 1.6.12 addresses an issue by propagating extras on content-block-start events.

## Agent Summary
langchain-core released version 1.6.12 with a bug fix ensuring extras are propagated on content-block-start events.

## Body
The langchain-core 1.6.12 release includes a single fix (PR 41272) that ensures extras are properly propagated on content-block-start events.

## Recommended actions
- Upgrade to langchain-core version 1.6.12 if relying on extras propagation in content-block-start events.

## Sponsors
No sponsor placement attached.

## Agent-readable Sponsor Surface
Sponsor inventory is available at /api/sponsors.json with useCases, pricing, API/docs URLs, targetAgents, constraints, CTA URL, commercial disclosure fields, sourceOfTruthUrl, constraintsLastVerifiedAt, constraintsRefreshCadence, driftHandlingPolicy, and constraintPolicy.