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modell.halowerk.com Output Validator
x402
modell.halowerk.com Output Validator is a paid API for AI agents from modell.halowerk.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-12).
Validates LLM output against a JSON Schema (Draft 2020-12 or draft-07), reporting each violation with its JSON path, the broken rule, and a fix suggestion, while also unwrapping code-fenced or prose-wrapped model responses before validation.
Price / call$0.002
Success—
StatusUnknown
How this service works
Validates output against a JSON Schema and reports each violation with its JSON path, the rule it broke and a sentence saying what to change. Accepts either a parsed object or the raw string a model returned: a payload wrapped in a code fence or surrounded by prose is unwrapped, and the wrapping is reported separately from schema errors so you fix the right layer. Draft 2020-12 and draft-07 are both supported, along with the common string formats.
Output
A structured report listing each schema violation with its JSON path, the specific schema rule that was broken, and a plain-language sentence describing what to change. If the model output was wrapped in a code fence or prose, the unwrapping is reported separately from the schema errors so the caller can address formatting and schema problems independently.
Example use cases
Catching schema errors in agent tool calls
“My agent just returned this JSON blob but it might be wrapped in markdown. Validate it against this schema and list every field that fails, what rule each one breaks, and how to fix it.”
Debugging draft 2020-12 compliance for a pipeline
“I'm getting malformed responses from my LLM pipeline — can you validate this raw string against my draft 2020-12 schema and tell me the JSON path and violation reason for every error?”
Separating wrapping issues from schema errors
“The model returned its answer inside a code fence surrounded by some prose — unwrap it, then validate against my draft-07 schema, and report the wrapping separately from any actual schema violations.”
Technical details
Endpoint
POSThttps://modell.halowerk.com/v1/output-validate?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need to validate raw or code-fenced LLM output against a JSON Schema and want per-violation detail (JSON path + rule + fix hint) rather than a simple pass/fail. Especially useful when model responses may be wrapped in markdown or prose that needs stripping before validation. Supports both Draft 2020-12 and draft-07, making it suitable for modern and legacy schema use cases. Prefer this over generic JSON validators when working in an agentic pipeline where the model output format is unpredictable.
Side effects
- Invalid or malformed JSON Schema provided — returns schema parse error
- Model output cannot be unwrapped to valid JSON — returns parse failure before schema validation
- Unsupported JSON Schema draft version — only Draft 2020-12 and draft-07 are supported
- Empty or missing payload — returns validation error on the request itself
- Network timeout for very large payloads
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| output | — | The model answer, as a parsed JSON value. Either this or output_text. |
| schema | object | JSON Schema to validate against. |
| all_errors | boolean | Report every violation instead of stopping at the first. |
| output_text | string | The raw answer as text. Code fences and surrounding prose are stripped. |
| suggest_repairs | boolean | List repairable problems (defaultable missing fields, extra fields). |
Tags
x402
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