@langgraph-js/sdk/src/tool/utils.ts

The UI SDK for LangGraph - seamlessly integrate your AI agents with frontend interfaces

/**
 * copy and modify from copilotkit
 * https://github.com/copilotkit/copilotkit
 *
 * MIT License
 */
import { z, ZodRawShape } from "zod";
import { Parameter } from "./copilotkit-actions.js";

export type JSONSchemaString = {
    type: "string";
    description?: string;
    enum?: string[];
};

export type JSONSchemaNumber = {
    type: "number";
    description?: string;
};

export type JSONSchemaBoolean = {
    type: "boolean";
    description?: string;
};

export type JSONSchemaObject = {
    type: "object";
    properties?: Record<string, JSONSchema>;
    required?: string[];
    description?: string;
};

export type JSONSchemaArray = {
    type: "array";
    items: JSONSchema;
    description?: string;
};

export type JSONSchema = JSONSchemaString | JSONSchemaNumber | JSONSchemaBoolean | JSONSchemaObject | JSONSchemaArray;

export function actionParametersToJsonSchema(actionParameters: Parameter[]): JSONSchema {
    // Create the parameters object based on the argumentAnnotations
    let parameters: { [key: string]: any } = {};
    for (let parameter of actionParameters || []) {
        parameters[parameter.name] = convertAttribute(parameter);
    }

    let requiredParameterNames: string[] = [];
    for (let arg of actionParameters || []) {
        if (arg.required !== false) {
            requiredParameterNames.push(arg.name);
        }
    }

    // Create the ChatCompletionFunctions object
    return {
        type: "object",
        properties: parameters,
        required: requiredParameterNames,
    };
}

function convertAttribute(attribute: Parameter): JSONSchema {
    switch (attribute.type) {
        case "string":
            return {
                type: "string",
                description: attribute.description,
                ...(attribute.enum && { enum: attribute.enum }),
            };
        case "number":
        case "boolean":
            return {
                type: attribute.type,
                description: attribute.description,
            };
        case "object":
        case "object[]":
            const properties = attribute.attributes?.reduce(
                (acc, attr) => {
                    acc[attr.name] = convertAttribute(attr);
                    return acc;
                },
                {} as Record<string, any>
            );
            const required = attribute.attributes?.filter((attr) => attr.required !== false).map((attr) => attr.name);
            if (attribute.type === "object[]") {
                return {
                    type: "array",
                    items: {
                        type: "object",
                        ...(properties && { properties }),
                        ...(required && required.length > 0 && { required }),
                    },
                    description: attribute.description,
                };
            }
            return {
                type: "object",
                description: attribute.description,
                ...(properties && { properties }),
                ...(required && required.length > 0 && { required }),
            };
        default:
            // Handle arrays of primitive types and undefined attribute.type
            if (attribute.type?.endsWith("[]")) {
                const itemType = attribute.type.slice(0, -2);
                return {
                    type: "array",
                    items: { type: itemType as any },
                    description: attribute.description,
                };
            }
            // Fallback for undefined type or any other unexpected type
            return {
                type: "string",
                description: attribute.description,
            };
    }
}

export function convertJsonSchemaToZodRawShape(jsonSchema: any): ZodRawShape {
    const spec: { [key: string]: z.ZodSchema } = {};
    for (const [key, value] of Object.entries(jsonSchema.properties)) {
        spec[key] = convertJsonSchemaToZodSchema(value, jsonSchema.required ? jsonSchema.required.includes(key) : false);
    }
    return spec;
}

export function convertJsonSchemaToZodSchema(jsonSchema: any, required: boolean): z.ZodSchema {
    if (jsonSchema.type === "object") {
        const spec: { [key: string]: z.ZodSchema } = {};

        if (!jsonSchema.properties || !Object.keys(jsonSchema.properties).length) {
            return !required ? z.object(spec).optional() : z.object(spec);
        }

        for (const [key, value] of Object.entries(jsonSchema.properties)) {
            spec[key] = convertJsonSchemaToZodSchema(value, jsonSchema.required ? jsonSchema.required.includes(key) : false);
        }
        let schema = z.object(spec).describe(jsonSchema.description);
        return required ? schema : schema.optional();
    } else if (jsonSchema.type === "string") {
        let schema = z.string().describe(jsonSchema.description);
        return required ? schema : schema.optional();
    } else if (jsonSchema.type === "number") {
        let schema = z.number().describe(jsonSchema.description);
        return required ? schema : schema.optional();
    } else if (jsonSchema.type === "boolean") {
        let schema = z.boolean().describe(jsonSchema.description);
        return required ? schema : schema.optional();
    } else if (jsonSchema.type === "array") {
        let itemSchema = convertJsonSchemaToZodSchema(jsonSchema.items, true);
        let schema = z.array(itemSchema).describe(jsonSchema.description);
        return required ? schema : schema.optional();
    }
    throw new Error("Invalid JSON schema");
}