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LLM Output Guard | JSON Schema Validation for Agent Output

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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.

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Pay per usage

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Developer

Brandon Mensing

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a month 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

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

JSON Schema Validator for LLM and Agent Output API in Python

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

Install the apify-client

$pip install apify-client

Other API clients include:

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

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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