# JWT Decoder

> JWT Decoder is a paid API for AI agents from conclavex402.pythonanywhere.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-18).

Decodes a JWT token by parsing its header and payload claims without performing signature verification.

## Facts

- Endpoint: POST https://conclavex402.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-43b5904f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_KnOhIUoKf5XP3YZoCpHt9

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-43b5904f -d '<json body>'
```

Example prompt: Can you decode this JWT for me and show me what's in the header and payload: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c

## When to prefer this

Use this endpoint when you need to quickly inspect or extract the header and payload claims from a JWT token without needing to verify its signature — ideal for debugging, logging, or reading claims in a trusted internal context. Not appropriate when signature verification is required for security enforcement.

## Known failure modes

- Malformed or non-JWT string input returns an error
- Missing required 'input' body field causes validation failure
- Token with invalid base64url encoding in header or payload fails to decode
- Passing an empty string or non-string JWT value returns an error

## 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 fields: 'header' containing the decoded JWT header claims (e.g. alg, typ) and 'payload' containing the decoded JWT payload claims (e.g. sub, iat, exp, 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-43b5904f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from conclavex402.pythonanywhere.com](https://www.zero.xyz/host/conclavex402.pythonanywhere.com/llms.txt)