# OnTopX402 Link Ranking Bid

> OnTopX402 Link Ranking Bid is a paid API for AI agents from ontopx402.com, paid per call via x402, $1/call, status unknown (last checked 2026-10-18).

Submit a paid bid to rank a URL on the OnTopX402 leaderboard — higher bids earn higher placement, and repeated bids on the same URL accumulate.

## Facts

- Endpoint: POST https://ontopx402.com/api/bid?utm_source=zero.xyz
- Price: $1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ontopx402-link-ranking-bid-3e399e59
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_uRiDiIA916PdGjDRc2sUr

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 ontopx402-link-ranking-bid-3e399e59 -d '<json body>'
```

Example prompt: Bid $5 on ontopx402 to rank my site https://example.com — describe it as 'The best example domain on the web' so it shows up prominently on the board.

## When to prefer this

Use this endpoint when the goal is to gain public leaderboard visibility on ontopx402.com by paying a variable bid amount. The rank is directly determined by bid size, making it ideal for competitive link promotion where the user controls their spend. Prefer this over free SEO or traditional ad networks when the user wants instant, transparent, pay-to-rank placement with no auction complexity.

## Known failure modes

- Bid amount below $1 minimum — rejected with validation error
- URL missing or malformed — schema validation failure
- Description exceeds 255 characters — truncation or rejection
- Payment failure via x402 protocol — bid not recorded
- Duplicate URL bid accepted but accumulates rather than replacing previous bid

## How this service works

Rank on ontopx402.com for example.com

## Output

A confirmation that the bid was recorded, updating the leaderboard position of the submitted URL. The URL's total accumulated bid amount determines its rank among all entries on the board.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "description": "The link you want ranked. One entry per link; bidding again on the same link adds to its total."
  },
  "amount": {
   "type": "string",
   "description": "How much to bid, in US dollars, minimum $1. This is the amount you pay AND the amount that decides your rank — the 402 is priced at exactly this figure."
  },
  "description": {
   "type": "string",
   "description": "What the link is, in at most 255 characters. Shown on the board next to your entry."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "url": "https://example.com",
  "name": "example.com",
  "page": "https://ontopx402.com/e/example-com",
  "rank": 1,
  "network": "eip155:8453",
  "paid_usd": "1.00",
  "amount_usd": "1.00",
  "description": "What this link is.",
  "transaction": "0x…"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/ontopx402-link-ranking-bid-3e399e59/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ontopx402.com](https://www.zero.xyz/host/ontopx402.com/llms.txt)