# KHOTEM Notary & Session Verification

> KHOTEM Notary & Session Verification is a paid API for AI agents from khotem.com, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-13).

Provides paid cryptographic notarization and session verification with audit trail via USDC micropayment on Base, no signup required.

## Facts

- Endpoint: POST https://khotem.com/api/verify
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/khotem-notary-session-verification-ac2444d9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_uOsTRtl53RJbV8lz77zCn

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 khotem-notary-session-verification-ac2444d9 -d '<json body>'
```

Example prompt: Notarize this document hash 0xabc123... using KHOTEM — I want a cryptographic seal and audit record proving it existed right now, and pay the $0.05 USDC fee on Base.

## When to prefer this

Choose this endpoint when you need a lightweight, permissionless cryptographic notarization or session verification without account creation or KYC. It is ideal for AI agents that need to seal documents, prove data integrity, or create audit trails on-demand with a $0.05 USDC micropayment on Base. Prefer it over traditional notary APIs when anonymity, no-signup access, and blockchain-backed proofs are required.

## Known failure modes

- Insufficient USDC payment — payment below $0.05 or on wrong chain returns payment required error
- Invalid or malformed payload — missing required content hash or session data returns 400 bad request
- Payment not confirmed on Base — pending transaction may cause verification to fail or time out
- Duplicate submission — resubmitting same content within a short window may be rejected or treated as new record
- Network congestion on Base — blockchain confirmation delays may cause slow response or timeout

## How this service works

Paid cryptographic witness services for autonomous agents and humans: seals, attestations, verification, audit, sealed document thread. x402-native micropayments, USDC on Base / Polygon / Solana, direct on-chain verification. No accounts, no API keys, no KYC.

## Output

Returns a cryptographic seal or notarization certificate with a timestamp, verification status, and audit record proving the submitted content or session existed and was valid at the time of the call. Typically includes a proof hash, seal identifier, and audit log reference.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "seal"
 ],
 "properties": {
  "seal": {
   "type": "object"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "ok": 1,
 "total": 1,
 "results": [
  {
   "ok": true,
   "root": "9f2c…"
  }
 ],
 "verdict": "✓ ALL VERIFIED",
 "payment_seal": "a1b2c3d4e5f60708",
 "verdict_seal": "1020304050607080"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/khotem-notary-session-verification-ac2444d9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from khotem.com](https://www.zero.xyz/host/khotem.com/llms.txt)