How it works

Pzero is three layers joined by a router. Supply and demand never meet directly. The router clears them at inference time.

Seller marketplace (supply)        Buyer marketplace (demand)
  Venice DIEM @ 30–80¢ / $1 face     prepaid USDC; max price = ceiling
            \                              /
             ▼                            ▼
                   Router (inference edge)
        cheapest eligible offer ≤ buyer max → forward → settle (10% fee)

The key idea: the router joins supply and demand at request time. Buyers do not browse listings or pick a seller, they set a ceiling, and the router clears the cheapest eligible posted supply for them.

The three layers

• Seller marketplace: suppliers register inference keys and post offers priced in the 30–80¢ corridor, backed by their daily DIEM capacity. See Sellers.
• Buyer marketplace: buyers prepay USDC and set a max price (their minimum required discount). See Buyers.
• Router: on each request, selects the cheapest eligible offer at or below the buyer's max, forwards once, meters usage, and settles. See The router.

A request, end to end

1. A buyer calls POST /v1/chat/completions with a Bearer API key.
2. The router resolves the key to a wallet and its max price.
3. A per-wallet lock admits one in-flight completion (others get 429).
4. The confirmed USDC balance is pre-checked against the estimated cost.
5. The router selects the cheapest eligible offer whose posted price is at or below the buyer's max and has enough routable capacity.
6. It forwards the request to that supplier's upstream key, metering the real capacity burn.
7. On success it settles in a single database transaction: buyer debited gross, supplier credited net (90%), platform credited the fee (10%).
8. Audit rows are written and the OpenAI-compatible response is returned.

If upstream succeeds but settlement fails, the request fails closed. No successful body is returned. See Ledgers & settlement.

Substrate

• Chain: Base mainnet (chain ID 8453).
• Settlement currency: USDC (6 decimals). API amounts are micro-USDC (1 USDC = 1,000,000).
• Funding: x402 (HTTP 402 + EIP-3009 exact). See x402 top-up.
• Web identity: SIWE (EIP-4361). Inference auth: Bearer pzero_… keys. See Authentication.
• Token: PZERO (ERC-20 on Base). See PZERO token & treasury.