MPP (Pay Per Call)

Pay per API call with no signup and no API key. Agents use MPP over Tempo (USDC.e on mainnet) at https://mpp.trychannel3.com.

	MPP	API key
Signup	None	Free account
Billing	$0.007 USDC.e per call (on-chain)	1000 free credits/mo, then same rate via Stripe
Best for	Agents, scripts, one-off automation	Dashboard, commissions, higher volume

Send x-api-key or satisfy the MPP payment challenge — same endpoints either way.

Supported endpoints

MPP works on these POST routes only:

Everything else (/v1/browse, product detail, brands, etc.) requires an API key.

1. Set up a Tempo wallet with USDC.e:

curl -fsSL https://tempo.xyz/install | bash
tempo wallet login
tempo wallet fund

2. Make a paid request — the CLI handles 402 → pay → retry:

tempo request -X POST \
  --json '{"query":"running shoes"}' \
  https://mpp.trychannel3.com/v1/search

Also works with mppx (npx mppx@latest ... --network mainnet). Plain curl returns 402 but cannot complete payment.

Each payment credential is single-use. Pagination (page_token) is a new paid call. Failed responses after payment are refunded automatically.

Code	Meaning
402	Payment required (or credential already used)
403	Payer address blocked
422	Invalid request body
503	Payment infra unavailable — retry

See MPP and the Tempo wallet CLI for protocol details.