Validate Parse Script | Captain Docs

Validates a JavaScript parsing script without running it against real data. Upload your .js file as multipart/form-data under the file field. Checks that the script parses cleanly and exports a default function. Use this before uploading a script to catch syntax errors and structural problems. The return-type contract (must return a string) is enforced at indexing time by json_handler against your real JSON.

Authentication

AuthorizationBearer

Bearer token authentication using API key

Request

This endpoint expects a multipart form containing a file.

filefileRequired

The .js parsing script file to validate. Max 1 MB.

Response

Validation result. Returned for both valid AND invalid scripts.

validboolean

True if the script passes all validation checks.

errorstring or null

Human-readable error message. Null when valid=true.

error_typeenum or null

Error category. Null when valid=true.

Allowed values:

1	import requests
2
3	BASE_URL = "https://api.runcaptain.com"
4	API_KEY = "your_api_key"
5
6	headers = {
7	"Authorization": f"Bearer {API_KEY}",
8	}
9
10	# Upload a .js file from disk
11	with open("my-parser.js", "rb") as f:
12	response = requests.post(
13	f"{BASE_URL}/v2/parsing-scripts/validate",
14	headers=headers,
15	files={"file": ("my-parser.js", f, "application/javascript")},
16	timeout=30.0
17	)
18
19	result = response.json()
20	if result["valid"]:
21	print("Script is valid!")
22	else:
23	print(f"Error ({result['error_type']}): {result['error']}")

1	{
2	"valid": true
3	}

Authentication

Headers

Request

Response