Circle Gateway Nanopayments vs FluxA AI Wallet

Circle Gateway Nanopayments 66

Graded as a hosted service on gateway-api.circle.com. status.circle.com is a Statuspage with Circle Gateway components for each chain, mainnet and testnet (20). The history pages, read on 1 November 2026, list every incident from June to 31 October. From 3 August none names Gateway or a Gateway component. They cover USDC mints on single chains, CCTP attestations, xReserve, Wallets and testnets, and the two HyperEVM incidents opened name only CCTP and USDC components. The last Gateway incident was testnet only, 29 June to 2 July, outside the window. A clean record (30). No rate limit with numbers was found for the Gateway API, and an unauthenticated call to /v1/x402/supported carried no rate-limit headers (0). No 429 or Retry-After guidance was found. Each authorisation carries a unique nonce, a repeat returns nonce_already_used, and the error reference says to retry unexpected_error (6 of 15). No SLA was found, and the developer terms allow changes without prior notice (0). The release notes record the mainnet launch on 29 April 2026 and the pages read carry no beta label (10).

FluxA AI Wallet 20

Graded with the hosted lines, because signing, mandates and approvals all run on FluxA's wallet API and the CLI and MCP server only wrap it, as kite-agent-passport and kane-cli were read. No status page was found in the repository, the skills or AgentMarket's pages. fluxapay.xyz and the wallet and docs hosts could not be read, so a status page there is unchecked and scored absent (0). With no readable history the record takes the default (5). No rate limit with numbers was found (0). The connection service treats 429 slow_down as wait and poll and marks errors retryable, the skill says a 503 means retry shortly, payouts require a caller-chosen payout_id that returns the existing payout on a repeat, --biz-id rejects a duplicate with 409, and card create and recharge resume with --request-id instead of paying again. No Retry-After or backoff schedule is documented for the wallet API (10 of 15). No SLA was found (0). No beta label was found on the wallet in what was read, but both packages are at 0.x, agent cards sit behind a waitlist and the wallet site was unread (5 of 10). Total 20.

Circle Gateway Nanopayments 73

The SDK is Apache-2.0 on npm and the Gateway contracts are Apache-2.0 on GitHub. The API service and the enclave code are closed, under clear developer terms (22 of 30). The privacy policy of 16 September 2026 lists transaction and blockchain data among what is collected and keeps data as long as necessary, with no periods. The service terms link a DPA dated 2022. Nothing found says what the Gateway API logs about a payment (17 of 30). The developer terms promise reasonable efforts to announce the end of support for a version and also let Circle modify or discontinue Gateway without prior notice. The one breaking change found was noted on the day it took effect (6 of 20). A sub-processor list, last updated 22 December 2025, names each processor with its purpose and country (14 of 20).

FluxA AI Wallet 32

The CLI and MCP server source is Apache-2.0 per the LICENSE file and both package.json files, while the README's last section says MIT. The hosted wallet is closed, and no terms covering it were found. AgentMarket's terms describe only the marketplace (15 of 30). AgentMarket's privacy policy of 14 January 2026 names Stripe and model providers and gives no retention periods, and it does not mention wallet addresses, KYC profiles, card data or payouts, which the CLI collects or handles. The wallet's own privacy policy was unreachable (5 of 30). The README marks init and link-wallet as legacy but still supported, and the skill pins a minimum CLI version; no deprecation policy or dated notice was found (3 of 20). Stripe is the only provider named; no card issuer, KYC provider, custody provider or data location is named. The CLI and MCP code send no telemetry (3 of 20). Total 26.

Circle Gateway Nanopayments 80

Payment platforms and wallets take the highest step that applies on the 40-point protocol line. 40 for x402, MPP or L402 on all their own endpoints, 30 on part of their own API, 25 when their merchants can accept one, 20 for running a facilitator, 15 for paying as a buyer, 0 for only a protocol of their own. Circle's own API is not paid over x402. Sellers accept x402 through Circle's middleware and facilitator, so the merchant step. An unpaid call to GET /v1/x402/supported on 1 November returned 200 with 12 mainnet networks, each x402 version 2, scheme exact and GatewayWalletBatched (25 of 40). The fee page is public with no login, 0.005% on crosschain withdrawals plus a gas fee by chain, and the docs say a nanopayment costs neither party a fee. No price list states the nanopayment fee as a figure, and the terms say fees are communicated through the API and may change (15 of 20). Testnets run on faucet USDC with no account or card, and mainnet has no subscription (20). An agent holding an EOA key and USDC can deposit and pay with no signup, and a seller needs only an address (20).

FluxA AI Wallet 45

Payment platforms and wallets take the highest step that applies on the 40-point protocol line. 40 for x402, MPP or L402 on all their own endpoints, 30 on part of their own API, 25 when their merchants can accept one, 20 for running a facilitator, 15 for paying as a buyer, 0 for only a protocol of their own. The wallet pays x402 as a buyer and its payment links can be paid over x402 so another agent pays the holder, as sponge-wallet's payment links were read. FluxA's own wallet API is not paid over x402, so the merchant step (25 of 40). No fee schedule for the wallet, x402 signing, payouts or payment links was found, and card fees appear only through an authenticated command (0 of 20). Registering an Agent ID and creating payment links cost nothing and need no card per the README and the charge-agent guide, but the wallet sign-up at agentwallet.fluxapay.xyz could not be read, so whether opening a funded wallet needs a card is unchecked (10 of 20). POST https://agentid.fluxapay.xyz/register returns credentials with no human step, but the CLI marks it legacy, the default connection needs a browser approval, and every spend needs the owner's wallet and a mandate signed in a browser (10 of 20). Total 45.

Circle Gateway Nanopayments 80

A public OpenAPI 3.0.3 file covers the five operations. It gives the 400 responses no body schema and attaches its Bearer scheme to no operation (23 of 25). llms.txt and a Markdown twin of every docs page (10). The docs say when to use this facilitator and when Circle's other one, and to call settle without verify in production (15 of 20). Transfer status and settle error reasons are enums and required fields are marked. payload, extra and extensions are open objects, and pageSize has no maximum (10 of 15). Every SDK method has a typed signature and an example, and 16 API error codes have a cause and a recovery step. The error reference says the validity window must be 3 days where the quickstart, the SDK and the live minValiditySeconds of 604800 say 7 (11 of 15). Paths are under /v1, the SDK follows semver and the release notes are dated. The npm package ships no changelog (11 of 15).

FluxA AI Wallet 61

No OpenAPI file or reference for the wallet API was found; the README shows sample requests for five endpoints. The MCP server's 15 tools in the 0.6.0 source carry typed Zod input schemas, and the CLI's flags are documented in prose in the skill files and --help. The MCP server is the secondary surface and its npm release is 0.2.0, so 12 of 25. The skill and its 18 Markdown guides are written for agents, and AgentMarket's llms.txt describes the wallet's payment role (10). connect_wallet, init_agent_id and create_intent_mandate say when to use them and when not to, and the skill has a when-to-use table per capability, while the payment-link and status tools have one-line descriptions (12 of 20). Zod enums for validity, runtime, hosting and currency, a regex on payout amounts and strict objects, but the x402 requirement fields are plain strings and outputSchema is a free-form record (10 of 15). The README has an example for every MCP tool, the skills give CLI examples and output, and error codes are tabled for mandates, payouts, cards and connections (12 of 15). Semver on npm with 25 CLI versions and a version line in the skill, two git tags and no changelog (5 of 15). Total 61.

Circle Gateway Nanopayments 75

The API is five operations and the buyer path is one pay(url) call. Transfer search takes pageSize (20 of 25). Cursor pagination with pageAfter and pageBefore, and filters by sender, recipient, nonce, network, status and date. A status filter needs a second filter since 26 August 2026 (17 of 20). Sixteen error codes with recovery steps, and typed SDK error messages (17 of 20). The nonce stops one authorisation being settled twice and a completed or failed state tells a caller when to stop. No idempotency key was found, and a failed payment needs a newly signed authorisation (13 of 20). The seller middleware needs one address and a price, and the buyer client a chain and a key. The only official SDK is TypeScript (8 of 15).

FluxA AI Wallet 60

The MCP server has 15 tools with about 4,700 characters of descriptions, the 11 to 30 band (15). The CLI path loads SKILL.md (26.5 KB) and one of 18 guides per task, about 112 KB in all, with no read-only subset (no add-back, 15 of 25). card transactions takes page, limit, type and a time range, refunds take limit and offset, received-records and recent-transactions take a limit up to 100, and market search can be scoped to models or vendors; no cursor (12 of 20). Errors carry a code, retryable, reconnect_required and a next_command or next_tool, and card errors map to recovery hints, but the CLI exits only 0 or 1 and the MCP payment tools return the wallet API's raw error body without isError (14 of 20). A required payout_id idempotency key, --biz-id dedup and --request-id continuation on card operations, and the skill says not to initiate again to retry a payment. No readOnlyHint or destructiveHint on any MCP tool (12 of 20). Base USDC is the default network and asset, mandates default to 8 hours and the CLI installs in one command, but there is no SDK library and both packages are TypeScript (7 of 15). Total 60.

Circle Gateway Nanopayments 64

No API key. The buyer's EOA private key signs each payment, and each authorisation is bound to one amount, recipient, validity window and nonce. The same key controls the whole wallet, the SDK takes it as a plain config value, and smart contract accounts with their own policies are not supported (18 of 30). Only the deposited Gateway balance can be spent, and a client hook can abort a payment above a limit. No limit is set by default and none is enforced by the service (12 of 20). The amount comes from the seller's 402 response, which is untrusted. The docs show the spending-limit hook and give no other guidance. Circle's Gateway skill file says to ask the user before moving funds on mainnet (8 of 15). Transfers can be searched by address, nonce and date and each carries its batch transaction hash. No separate operator log was found (11 of 15). Audit reports by ChainSecurity and OtterSec are linked, one of them on batching, and a repository security policy names a HackerOne bug bounty programme. security.txt answered 404 and no certification was found on the pages read (15 of 20).

FluxA AI Wallet 52

The agent holds an Agent ID, a token whose validity the owner picks from 1 hour to 1 year at browser approval, and a short-lived RS256 JWT refreshed from the token; token_revoked exists. Credentials sit in a 0600 JSON file or environment variables. The token is not scoped, since limits live in mandates, and legacy init tokens are described as not expiring. Agent VCs are audience-bound and rejected by FluxA's own endpoints. No secret travels in a URL (22 of 30). Every x402 payment needs a mandate the owner signs, with a limit, a validity and an optional host allowlist enforced by the wallet API, payouts need per-payout approval unless a mandate covers them, cards need a mandate and KYC, and linked-card mandates are scoped to one merchant. A payout mandate sets no payee allowlist that was documented, and the skill tells agents to request budgets for at least 100 calls by default (16 of 20). The wallet returns little third-party content itself, but the skill sends agents to third-party x402 APIs, ClawPI posts and a remote announcement.md with no guidance on treating them as untrusted, its description steers agents to paid APIs even when a free web search looks enough, and the daily check-in runs npx -y @fluxa-pay/fluxa-wallet@latest unpinned twice a day (4 of 15). mandates lists limit, spent and remaining, with recent-transactions, received-records and payout status by CLI, and the MCP server writes a local audit log; the wallet app's logs were not read (10 of 15). No SECURITY.md, disclosure policy, bug bounty or certification was found, and agentmarket.fluxapay.xyz has no security.txt; fluxapay.xyz's is unchecked (0 of 20). Total 52.