npm / @langchain/classic
@langchain/classic
What changed in @langchain/classic 0.3 to 1, from its official release notes, upgrade guides and advisories. Sources checked 2026-10-19.
3 breaking1 security6 new APIs and options1 behavior and defaults5 fixes and other
See which of these apply to your code, ranked, in your agent:
npx @unstale/cli init@langchain/classic 113 changes
Breaking changes 3
The Fireworks provider was extracted into a standalone provider package.
A standalone Perplexity provider package was added.
Together AI was migrated into a provider package.
New APIs and options 6
LangChainTracer now supports explicitly setting an agent address.
Adds the aws alias to MODEL_PROVIDER_CONFIG so hub/node can auto-detect ChatBedrockConverse from Python-serialized prompts.
Accepts an optional modelProvider parameter for direct config lookup, avoiding className collisions when multiple providers share a class name.
Adds support for Aurora Postgres DataSource.
Prompt pulling now supports secrets.
Prompt pulling now supports secretsFromEnv, allowing secrets to be supplied from environment variables.
Behavior and default changes 1
Project and address destinations are inherited together, and default destination resolution is delegated to the LangSmith SDK.
Fixes and other changes 3
Prevents local file corruption when using LocalFileStore.
Avoids long-lived abort signals.
Fixes handling of required fields from nested schemas.
@langchain/classic 0.33 changes
Security 1
A fix was made for CVE-2025-12735.
Fixes and other changes 2
node-gyp was added for Vercel builds.
The default temperature option for v0/anthropic was fixed.