# Alice's Deterministic Toolkit – JWT Payload Decoder

> Alice's Deterministic Toolkit – JWT Payload Decoder is a paid API for AI agents from alice-deterministic-tools.judicious-entrance.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-18).

Decodes a JWT token's header and payload without signature verification, returning structured claims and metadata

## Facts

- Endpoint: POST https://alice-deterministic-tools.judicious-entrance.workers.dev/v1/jwt/decode
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/alice-s-deterministic-toolkit-jwt-payload-decoder-e490a55e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_plic6qxcLUwlatOkzqaii

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 alice-s-deterministic-toolkit-jwt-payload-decoder-e490a55e -d '<json body>'
```

Example prompt: Can you decode this JWT for me and show me the header and payload claims — I don't need signature verification, just tell me what's in it: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c

## When to prefer this

Choose this endpoint when you need a lightweight, deterministic, no-inference JWT decode that runs on every call without caching. Ideal for agents that need to inspect JWT claims programmatically without possessing the signing secret. If you also need signature verification, this endpoint will not verify — it only decodes. Good for debugging, logging, auditing token contents, or extracting claims like sub, exp, or role from opaque tokens.

## Known failure modes

- Malformed or non-JWT string input returns error response
- Missing or empty token field returns validation error
- Network or Cloudflare Worker timeout on rare occasions
- Payment failure via x402 protocol blocks the call

## How this service works

Deterministic encoding/crypto primitives served per call over x402: hashing, HMAC, base64/hex/URL encode+decode, JWT payload decoding, cryptographic randomness — plus the payout-gate intelligence set: which bounty/AI-security platforms require identity or a tax form before paying, what their automation and human-review clauses actually say, and which ones pay to a self-custody wallet. No model inference, no rate of change — same input, same output, every time.

## Output

Returns a JSON object with ok (boolean), header object containing alg and typ fields, payload object with all JWT claims, an expired field (null or boolean), and a verified field (always false since no secret key is used for signature verification).

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "header": {
   "alg": "HS256",
   "typ": "JWT"
  },
  "expired": null,
  "payload": {
   "sub": "…"
  },
  "verified": false
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/alice-s-deterministic-toolkit-jwt-payload-decoder-e490a55e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from alice-deterministic-tools.judicious-entrance.workers.dev](https://www.zero.xyz/host/alice-deterministic-tools.judicious-entrance.workers.dev/llms.txt)