# JWT Decoder

> JWT Decoder is a paid API for AI agents from conclavex402p04.pythonanywhere.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-18).

Decodes a JWT token, parsing its header and payload claims without verifying the signature.

## Facts

- Endpoint: POST https://conclavex402p04.pythonanywhere.com/u/jwt?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/jwt-decoder-6424c853
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_6liiOhGAk_pbotk4FQq44

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 jwt-decoder-6424c853 -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.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c

## When to prefer this

Use this endpoint when you need to quickly inspect the contents of a JWT — its header fields (algorithm, key ID) and payload claims (subject, expiry, custom data) — without needing to verify its authenticity. Ideal for debugging, logging, or pre-flight inspection in agent pipelines where signature verification is handled elsewhere.

## Known failure modes

- Malformed or non-base64 JWT input returns an error
- Missing or empty token body causes validation failure
- Token with too many or too few segments (not 3-part) may fail to parse
- Payment failure (402) if x402 payment is not included or insufficient

## How this service works

Decode a JWT — parse header and payload claims without a key (no signature verification).

## Output

Returns a JSON object with two top-level keys: 'header' (containing JWT header fields like alg and typ) and 'payload' (containing all claims encoded in the JWT body such as sub, iat, exp, and any custom claims). No signature verification is performed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object"
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST",
      "PUT",
      "PATCH"
     ],
     "type": "string"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "queryParams": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "header": {
   "alg": "none"
  },
  "payload": {
   "sub": "1"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/jwt-decoder-6424c853/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from conclavex402p04.pythonanywhere.com](https://www.zero.xyz/host/conclavex402p04.pythonanywhere.com/llms.txt)