Frequently asked questions
Short answers about identity, keys, payment, receipts, caching, limits, refunds, sanctions, counts, moderation and Integrator. Each answer links to the page that holds the full fact.
Do I have to sign up?
No. Point an MCP client at https://apibase.pro/mcp. Your first payment, on x402 or MPP, creates your agent identity from the wallet. There is no dashboard signup, no email and no approval queue. Steps: /connect.
How do I get an API key?
Send one unauthenticated POST https://apibase.pro/api/v1/agents/auto. The reply holds an agent_id and an api_key starting ak_live_, on the free tier. Use it as Authorization: Bearer. Registration details: /auth.md.
Which payment rails are accepted?
x402 (USDC on Base) and MPP (USDC.e on Tempo). Use one per request. How they differ: x402 vs MPP.
What does a call cost?
Every tool has a fixed published price: $0.0005–$29.99 per call (p90 $0.003). There is no plan, no included quota and no overage fee. Free tools cost $0. Tiers and per-tool prices: /pricing.
How do I know what I was charged?
Each billed x402 or MPP call returns an X-APIbase-Receipt header with a public, immutable receipt at https://apibase.pro/r/<receipt_id>.json. What a receipt holds is in the privacy policy.
Is a repeated call cached or charged twice?
A tool response is cached for its own TTL. On x402 an identical repeated lookup by the same wallet within 2 minutes is answered from cache and not charged; the response carries X-APIbase-Charged: false. On MPP a cache hit is billed in full. Details: /pricing.
What are the rate limits?
The free tier allows 10 requests per second and 100 per day. Paid and enterprise tiers are higher. All three are on /connect.
What happens when the provider fails?
On x402 a failed provider call is not settled, so nothing leaves your wallet. On MPP a refund is owed and paid out by the operator. Details: /pricing#refunds.
Are payments screened for sanctions?
Yes. Paying wallets are screened before each settlement; a match is refused and the attempt is not charged. The countries and rules are in the Terms, section 12a.
Where do the tool and provider counts come from?
They are generated from the live catalog and published in /llms.txt and /.well-known/site-facts.json. The catalog at /api/v1/tools lists every tool with its status. This site does not repeat the numbers in prose.
Is my content moderated?
Calls to action tools, which send a message, place a call or post content, are scanned against a fixed ruleset before they reach the provider. Every other tool is checked only against the child-safety rule. A blocked paid call is still charged and can be appealed within 14 days. Policy: /policy/moderation.
What is Integrator?
Integrator is AI payment for merchants: an MCP storefront for a shop, paid by AI agents straight to the merchant wallet. The fee and limits are stated once, on /pricing; the product is on /integrator.