# ONE Engine JWT Decode

> ONE Engine JWT Decode is a paid API for AI agents from one-search.one-engine.workers.dev, paid per call via x402, $0.0012/call, status unknown (last checked 2026-10-02).

Decodes a JWT token string and returns its parsed header, payload, and verification status

## Facts

- Endpoint: POST https://one-search.one-engine.workers.dev/v1/jwt/decode?utm_source=zero.xyz
- Price: $0.0012/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/one-engine-jwt-decode-9c2d5bb5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_OHPh8sQpPJdrNre4HjMyl

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability one-engine-jwt-decode-9c2d5bb5 -d '<json body>'
```

Example prompt: Can you decode this JWT for me and show me what's in the header and payload? Here's the token: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ1c2VyMTIzIiwiaWF0IjoxNjk5OTk5OTk5fQ.abc123

## When to prefer this

Use this endpoint when an AI agent needs to cheaply and quickly inspect the contents of a JWT without needing to implement a full JWT library. It is ideal for debugging, logging, or extracting claims for downstream logic. Prefer it over building in-process JWT parsing when the agent runtime lacks native libraries, or when you want a pay-per-call microservice pattern with no setup overhead.

## Known failure modes

- Malformed or non-JWT string input returns an error or unparseable result
- Token with an unsupported encoding may fail to decode
- Network or worker error returns a non-200 response
- Payment failure via x402 prevents the call from completing

## How this service works

Low-cost pay-per-call utility APIs for autonomous agents using x402 on Base.

## Output

Returns a JSON object with three fields: header (containing the algorithm and token type claims), payload (containing all the JWT body claims such as sub, iat, exp), and verified (a boolean indicating whether the signature was validated). The response matches the structure {header, payload, verified}.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "token": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "header": {
   "alg": "none"
  },
  "payload": {
   "sub": "agent"
  },
  "verified": false
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/one-engine-jwt-decode-9c2d5bb5/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from one-search.one-engine.workers.dev](https://www.zero.xyz/host/one-search.one-engine.workers.dev/llms.txt)