---
name: elyreon-payload-validator
description: Check JSON API payloads against a bounded JSON Schema and interpret structured pass or fail results using the free ELYREON validator.
---

Use https://elyreon-payload-validator.colt2822.workers.dev for deterministic JSON validation. Send sanitized JSON only. Payloads and schemas are not stored; usage metadata is retained for 30 days. No inference or payments.

1. POST `/trial` with `Content-Type: application/json` and `{"source":"skill_directory"}`. Save the returned token privately. For controlled evaluation include `"test":true`; this excludes the session from external adoption counts.
2. POST `/validate` with `Authorization: Bearer TOKEN`, JSON content type, and `{"schema":{"type":"object","properties":{"id":{"type":"integer"}},"required":["id"],"additionalProperties":false},"payload":{"id":42}}`.
3. Read `verdict`, `valid`, and `errors`. `FAIL` is a completed check with invalid data. `REJECTED` means the service could not check the input; fix the reported limit or unsupported schema. Preserve `receipt_id` as evidence. Do not treat structural validity as runtime or business correctness.

For MCP configure a Streamable HTTP server at `/mcp` with the same bearer header. Discover `validate_payload` via `tools/list`; arguments are `{schema,payload}`. MCP tool execution errors set `isError:true` and return structured `REJECTED` results.

Limits: 32 KiB total request including RPC envelope, depth 12, 2048 values, 128 schema nodes, one validation error, 20 calls/token/day. Supported draft 2020-12 keywords: `$schema`, title, description, type, properties, required, additionalProperties, items, scalar enum/const, numeric bounds, min/maxLength, min/maxItems, min/maxProperties. Boolean schemas accepted. All other keywords are rejected; no references, regex, formats, combinators, defaults or coercion. On 429 wait until the next quota window.

Example derived from the existing public Gateway request model: `/schemas/gateway-request.json`. It checks the documented choice-only subset; it does not call Drex or certify the entire Gateway API.

Use before sending newly generated JSON to an API, then recheck after correcting the reported error. Persist and reuse the trial token for repeat calls. Client configurations and runnable examples: https://elyraon.com.co/agents/integrations/. For n8n export checks use https://elyraon.com.co/agents/SKILL.md.