fix(langchain): minor docs fix on modelFallbackMiddleware (#9392)

christian-bromann · web-flow · commit 87f120b2d8ca · 2025-11-13T10:16:38.000-08:00
diff --git a/libs/langchain/src/agents/middleware/modelFallback.ts b/libs/langchain/src/agents/middleware/modelFallback.ts
@@ -15,10 +15,10 @@ import { createMiddleware } from "../middleware.js";
  * import { createAgent, modelFallbackMiddleware } from "langchain";
  *
  * // Create middleware with fallback models (not including primary)
- * const fallback = modelFallbackMiddleware({
+ * const fallback = modelFallbackMiddleware(
  *   "openai:gpt-4o-mini",  // First fallback
  *   "anthropic:claude-sonnet-4-5-20250929",  // Second fallback
- * });
+ * );
  *
  * const agent = createAgent({
  *   model: "openai:gpt-4o",  // Primary model

Original file line number	Diff line number	Diff line change
`@@ -15,10 +15,10 @@ import { createMiddleware } from "../middleware.js";`
`15`	`15`	`* import { createAgent, modelFallbackMiddleware } from "langchain";`
`16`	`16`	`*`
`17`	`17`	`* // Create middleware with fallback models (not including primary)`
`18`		`- * const fallback = modelFallbackMiddleware({`
	`18`	`+ * const fallback = modelFallbackMiddleware(`
`19`	`19`	`* "openai:gpt-4o-mini", // First fallback`
`20`	`20`	`* "anthropic:claude-sonnet-4-5-20250929", // Second fallback`
`21`		`- * });`
	`21`	`+ * );`
`22`	`22`	`*`
`23`	`23`	`* const agent = createAgent({`
`24`	`24`	`* model: "openai:gpt-4o", // Primary model`