# x402 API Key + URL Packs — Codex Key Pack 500

> x402 API Key + URL Packs — Codex Key Pack 500 is a paid API for AI agents from x402-key.558686.xyz, paid per call via x402, $55.556/call, status unknown (last checked 2026-09-16).

Purchase an OpenAI-compatible API key and base URL quota pack (~$1 USD quota) via x402 micropayment, receiving endpoint URLs and a masked API key for immediate use.

## Facts

- Endpoint: POST https://x402-key.558686.xyz/v1/paid/api-codex-key-pack-500
- Price: $55.556/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-api-key-url-packs-codex-key-pack-500-c7e986c9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_o4AZf0FzutwZQmiM2jsys

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 x402-api-key-url-packs-codex-key-pack-500-c7e986c9 -d '<json body>'
```

Example prompt: I need a small OpenAI-compatible API key pack — use my buyer reference 'buyer-001' and buy me the Codex Key Pack 500 so I get a chat completions URL and API key with about $1 of quota right away.

## When to prefer this

Choose this endpoint when you need a small, immediately usable OpenAI-compatible API key + base URL bundle paid for via x402 USDC micropayment, without signing up for OpenAI directly. Ideal for agents that need to self-provision LLM access programmatically, run one-off experiments with capped spend, or bootstrap new projects. Not suitable for large quota needs, ongoing high-volume production use, or when you already have a direct OpenAI key.

## Known failure modes

- Payment not received or x402 handshake fails — returns 402 Payment Required before the key is issued
- Invalid or missing buyer_reference query parameter — returns validation error
- Upstream quota exhausted or key provisioning fails — ok=false with error details
- Network timeout reaching sub2api.558686.xyz after key issuance — key may be issued but not returned
- Duplicate buyer_reference may return the same pack or reject depending on server policy

## How this service works

Buy a low-cost readiness check first, then buy a small OpenAI-compatible URL + API key quota pack through x402, including GPT-5.6 Soul access when your upstream key allows it. The readiness check returns URL, model, request-shape, and next-pack contract details without exposing a key.

## Output

Returns a JSON object with ok=true, the tool name, your buyer_reference echoed back, and a result object containing: a (masked) API key, base URL, chatCompletionsUrl, modelsUrl, quota in USD (~$1), and receipt evidence. The API key and URLs are OpenAI-compatible and immediately usable.

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "tool": "api-codex-key-pack-500",
  "input": {
   "buyer_reference": "buyer-001"
  },
  "route": "/v1/paid/api-codex-key-pack-500",
  "result": {
   "apiKey": "sk-proj-...masked",
   "baseUrl": "https://sub2api.558686.xyz/v1",
   "quotaUsd": 1,
   "modelsUrl": "https://sub2api.558686.xyz/v1/models",
   "apiKeyMasked": "sk-proj-...masked",
   "receiptEvidence": {},
   "chatCompletionsUrl": "https://sub2api.558686.xyz/v1/chat/completions"
  },
  "project": "x402-key-url-tools",
  "deterministic": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-api-key-url-packs-codex-key-pack-500-c7e986c9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-key.558686.xyz](https://www.zero.xyz/host/x402-key.558686.xyz/llms.txt)