Pricing

from $1.00 / 1,000 record validateds

LLM Output Guard | JSON Schema Validation for Agent Output

Check that your model's JSON matches the schema you asked for. Every failure comes back with its path, the keyword it broke, and the repair that would fix it. Shape repairs are opt-in and never invent content, so a repair can never hide a real failure.

Pricing

from $1.00 / 1,000 record validateds

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Developer

Brandon Mensing

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Monthly active users

4 days ago

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You can access the LLM Output Guard | JSON Schema Validation for Agent Output programmatically from your own applications by using the Apify API. You can also choose the language preference from below. To use the Apify API, you’ll need an Apify account and your API token, found in API & Integrations in Apify Console.

Python

JavaScript

CLI

OpenAPI

HTTP

MCP

1import { ApifyClient } from 'apify-client';
2
3// Initialize the ApifyClient with your Apify API token
4// Replace the '<YOUR_API_TOKEN>' with your token
5const client = new ApifyClient({
6    token: '<YOUR_API_TOKEN>',
7});
8
9// Prepare Actor input
10const input = {
11    "schema": {
12        "type": "object",
13        "required": [
14            "sku",
15            "name",
16            "price",
17            "inStock"
18        ],
19        "additionalProperties": false,
20        "properties": {
21            "sku": {
22                "type": "string",
23                "pattern": "^[A-Z]{3}-\\d{4}$"
24            },
25            "name": {
26                "type": "string",
27                "minLength": 1
28            },
29            "price": {
30                "type": "number",
31                "minimum": 0
32            },
33            "inStock": {
34                "type": "boolean"
35            },
36            "status": {
37                "type": "string",
38                "enum": [
39                    "active",
40                    "discontinued"
41                ]
42            }
43        }
44    },
45    "items": [
46        {
47            "sku": "ABC-1234",
48            "name": "Widget",
49            "price": 9.99,
50            "inStock": true,
51            "status": "active"
52        },
53        {
54            "sku": "ABC-5678",
55            "name": "Gizmo",
56            "price": "$19.99",
57            "inStock": "yes",
58            "status": "Active"
59        },
60        {
61            "sku": "nope",
62            "name": "",
63            "price": -3,
64            "hallucinatedField": "invented by the model"
65        }
66    ]
67};
68
69// Run the Actor and wait for it to finish
70const run = await client.actor("broomwagon/llm-output-guard").call(input);
71
72// Fetch and print Actor results from the run's dataset (if any)
73console.log('Results from dataset');
74console.log(`💾 Check your data here: https://console.apify.com/storage/datasets/${run.defaultDatasetId}`);
75const { items } = await client.dataset(run.defaultDatasetId).listItems();
76items.forEach((item) => {
77    console.dir(item);
78});
79
80// 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/js/docs

JSON Schema Validator for LLM and Agent Output API in JavaScript

The Apify API client for JavaScript is the official library that allows you to use LLM Output Guard | JSON Schema Validation for Agent Output API in JavaScript or TypeScript, providing convenience functions and automatic retries on errors.

Install the apify-client

$npm install apify-client

Other API clients include:

LLM Output Guard | JSON Schema Validation for Agent Output API in Python

LLM Output Guard | JSON Schema Validation for Agent Output API through CLI

LLM Output Guard | JSON Schema Validation for Agent Output OpenAPI definition

LLM Output Guard | JSON Schema Validation for Agent Output API

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