core[patch]: Add isZodSchema to core utils

langchain-core/.gitignore

@@ -194,6 +194,10 @@ utils/beta_warning.cjs
 utils/beta_warning.js
 utils/beta_warning.d.ts
 utils/beta_warning.d.cts
+utils/is_zod_schema.cjs
+utils/is_zod_schema.js
+utils/is_zod_schema.d.ts
+utils/is_zod_schema.d.cts
 vectorstores.cjs
 vectorstores.js
 vectorstores.d.ts

langchain-core/langchain.config.js

@@ -61,6 +61,7 @@ export const config = {
     "utils/tiktoken": "utils/tiktoken",
     "utils/types": "utils/types",
     "utils/beta_warning": "utils/beta_warning",
+    "utils/is_zod_schema": "utils/is_zod_schema",
     vectorstores: "vectorstores",
   },
   tsConfigPath: resolve("./tsconfig.json"),

langchain-core/package.json

@@ -534,6 +534,15 @@
       "import": "./utils/beta_warning.js",
       "require": "./utils/beta_warning.cjs"
     },
+    "./utils/is_zod_schema": {
+      "types": {
+        "import": "./utils/is_zod_schema.d.ts",
+        "require": "./utils/is_zod_schema.d.cts",
+        "default": "./utils/is_zod_schema.d.ts"
+      },
+      "import": "./utils/is_zod_schema.js",
+      "require": "./utils/is_zod_schema.cjs"
+    },
     "./vectorstores": {
       "types": {
         "import": "./vectorstores.d.ts",
@@ -743,6 +752,10 @@
     "utils/beta_warning.js",
     "utils/beta_warning.d.ts",
     "utils/beta_warning.d.cts",
+    "utils/is_zod_schema.cjs",
+    "utils/is_zod_schema.js",
+    "utils/is_zod_schema.d.ts",
+    "utils/is_zod_schema.d.cts",
     "vectorstores.cjs",
     "vectorstores.js",
     "vectorstores.d.ts",

langchain-core/src/utils/is_zod_schema.ts

@@ -0,0 +1,18 @@
+import { type z } from "zod";
+
+/**
+ * Given either a Zod schema, or plain object, determine if the input is a Zod schema.
+ * 
+ * @param {z.ZodType<RunOutput> | Record<string, any>} input 
+ * @returns {boolean} Whether or not the provided input is a Zod schema. 
+ */
+export function isZodSchema<
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  RunOutput extends Record<string, any> = Record<string, any>
+>(
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  input: z.ZodType<RunOutput> | Record<string, any>
+): input is z.ZodType<RunOutput> {
+  // Check for a characteristic method of Zod schemas
+  return typeof (input as z.ZodType<RunOutput>)?.parse === "function";
+}