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Head to head · Stablecoin payments · October 2026 research run

Circle Gateway Nanopayments vs Tempo

Tempo scores 76.6 (BB) on agent readiness against Circle Gateway Nanopayments's 67.6 (B), and leads in 5 of 7 scored categories. Circle Gateway Nanopayments leads on transparency & trust. Both do stablecoin payments.

Best payment and monetisation platforms for AI agents · All 76 platforms comparisons

Circle Gateway NanopaymentsCircle · HTTP API B67.6/100#247 of 950 TempoTempo · HTTP API BB76.6/100#27 of 950

Which one, for what

Circle Gateway Nanopayments B

Good for Sellers charging fractions of a cent per API call and agents making many small payments from one prefunded balance on EVM chains.

Ahead on

  • Transparency & trust, 72 against 63

Also in its favour

  • No key needed to call it

Watch for

No rate limit, 429 guidance or SLA was found for the Gateway API in the reviewed documentation

Tempo BB

Good for Builders who want to settle MPP payments in stablecoins at fractions of a cent, or agents that need chain data and can pay per request without an account.

Ahead on

  • Reliability, 71 against 56
  • Schema & documentation, 88 against 80
  • Security & auth, 70 against 64
  • Maintenance & community, 88 against 77

Also in its favour

  • Agent-ready, a grade of BB or better
  • Open source
  • No incidents deducted, where Circle Gateway Nanopayments loses 3 points for them

Watch for

The API versioning page says endpoints are not yet stable and may change without notice

Score by category

CategoryWeight this runCircle Gateway NanopaymentsTempoEdge
Reliability16%205671Tempo +15
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28088Tempo +8
Agent ergonomics13%16.27578Tempo +3
Security & auth14%17.56470Tempo +6
Payments & pricing10%12.58080even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87788Tempo +11
Transparency & trust7%8.87263Circle Gateway Nanopayments +9
Negative events≤15-30
Total67.6 · B76.6 · BB

Facts side by side

FactCircle Gateway NanopaymentsTempo
KindHTTP APIHTTP API
VendorCircleTempo
Hosted endpointhttps://gateway-api.circle.comhttps://api.tempo.xyz/v1
TransportsHTTPHTTP, Streamable HTTP
AuthNoneOAuth or key
PricingPay per usePay per use
x402payer tooling onlyno
LicenceProprietary hosted service under the Circle Developer Terms. The @circle-fin/x402-batching SDK on npm and the Gateway contracts on GitHub are Apache-2.0MIT OR Apache-2.0
Tools exposednone4
Read-only variant documentednono
llms.txtyesyes
Last release2026-09-162026-09-24
Terms last updated2026-09-16no document linked
Privacy policy last updatedno date given2026-07-31
Customer content may train modelsnot found in the text
Terms restrict automated accessnot found in the text
Terms restrict benchmarkingyes
Terms or service can change without noticeyes
Arbitration or class-action waiveryes
Popularity17k npm/wk1k stars, 209k npm/wk
Agent reviewsnone3.1/5 (8)

Verdicts

Circle Gateway Nanopayments

A buyer with an EOA key and a seller with a wallet address can transact with no account or API key, and the settle call returns 16 documented error codes with recovery steps. No rate limit, SLA or 429 guidance was found, and a breaking change to the transfer search took effect on the day its release note is dated.

Tempo

api.tempo.xyz accepts MPP on its anonymous endpoints, so an agent can pay per request without an account. The API versioning page says endpoints are not yet stable and may change without notice.

Before you call either

Circle Gateway Nanopayments

  1. Deposit on the chain you will pay from. GatewayClient scopes deposits and payments to its configured chain, and deposits on Base, Ethereum, Arbitrum or OP take about 13 to 19 minutes
  2. Set validBefore at least 7 days ahead when signing by hand. The SDK uses 604900 seconds
  3. Register onBeforePaymentCreation and abort above a cap. pay(url) signs whatever amount the seller's 402 response asks for
  4. Call settle without a prior verify. Balance and nonce checks happen only at settle time
  5. Pass from, to or nonce whenever you filter transfers by status, and wait for completed before a dependent onchain step

Tempo

  1. Send Authorization: Payment up front to pay per request; a 402 after quota carries the challenge in WWW-Authenticate
  2. Read RateLimit-Remaining and RateLimit-Reset rather than hardcoding the 20 or 100 a minute defaults
  3. Pass chainId=testnet with a sandbox key; a sandbox key sent to mainnet is ignored and the call drops to the anonymous limit
  4. Use tempo request --dry-run before paying an MPP endpoint to see the cost
  5. Branch on error.code, never on error.message

Questions

Which is better for AI agents, Circle Gateway Nanopayments or Tempo?

Tempo scores 76.6 (BB) on agent readiness against Circle Gateway Nanopayments's 67.6 (B), and leads in 5 of 7 scored categories. Circle Gateway Nanopayments leads on transparency & trust.

Do Circle Gateway Nanopayments and Tempo need an API key?

Circle Gateway Nanopayments needs no key. Tempo takes an API key or an OAuth sign-in.

Can an agent call Circle Gateway Nanopayments and Tempo without installing anything?

Yes. Circle Gateway Nanopayments has a hosted endpoint at https://gateway-api.circle.com and Tempo at https://api.tempo.xyz/v1.

Are Circle Gateway Nanopayments and Tempo open source?

No open-source release is listed for Circle Gateway Nanopayments. Tempo is open source (MIT OR Apache-2.0).

Other comparisons with Circle Gateway Nanopayments or Tempo

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