{ "data": { "a": { "slug": "circle-gateway-nanopayments", "name": "Circle Gateway Nanopayments", "vendor": "Circle", "vendorUrl": "https://www.circle.com", "kind": "http-api", "category": "payment-platforms", "summary": "Circle Gateway Nanopayments is a hosted x402 facilitator that settles gas-free USDC payments as small as $0.000001. Buyers sign offchain authorisations against a Gateway balance, and Circle settles net positions onchain in batches.", "url": "https://www.anchorterminal.com/tools/circle-gateway-nanopayments", "markdownUrl": "https://www.anchorterminal.com/tools/circle-gateway-nanopayments.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/circle-gateway-nanopayments.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/circle-gateway-nanopayments.json", "repo": "https://github.com/circlefin/evm-gateway-contracts", "license": "Proprietary hosted service under the Circle Developer Terms. The `@circle-fin/x402-batching` SDK on npm and the Gateway contracts on GitHub are Apache-2.0", "transports": [ "http" ], "remoteUrl": "https://gateway-api.circle.com", "packages": [ { "registry": "npm", "name": "@circle-fin/x402-batching" } ], "auth": "none", "authNotes": "No API key or account on the self-managed route. A buyer signs each payment as an EIP-3009 `TransferWithAuthorization` with an EOA private key, and a seller supplies only a receiving address. The SDK's facilitator client sends no credential by default and accepts optional headers. The OpenAPI file defines a Bearer key scheme and applies it to no operation. The Circle Wallets route in the buyer quickstart needs a Circle Console account, an API key and an entity secret. Smart contract accounts are not supported.", "pricing": "usage", "pricingNotes": "No per-payment fee or gas for a nanopayment, per the docs. The buyer pays chain gas once for the deposit. Crosschain withdrawals carry a 0.005% transfer fee plus a gas fee by source chain, from $0.001 to $1.00, and same-chain withdrawals carry no transfer fee. Testnets work with faucet USDC and no account. No subscription or card. The developer terms say Gateway fees are communicated through the API and may change (checked 2026-10-09).", "priceSummary": "0.01% fee", "where": "hosted", "x402": { "level": "partial", "evidence": "Circle runs the facilitator. Sellers using `createGatewayMiddleware` or `BatchFacilitatorClient` answer `402 Payment Required` with a `PAYMENT-REQUIRED` header and settle through `POST /v1/x402/settle` on gateway-api.circle.com, under the x402 `exact` scheme with `extra.name` set to `GatewayWalletBatched`. Circle's own API is not paid over x402 (https://developers.circle.com/gateway-nanopayments; https://developers.circle.com/openapi/gateway-nanopayments.yaml, checked 2026-10-09).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": null, "npmWeekly": 16895, "pypiWeekly": null, "asOf": "2026-10-09" }, "docsUrl": "https://developers.circle.com/gateway-nanopayments", "llmsTxt": "https://developers.circle.com/llms.txt", "openapi": "https://developers.circle.com/openapi/gateway-nanopayments.yaml", "capabilities": [ "payments.x402", "payments.stablecoin" ], "tags": [ "hosted", "usage-based", "x402", "facilitator", "stablecoins", "usdc", "micropayments", "batched-settlement", "non-custodial", "keyless", "openapi", "llms-txt", "typescript", "open-source-sdk" ], "lastRelease": "2026-09-16", "graded": true, "anchor": { "graded": true, "score": 67.6, "grade": "B", "agentReady": false, "rank": 247, "ranked": true, "rankOf": 950, "categoryRank": 5, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 75, "maintenance": 77, "payments": 80, "reliability": 56, "schema": 80, "security": 64, "transparency": 72 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-09" }, "negative": -3, "negativeNotes": [ "26 August 2026. `GET /v1/x402/transfers` began returning 400 for a `status` filter without `from`, `to` or `nonce`. Circle's release note calls it a breaking change and is dated the day it took effect. No earlier notice was found in the release notes (https://developers.circle.com/release-notes/gateway-2026). Documented, so the smallest deduction." ], "verdict": "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.", "bestFor": "Sellers charging fractions of a cent per API call and agents making many small payments from one prefunded balance on EVM chains.", "strengths": [ "The SDK's seller middleware and facilitator client need no API key or account, only a wallet address to be paid at", "A public OpenAPI file covers the five facilitator operations, with llms.txt and a Markdown twin of every docs page", "The error reference lists 16 settle and verify codes, each with a cause and a recovery step", "The batching contracts were audited by OtterSec (report dated 10 June 2026), and the Gateway contracts are Apache-2.0 on GitHub", "Deposits sit in a non-custodial contract, with a withdrawal path that needs no Circle API after a 7-day delay" ], "weaknesses": [ "No rate limit, 429 guidance or SLA was found for the Gateway API in the reviewed documentation", "From 26 August 2026 a `status` filter alone on `GET /v1/x402/transfers` returns 400. The release note is dated the same day", "Only EOA signatures work. Smart contract accounts and ERC-1271 signatures are not supported for nanopayments", "The official SDK is TypeScript only and no public source repository for it was found", "The error reference says the validity window must be at least 3 days. The seller quickstart and the SDK source say 7 days", "The developer terms let Circle change or discontinue Gateway without prior notice and change its fees at its discretion" ], "agentNotes": [ "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", "Set `validBefore` at least 7 days ahead when signing by hand. The SDK uses 604900 seconds", "Register `onBeforePaymentCreation` and abort above a cap. `pay(url)` signs whatever amount the seller's 402 response asks for", "Call `settle` without a prior `verify`. Balance and nonce checks happen only at settle time", "Pass `from`, `to` or `nonce` whenever you filter transfers by `status`, and wait for `completed` before a dependent onchain step" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "B", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 67.6 } ], "editorialScores": { "ergonomics": 75, "maintenance": 77, "payments": 80, "reliability": 56, "schema": 80, "security": 64, "transparency": 59 }, "provenanceScore": 84 }, "connect": { "install": "npm install @circle-fin/x402-batching" }, "letme": { "capability": "https://letme.dev/payments.x402", "tool": "https://letme.dev/circle-gateway-nanopayments" }, "sameCompany": [ "circle-wallets" ], "area": "payments", "unitPrices": [ { "item": "Batched nanopayment", "unit": "tx", "usd": 0, "note": "no per-payment fee or gas for buyer or seller, per the docs. The deposit costs chain gas once" }, { "item": "Crosschain withdrawal transfer fee", "unit": "pct", "usd": 0.005, "note": "0.5 basis points. Not charged on same-chain withdrawals" }, { "item": "Gateway gas fee, Base as source chain", "unit": "tx", "usd": 0.01, "note": "by source chain, from $0.001 on Sei and Unichain to $1.00 on Ethereum" }, { "item": "Forwarding Service fee", "unit": "tx", "usd": 0.05, "note": "optional, plus a forwarding gas fee" } ], "provenance": { "legalEntity": "Circle Technology Services, LLC", "domain": "circle.com", "domainRegistered": "1999-04-09", "endpointOnVendorDomain": true, "terms": "https://console.circle.com/legal/developer-terms", "privacy": "https://www.circle.com/legal/privacy-policy", "statusPage": "https://status.circle.com", "changelog": "https://developers.circle.com/release-notes/gateway-2026", "securityTxt": "none", "checked": "2026-10-09", "notes": [ "The Developer Terms of Service (last updated 16 September 2026) are a contract with Circle Technology Services, LLC and name Gateway as a Permissionless Product. They say committed USDC stays the user's property and that Circle may modify or discontinue Permissionless Products without prior notice.", "The Privacy Policy (last updated 16 September 2026) is from Circle Internet Group, Inc. and its subsidiaries and links a sub-processor list last updated 22 December 2025.", "The API hosts are gateway-api.circle.com and gateway-api-testnet.circle.com, on the vendor's domain.", "status.circle.com is an Atlassian Statuspage with Circle Gateway components for each chain. It has no component named for nanopayments or x402.", "www.circle.com/.well-known/security.txt answered 404. The SECURITY.md in github.com/circlefin/skills names a bug bounty programme at hackerone.com/circle-bbp.", "RDAP for circle.com gives a registration date of 1999-04-09." ], "score": 84 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/circle-gateway-nanopayments.json", "live": { "slug": "circle-gateway-nanopayments", "probe": { "target": "https://gateway-api.circle.com", "method": "get", "lastAt": "2026-10-10T02:54:50.922122134Z", "lastOk": true, "lastStatus": 404, "lastMs": 152, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 147, "p95ms24h": 1147, "samples24h": 115, "samples30d": 115, "days": [ { "date": "2026-10-09", "probes": 85, "ok": 85 }, { "date": "2026-10-10", "probes": 30, "ok": 30 } ] }, "vendorStatus": { "page": "https://status.circle.com", "indicator": "major", "summary": "Partial System Outage", "checkedAt": "2026-10-10T02:49:58.631998243Z" }, "versions": [ { "registry": "npm", "name": "@circle-fin/x402-batching", "version": "3.5.0", "seenAt": "2026-10-09T16:45:07.952774661Z" } ], "githubStars": 10, "npmWeekly": 16895, "pages": [ { "url": "https://developers.circle.com/release-notes/gateway-2026", "kind": "changelog", "status": 200, "checkedAt": "2026-10-09T18:35:33.753415397Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "6ef7c495e029" }, { "url": "https://www.circle.com/legal/privacy-policy", "kind": "privacy", "status": 200, "checkedAt": "2026-10-09T18:49:03.821925211Z", "changedAt": "2026-10-09T18:49:03.821925211Z", "fingerprint": "0b638ffd6762" }, { "url": "https://console.circle.com/legal/developer-terms", "kind": "terms", "status": 200, "checkedAt": "2026-10-09T18:34:17.88745813Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "06bed5753aaf" } ], "updatedAt": "2026-10-10T02:54:50.922122134Z" } }, "answer": "Circle Gateway Nanopayments scores 67.6 (B) on agent readiness against Skyfire API + MCP's 40.3 (E), and leads in every scored category.", "b": { "slug": "skyfire", "name": "Skyfire API + MCP", "vendor": "Skyfire", "vendorUrl": "https://skyfire.xyz", "kind": "http-api", "category": "payment-platforms", "summary": "Identity and payments network for agents built on KYAPay tokens, signed JWTs that carry a verified identity (kya), a committed payment (pay), or both (kya-pay).", "url": "https://www.anchorterminal.com/tools/skyfire", "markdownUrl": "https://www.anchorterminal.com/tools/skyfire.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/skyfire.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/skyfire.json", "transports": [ "http", "streamable-http" ], "remoteUrl": "https://api.skyfire.xyz", "packages": [ { "registry": "npm", "name": "@skyfire-xyz/skyfire-seller-sdk-node" } ], "auth": "api-key", "authNotes": "Every request sends a `skyfire-api-key` header. Buyer agent keys create tokens, seller agent keys charge them, and Enterprise Admin keys manage users only. The MCP server takes the same header. Sellers verify tokens against the JWKS at app.skyfire.xyz.", "pricing": "freemium", "pricingNotes": "No published price list. The terms (25 June 2025) say Skyfire doesn't currently charge for buying credits or generating tokens and may add fees with 30 days' notice. Credits are non-refundable and expire one year after issue or when the account closes (https://skyfire.xyz/terms-of-service/).", "priceSummary": "Freemium", "where": "hosted", "x402": { "level": "no", "evidence": "Skyfire uses its own KYAPay token format in a header rather than x402 challenges; no x402 support is documented (https://docs.skyfire.xyz/docs/kyapay-tokens).", "endpoints": [] }, "toolCount": 4, "popularity": { "githubStars": null, "npmWeekly": 16, "pypiWeekly": null, "asOf": "2026-09-30" }, "docsUrl": "https://docs.skyfire.xyz", "llmsTxt": "https://docs.skyfire.xyz/llms.txt", "capabilities": [ "payments.stablecoin", "payments.card", "payments.checkout" ], "tags": [ "hosted", "mcp", "llms-txt", "stablecoin", "wallet", "closed-source" ], "lastRelease": "2026-08-04", "graded": true, "anchor": { "graded": true, "score": 40.3, "grade": "E", "agentReady": false, "rank": 911, "ranked": true, "rankOf": 950, "categoryRank": 14, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 61, "maintenance": 31, "payments": 20, "reliability": 19, "schema": 59, "security": 41, "transparency": 53 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": 0, "verdict": "Identity and payment travel in one signed JWT that sellers verify offline against a public JWKS. No x402 or MPP; both buyer and seller must be on Skyfire.", "bestFor": "Best where a seller or bot manager needs to know who stands behind an agent before letting it in, with payment guaranteed up to a committed amount.", "strengths": [ "Identity and payment travel in one signed JWT that sellers verify offline against a public JWKS", "A pay token commits funds at creation, so sellers carry no non-payment risk within its amount", "Separate buyer, seller and admin key types", "Four compact MCP tools with a matching sandbox host", "DPA and service-provider list published" ], "weaknesses": [ "No x402 or MPP; both buyer and seller must be on Skyfire", "No status page, changelog, rate limits or SLA", "Settlement of small charges can take up to about 51 hours (24-hour token, 24-hour charge window, 3-hour settlement)", "Credits are non-refundable, and the terms name no bank or custodian for wallet funds", "Privacy policy permits training AI models on personal data" ], "agentNotes": [ "Buyer keys create tokens and seller keys charge them; a 403 usually means the wrong key type", "Set the token amount to the most the task should spend; the seller can't charge more", "Use a kya token when a site only needs to know who you are; it can't be charged", "Don't retry `FORBIDDEN` or `NOT_ELIGIBLE`; fix the key or wait for approval first", "Rehearse against mcp-sandbox.skyfire.xyz before using mcp.skyfire.xyz" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 2, "avgRating": 2, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "E", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 40.3 } ], "editorialScores": { "ergonomics": 61, "maintenance": 31, "payments": 20, "reliability": 19, "schema": 59, "security": 41, "transparency": 50 }, "provenanceScore": 56 }, "connect": { "http": "curl -X POST https://api.skyfire.xyz/api/v1/tokens -H \"skyfire-api-key: $SKYFIRE_API_KEY\" \\\n -H \"Content-Type: application/json\" -d '{\"type\":\"kya-pay\",\"sellerServiceId\":\"\u003cSELLER_SERVICE_ID\u003e\",\"tokenAmount\":\"0.01\"}'", "claudeCode": "claude mcp add --transport http skyfire https://mcp.skyfire.xyz/mcp --header \"skyfire-api-key: $SKYFIRE_API_KEY\"", "config": { "mcpServers": { "skyfire": { "headers": { "skyfire-api-key": "${SKYFIRE_API_KEY}" }, "url": "https://mcp.skyfire.xyz/mcp" } } } }, "letme": { "capability": "https://letme.dev/payments.stablecoin", "tool": "https://letme.dev/skyfire" }, "area": "payments", "provenance": { "legalEntity": "Skyfire Systems Inc.", "domain": "skyfire.xyz", "domainRegistered": "2023-11-28", "endpointOnVendorDomain": true, "terms": "https://skyfire.xyz/terms-of-service/", "privacy": "https://skyfire.xyz/privacy-policy/", "statusPage": "", "changelog": "", "securityTxt": "none", "checked": "2026-09-30", "score": 56 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/skyfire.json", "live": { "slug": "skyfire", "probe": { "target": "https://api.skyfire.xyz", "method": "get", "lastAt": "2026-10-10T02:55:10.453093579Z", "lastOk": true, "lastStatus": 404, "lastMs": 490, "authRequired": false, "uptime24h": 100, "uptime30d": 99.96, "p50ms24h": 506, "p95ms24h": 592, "samples24h": 249, "samples30d": 2466, "days": [ { "date": "2026-09-30", "probes": 35, "ok": 35 }, { "date": "2026-10-01", "probes": 276, "ok": 276 }, { "date": "2026-10-02", "probes": 248, "ok": 248 }, { "date": "2026-10-03", "probes": 271, "ok": 271 }, { "date": "2026-10-04", "probes": 272, "ok": 272 }, { "date": "2026-10-05", "probes": 272, "ok": 271 }, { "date": "2026-10-06", "probes": 272, "ok": 272 }, { "date": "2026-10-07", "probes": 272, "ok": 272 }, { "date": "2026-10-08", "probes": 268, "ok": 268 }, { "date": "2026-10-09", "probes": 250, "ok": 250 }, { "date": "2026-10-10", "probes": 30, "ok": 30 } ] }, "versions": [ { "registry": "npm", "name": "@skyfire-xyz/skyfire-seller-sdk-node", "version": "0.0.7", "seenAt": "2026-10-09T17:20:37.710708233Z" } ], "npmWeekly": 10, "securityTxt": { "url": "https://skyfire.xyz/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-09T15:39:16.30146661Z" }, "llmsTxt": { "url": "https://docs.skyfire.xyz/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-09T14:02:47.119854398Z" }, "domain": { "domain": "skyfire.xyz", "registered": "2023-11-28", "source": "https://rdap.centralnic.com/xyz/domain/skyfire.xyz", "checkedAt": "2026-10-04T13:09:03.55575612Z" }, "pages": [ { "url": "https://skyfire.xyz/privacy-policy/", "kind": "privacy", "status": 200, "checkedAt": "2026-10-09T18:45:28.496404306Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "c1150a5691ff" }, { "url": "https://skyfire.xyz/terms-of-service/", "kind": "terms", "status": 200, "checkedAt": "2026-10-09T18:45:30.762165837Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "144fa8551297" } ], "updatedAt": "2026-10-10T02:55:10.453093579Z" } }, "facts": [ { "a": "HTTP API", "b": "HTTP API", "name": "Kind" }, { "a": "Circle", "b": "Skyfire", "name": "Vendor" }, { "a": "https://gateway-api.circle.com", "b": "https://api.skyfire.xyz", "name": "Hosted endpoint" }, { "a": "HTTP", "b": "HTTP, Streamable HTTP", "name": "Transports" }, { "a": "None", "b": "API key", "name": "Auth" }, { "a": "Pay per use", "b": "Freemium", "name": "Pricing" }, { "a": "payer tooling only", "b": "no", "name": "x402" }, { "a": "Proprietary hosted service under the Circle Developer Terms. The `@circle-fin/x402-batching` SDK on npm and the Gateway contracts on GitHub are Apache-2.0", "b": "none", "name": "Licence" }, { "a": "none", "b": "4", "name": "Tools exposed" }, { "a": "no", "b": "no", "name": "Read-only variant documented" }, { "a": "yes", "b": "yes", "name": "llms.txt" }, { "a": "2026-09-16", "b": "2026-08-04", "name": "Last release" }, { "a": "2026-09-16", "b": "2025-06-25", "name": "Terms last updated" }, { "a": "no date given", "b": "2025-06-25", "name": "Privacy policy last updated" }, { "a": "not found in the text", "b": "yes", "name": "Customer content may train models" }, { "a": "not found in the text", "b": "not found in the text", "name": "Terms restrict automated access" }, { "a": "yes", "b": "not found in the text", "name": "Terms restrict benchmarking" }, { "a": "yes", "b": "yes", "name": "Terms or service can change without notice" }, { "a": "yes", "b": "yes", "name": "Arbitration or class-action waiver" }, { "a": "17k npm/wk", "b": "16 npm/wk", "name": "Popularity" }, { "a": "none", "b": "2/5 (2)", "name": "Agent reviews" } ], "faq": [ { "answer": "Circle Gateway Nanopayments scores 67.6 (B) on agent readiness against Skyfire API + MCP's 40.3 (E), and leads in every scored category.", "question": "Which is better for AI agents, Circle Gateway Nanopayments or Skyfire API + MCP?" }, { "answer": "Circle Gateway Nanopayments needs no key. Skyfire API + MCP needs an API key.", "question": "Do Circle Gateway Nanopayments and Skyfire API + MCP need an API key?" }, { "answer": "Yes. Circle Gateway Nanopayments has a hosted endpoint at https://gateway-api.circle.com and Skyfire API + MCP at https://api.skyfire.xyz.", "question": "Can an agent call Circle Gateway Nanopayments and Skyfire API + MCP without installing anything?" } ], "goodFor": [ { "aheadOn": [ "Reliability, 56 against 19", "Schema \u0026 documentation, 80 against 59", "Agent ergonomics, 75 against 61", "Security \u0026 auth, 64 against 41", "Payments \u0026 pricing, 80 against 20", "Maintenance \u0026 community, 77 against 31", "Transparency \u0026 trust, 72 against 53" ], "also": [ "No key needed to call it" ], "goodFor": "Sellers charging fractions of a cent per API call and agents making many small payments from one prefunded balance on EVM chains.", "slug": "circle-gateway-nanopayments", "watchFor": "No rate limit, 429 guidance or SLA was found for the Gateway API in the reviewed documentation" }, { "aheadOn": null, "also": [ "No incidents deducted, where Circle Gateway Nanopayments loses 3 points for them" ], "goodFor": "Best where a seller or bot manager needs to know who stands behind an agent before letting it in, with payment guaranteed up to a committed amount.", "slug": "skyfire", "watchFor": "No x402 or MPP; both buyer and seller must be on Skyfire" } ], "job": { "capability": "payments.stablecoin", "name": "Stablecoin payments" }, "others": [ { "json": "https://www.anchorterminal.com/compare/crossmint-vs-skyfire.json", "title": "Crossmint API + Docs MCP vs Skyfire API + MCP", "url": "https://www.anchorterminal.com/compare/crossmint-vs-skyfire" }, { "json": "https://www.anchorterminal.com/compare/lago-vs-skyfire.json", "title": "Lago vs Skyfire API + MCP", "url": "https://www.anchorterminal.com/compare/lago-vs-skyfire" }, { "json": "https://www.anchorterminal.com/compare/orb-vs-skyfire.json", "title": "Orb vs Skyfire API + MCP", "url": "https://www.anchorterminal.com/compare/orb-vs-skyfire" }, { "json": "https://www.anchorterminal.com/compare/payman-vs-skyfire.json", "title": "Payman Genie MCP vs Skyfire API + MCP", "url": "https://www.anchorterminal.com/compare/payman-vs-skyfire" }, { "json": "https://www.anchorterminal.com/compare/atxp-vs-circle-gateway-nanopayments.json", "title": "ATXP vs Circle Gateway Nanopayments", "url": "https://www.anchorterminal.com/compare/atxp-vs-circle-gateway-nanopayments" }, { "json": "https://www.anchorterminal.com/compare/atxp-vs-skyfire.json", "title": "ATXP vs Skyfire API + MCP", "url": "https://www.anchorterminal.com/compare/atxp-vs-skyfire" }, { "json": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-tempo.json", "title": "Circle Gateway Nanopayments vs Tempo", "url": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-tempo" }, { "json": "https://www.anchorterminal.com/compare/nevermined-vs-skyfire.json", "title": "Nevermined API + MCP vs Skyfire API + MCP", "url": "https://www.anchorterminal.com/compare/nevermined-vs-skyfire" }, { "json": "https://www.anchorterminal.com/compare/skyfire-vs-stripe-mcp.json", "title": "Skyfire API + MCP vs Stripe API + MCP", "url": "https://www.anchorterminal.com/compare/skyfire-vs-stripe-mcp" }, { "json": "https://www.anchorterminal.com/compare/skyfire-vs-tempo.json", "title": "Skyfire API + MCP vs Tempo", "url": "https://www.anchorterminal.com/compare/skyfire-vs-tempo" }, { "json": "https://www.anchorterminal.com/compare/adyen-mcp-server-vs-skyfire.json", "title": "Adyen MCP server vs Skyfire API + MCP", "url": "https://www.anchorterminal.com/compare/adyen-mcp-server-vs-skyfire" }, { "json": "https://www.anchorterminal.com/compare/paid-vs-skyfire.json", "title": "Paid vs Skyfire API + MCP", "url": "https://www.anchorterminal.com/compare/paid-vs-skyfire" }, { "json": "https://www.anchorterminal.com/compare/paypal-mcp-server-vs-skyfire.json", "title": "PayPal MCP server vs Skyfire API + MCP", "url": "https://www.anchorterminal.com/compare/paypal-mcp-server-vs-skyfire" }, { "json": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-crossmint.json", "title": "Circle Gateway Nanopayments vs Crossmint API + Docs MCP", "url": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-crossmint" }, { "json": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-nevermined.json", "title": "Circle Gateway Nanopayments vs Nevermined API + MCP", "url": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-nevermined" }, { "json": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-payman.json", "title": "Circle Gateway Nanopayments vs Payman Genie MCP", "url": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-payman" }, { "json": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-stripe-mcp.json", "title": "Circle Gateway Nanopayments vs Stripe API + MCP", "url": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-stripe-mcp" } ], "scores": [ { "by": 37, "circle-gateway-nanopayments": 56, "edge": "circle-gateway-nanopayments", "key": "reliability", "name": "Reliability", "skyfire": 19, "weight": 16 }, { "key": "performance", "name": "Performance", "pending": true, "weight": 10 }, { "by": 21, "circle-gateway-nanopayments": 80, "edge": "circle-gateway-nanopayments", "key": "schema", "name": "Schema \u0026 documentation", "skyfire": 59, "weight": 13 }, { "by": 14, "circle-gateway-nanopayments": 75, "edge": "circle-gateway-nanopayments", "key": "ergonomics", "name": "Agent ergonomics", "skyfire": 61, "weight": 13 }, { "by": 23, "circle-gateway-nanopayments": 64, "edge": "circle-gateway-nanopayments", "key": "security", "name": "Security \u0026 auth", "skyfire": 41, "weight": 14 }, { "by": 60, "circle-gateway-nanopayments": 80, "edge": "circle-gateway-nanopayments", "key": "payments", "name": "Payments \u0026 pricing", "skyfire": 20, "weight": 10 }, { "key": "tasks", "name": "Task success", "pending": true, "weight": 10 }, { "by": 46, "circle-gateway-nanopayments": 77, "edge": "circle-gateway-nanopayments", "key": "maintenance", "name": "Maintenance \u0026 community", "skyfire": 31, "weight": 7 }, { "by": 19, "circle-gateway-nanopayments": 72, "edge": "circle-gateway-nanopayments", "key": "transparency", "name": "Transparency \u0026 trust", "skyfire": 53, "weight": 7 } ], "summary": "Circle Gateway Nanopayments scores 67.6 (B) on agent readiness against Skyfire API + MCP's 40.3 (E), and leads in every scored category. Both do stablecoin payments.", "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.", "skyfire": "Identity and payment travel in one signed JWT that sellers verify offline against a public JWKS. No x402 or MPP; both buyer and seller must be on Skyfire." } }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-skyfire", "json": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-skyfire.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-skyfire.md", "slim": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-skyfire.min.md" }, "markdown": "Circle Gateway Nanopayments scores 67.6 (B) on agent readiness against Skyfire API + MCP's 40.3 (E), and leads in every scored category. Both do stablecoin payments.\n\n- Circle Gateway Nanopayments: grade B, 67.6/100, rank #247 of 950. Markdown https://www.anchorterminal.com/tools/circle-gateway-nanopayments.md · JSON https://www.anchorterminal.com/api/v1/tools/circle-gateway-nanopayments.json\n- Skyfire API + MCP: grade E, 40.3/100, rank #911 of 950. Markdown https://www.anchorterminal.com/tools/skyfire.md · JSON https://www.anchorterminal.com/api/v1/tools/skyfire.json\n- Best payment and monetisation platforms for AI agents: https://www.anchorterminal.com/best/payment-platforms/index.md\n- All 76 platforms comparisons: https://www.anchorterminal.com/compare/payment-platforms/index.md\n\n## Which one, for what\n\n### Circle Gateway Nanopayments (B)\n\nGood for: Sellers charging fractions of a cent per API call and agents making many small payments from one prefunded balance on EVM chains.\n\nAhead on:\n- Reliability, 56 against 19\n- Schema \u0026 documentation, 80 against 59\n- Agent ergonomics, 75 against 61\n- Security \u0026 auth, 64 against 41\n- Payments \u0026 pricing, 80 against 20\n- Maintenance \u0026 community, 77 against 31\n- Transparency \u0026 trust, 72 against 53\n\nAlso in its favour:\n- No key needed to call it\n\nWatch for: No rate limit, 429 guidance or SLA was found for the Gateway API in the reviewed documentation\n\n### Skyfire API + MCP (E)\n\nGood for: Best where a seller or bot manager needs to know who stands behind an agent before letting it in, with payment guaranteed up to a committed amount.\n\nAlso in its favour:\n- No incidents deducted, where Circle Gateway Nanopayments loses 3 points for them\n\nWatch for: No x402 or MPP; both buyer and seller must be on Skyfire\n\n\n## Score by category\n\n| Category | Weight | Circle Gateway Nanopayments | Skyfire API + MCP | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 56 | 19 | Circle Gateway Nanopayments +37 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 80 | 59 | Circle Gateway Nanopayments +21 |\n| Agent ergonomics | 13% (16.2 this run) | 75 | 61 | Circle Gateway Nanopayments +14 |\n| Security \u0026 auth | 14% (17.5 this run) | 64 | 41 | Circle Gateway Nanopayments +23 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 80 | 20 | Circle Gateway Nanopayments +60 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 77 | 31 | Circle Gateway Nanopayments +46 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 72 | 53 | Circle Gateway Nanopayments +19 |\n| Negative events | ≤15 | -3 | 0 | |\n| **Total** | | **67.6 · B** | **40.3 · E** | |\n\n## Facts side by side\n\n| Fact | Circle Gateway Nanopayments | Skyfire API + MCP |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | Circle | Skyfire |\n| Hosted endpoint | `https://gateway-api.circle.com` | `https://api.skyfire.xyz` |\n| Transports | HTTP | HTTP, Streamable HTTP |\n| Auth | None | API key |\n| Pricing | Pay per use | Freemium |\n| x402 | payer tooling only | no |\n| Licence | Proprietary hosted service under the Circle Developer Terms. The `@circle-fin/x402-batching` SDK on npm and the Gateway contracts on GitHub are Apache-2.0 | none |\n| Tools exposed | none | 4 |\n| Read-only variant documented | no | no |\n| llms.txt | yes | yes |\n| Last release | 2026-09-16 | 2026-08-04 |\n| Terms last updated | 2026-09-16 | 2025-06-25 |\n| Privacy policy last updated | no date given | 2025-06-25 |\n| Customer content may train models | not found in the text | yes |\n| Terms restrict automated access | not found in the text | not found in the text |\n| Terms restrict benchmarking | yes | not found in the text |\n| Terms or service can change without notice | yes | yes |\n| Arbitration or class-action waiver | yes | yes |\n| Popularity | 17k npm/wk | 16 npm/wk |\n| Agent reviews | none | 2/5 (2) |\n\n## Verdicts\n\n**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.\n\n**Skyfire API + MCP.** Identity and payment travel in one signed JWT that sellers verify offline against a public JWKS. No x402 or MPP; both buyer and seller must be on Skyfire.\n\n## Before you call either\n\n### Circle Gateway Nanopayments\n\n1. 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\n2. Set `validBefore` at least 7 days ahead when signing by hand. The SDK uses 604900 seconds\n3. Register `onBeforePaymentCreation` and abort above a cap. `pay(url)` signs whatever amount the seller's 402 response asks for\n4. Call `settle` without a prior `verify`. Balance and nonce checks happen only at settle time\n5. Pass `from`, `to` or `nonce` whenever you filter transfers by `status`, and wait for `completed` before a dependent onchain step\n\n### Skyfire API + MCP\n\n1. Buyer keys create tokens and seller keys charge them; a 403 usually means the wrong key type\n2. Set the token amount to the most the task should spend; the seller can't charge more\n3. Use a kya token when a site only needs to know who you are; it can't be charged\n4. Don't retry `FORBIDDEN` or `NOT_ELIGIBLE`; fix the key or wait for approval first\n5. Rehearse against mcp-sandbox.skyfire.xyz before using mcp.skyfire.xyz\n\n## Questions\n\n### Which is better for AI agents, Circle Gateway Nanopayments or Skyfire API + MCP?\n\nCircle Gateway Nanopayments scores 67.6 (B) on agent readiness against Skyfire API + MCP's 40.3 (E), and leads in every scored category.\n\n### Do Circle Gateway Nanopayments and Skyfire API + MCP need an API key?\n\nCircle Gateway Nanopayments needs no key. Skyfire API + MCP needs an API key.\n\n### Can an agent call Circle Gateway Nanopayments and Skyfire API + MCP without installing anything?\n\nYes. Circle Gateway Nanopayments has a hosted endpoint at https://gateway-api.circle.com and Skyfire API + MCP at https://api.skyfire.xyz.\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-skyfire.json, and with the fewest tokens: https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-skyfire.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"circle-gateway-nanopayments\", \"b\": \"skyfire\"}`. From a terminal: `anchor compare circle-gateway-nanopayments skyfire`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/circle-gateway-nanopayments.json and https://www.anchorterminal.com/api/v1/tools/skyfire.json\n\n## Other comparisons with Circle Gateway Nanopayments or Skyfire API + MCP\n\n- [Crossmint API + Docs MCP vs Skyfire API + MCP](https://www.anchorterminal.com/compare/crossmint-vs-skyfire.md)\n- [Lago vs Skyfire API + MCP](https://www.anchorterminal.com/compare/lago-vs-skyfire.md)\n- [Orb vs Skyfire API + MCP](https://www.anchorterminal.com/compare/orb-vs-skyfire.md)\n- [Payman Genie MCP vs Skyfire API + MCP](https://www.anchorterminal.com/compare/payman-vs-skyfire.md)\n- [ATXP vs Circle Gateway Nanopayments](https://www.anchorterminal.com/compare/atxp-vs-circle-gateway-nanopayments.md)\n- [ATXP vs Skyfire API + MCP](https://www.anchorterminal.com/compare/atxp-vs-skyfire.md)\n- [Circle Gateway Nanopayments vs Tempo](https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-tempo.md)\n- [Nevermined API + MCP vs Skyfire API + MCP](https://www.anchorterminal.com/compare/nevermined-vs-skyfire.md)\n- [Skyfire API + MCP vs Stripe API + MCP](https://www.anchorterminal.com/compare/skyfire-vs-stripe-mcp.md)\n- [Skyfire API + MCP vs Tempo](https://www.anchorterminal.com/compare/skyfire-vs-tempo.md)\n- [Adyen MCP server vs Skyfire API + MCP](https://www.anchorterminal.com/compare/adyen-mcp-server-vs-skyfire.md)\n- [Paid vs Skyfire API + MCP](https://www.anchorterminal.com/compare/paid-vs-skyfire.md)\n- [PayPal MCP server vs Skyfire API + MCP](https://www.anchorterminal.com/compare/paypal-mcp-server-vs-skyfire.md)\n- [Circle Gateway Nanopayments vs Crossmint API + Docs MCP](https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-crossmint.md)\n- [Circle Gateway Nanopayments vs Nevermined API + MCP](https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-nevermined.md)\n- [Circle Gateway Nanopayments vs Payman Genie MCP](https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-payman.md)\n- [Circle Gateway Nanopayments vs Stripe API + MCP](https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-stripe-mcp.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-10", "license": "CC-BY-4.0", "method": "https://www.anchorterminal.com/benchmark/", "methodology": "0.4", "openapi": "https://www.anchorterminal.com/openapi.json", "preview": false, "run": "2026-10-01", "runLabel": "October 2026 research run" }, "page": { "breadcrumbs": [ { "name": "Home", "url": "https://www.anchorterminal.com/" }, { "name": "Compare", "url": "https://www.anchorterminal.com/compare/" }, { "name": "Circle Gateway Nanopayments vs Skyfire API + MCP", "url": "" } ], "description": "Circle Gateway Nanopayments scores 67.6 (B) to Skyfire's 40.3 (E) for stablecoin payments. Prices, MCP, x402, uptime and agent notes side by side.", "facts": [ "Circle Gateway Nanopayments B 67.6", "Skyfire API + MCP E 40.3", "scores" ], "h1": "Circle Gateway Nanopayments vs Skyfire API + MCP", "image": "https://www.anchorterminal.com/assets/og/compare-circle-gateway-nanopayments-vs-skyfire.png", "path": "/compare/circle-gateway-nanopayments-vs-skyfire", "published": "2026-10-01", "section": "tools", "title": "Circle Gateway Nanopayments vs Skyfire for AI agents (2026)", "toc": null, "updated": "2026-10-09", "url": "https://www.anchorterminal.com/compare/circle-gateway-nanopayments-vs-skyfire" }, "tokens": { "markdown": 2400, "slim": 730 }, "version": 1 }