Raise the rate limit

A 24-hour grant that lifts /quote from 60 to 600 requests per minute, paid over x402 or unlocked by a Pro Pass.

GET/api/sdk/v1/access

PAYMENT-SIGNATUREheader

addressquery

issuedquery

signaturequery

curl "https://www.swaps.pro/api/sdk/v1/access"

not rate limitednever cachedno API keyCORS open

Quotes are free and stay free. What this sells is capacity: the per-IP ceiling exists because every quote fans out to upstream venues whose quota SwapsPro does not own.

Two ways in. x402: call with no headers, receive a 402 challenge, pay the USDC amount it names on Base, call again with the PAYMENT-SIGNATURE header, receive the grant. Pro Pass: ?address=0x… returns a message to sign; send address, issued and signature back and the pass is read from chain, never asserted by the caller.

The grant is a bearer token. Everyone presenting it draws from the same bucket, so sharing it divides your headroom rather than multiplying it.

Parameters#

Name	In	Type	Description
`PAYMENT-SIGNATURE`	header	`x402 v2 payload`	The signed payment answering the 402 challenge. `X-PAYMENT` is accepted for x402 v1.
`address`	query	`address`	Pro Pass flow, step 1: the wallet holding the pass. Returns the message to sign.
`issued`	query	`ISO time`	Pro Pass flow, step 2: the `issued` value from step 1, verbatim.
`signature`	query	`0x signature`	Pro Pass flow, step 2: EIP-191 personal_sign of the step-1 message.

Responses#

Success is the body below. Every error is { "error": string, "code": string } with a matching HTTP status — never a 200 that says no.

When: payment settled, or the Pro Pass signature verified. Shape from the route source; the token and subject are placeholders.

{
  "token": "sp_acc_…",
  "header": "X-SwapsPro-Access",
  "subject": "0x21c9…Ad3e",
  "via": "x402",
  "limit": {
    "requestsPerMinute": 600,
    "previously": 60
  },
  "expiresAt": "2026-09-04T12:00:00.000Z",
  "ttlSeconds": 86400,
  "usage": "Send \"X-SwapsPro-Access: <token>\" (or \"Authorization: Bearer <token>\") on GET /api/sdk/v1/quote.",
  "note": "Quotes are free at 60 requests per minute with no credential at all — this token only raises the ceiling. It is a bearer token: everyone presenting it draws from the same bucket, so sharing it divides your headroom rather than multiplying it."
}

Fields worth knowing#

Field	Meaning
`token`	the bearer grant
`header`	the header name to send it as
`limit.requestsPerMinute`	the new ceiling; `previously` is the free one
`expiresAt / ttlSeconds`	when the grant stops working

For agents#

The brief below is what Copy for agents puts on the clipboard: the parameters, one example, the 200 body and the rules. It is Markdown, and it is short on purpose — everything in it is load-bearing.

Do not buy a grant until you have actually been rate limited (a 429 from /quote). At the free ceiling most agents never need one.
Keep the token server-side. Presenting it from many clients shares one bucket.
The route may answer 503 with missingConfig on a deployment without a facilitator; treat that as "no grants here", not as a retryable error.

← GET /quote