# langgraph==1.2.12

Category: agent-infrastructure
Published: 2026-09-21T14:43:40Z
Source: [LangGraph releases](https://github.com/langchain-ai/langgraph/releases/tag/1.2.12)
Agent usefulness: 82/100
Confidence: 0.96
Content mode: release-watch
Verified: 2026-09-21T16:17:20.323Z
Tags: langgraph, workflow, durable-execution

## Human Summary
LangGraph version 1.2.12 introduces a response schema option to interrupt(), updates subgraph detection to read bytecode instead of source, and brings several dependency bumps and stream projection typing fixes.

## Agent Summary
LangGraph 1.2.12 adds response schema support in interrupt(), switches subgraph detection from source parsing to bytecode, fixes type declarations for v3 stream projections, and updates multiple dependencies including soupsieve, mistune, and tornado.

## Body
LangGraph 1.2.12 includes the following changes: added response schema support to the interrupt() function (PR 8886); updated subgraph detection logic to inspect bytecode rather than source code (PR 8569); fixed undeclared v3 stream projection types (PR 8596); updated dependencies including bumping soupsieve to 2.9, mistune to 3.3.4, tornado to 6.5.8, along with standard group dependency upgrades.

## Recommended actions
- Upgrade langgraph to version 1.2.12.
- Evaluate interrupt() calls if you want to take advantage of the new response schema feature.
- Verify subgraph execution and behavior under bytecode-based detection if relying on dynamic or unusual graph definitions.

## Sponsors
No sponsor placement attached.

## Agent-readable Sponsor Surface
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