Cost, custody, caps, and the treasury model behind runtime agent payments — in short answers.

What does SELAT actually do?

SELAT is skill settlement: it pays every paid endpoint that a skill calls — across x402, MPP, or whatever ships next — from one self-custody treasury, in one execution. Every call is mapped 1:1 to the named merchant it paid, visible in your history — nothing pooled, nothing redistributed.

What does it cost?

You pay each merchant's live quote per call — the merchant prices the request the moment your agent probes the endpoint, and you see it before you run. Simple calls — search, scraping, enrichment — run $0.001–$0.05; heavier endpoints like media generation or deep research run tens of cents to a few dollars.

SELAT's fee: 0% on endpoints from the Circle Agent Marketplace (agents.circle.com), 5% on endpoints from other registries (Agentic.Market, MPP services, Apify) — included in the quote you see.

How is this different from an API key?

An API key is something you sign up for, store, and can leak. A settled call is a payment your agent makes at the moment it's needed — mapped to the merchant it paid, no stored secrets.

Is this crypto? Do I need to buy tokens?

Your agent's treasury holds USDC — that's it. No native ETH, no gas to hold, no exchange account. Fund once via Circle Gateway and every paid call draws from that balance.

Who holds my funds?

You do. You hold the treasury through a non-custodial agent wallet — Circle Agent Wallet by default today. It's MPC: the private key never exists as a file anywhere, on your machine or ours. SELAT never holds your keys and never custodies your balance — your USDC stays yours until you sign a per-call payment; SELAT's settlement wallet is a transient hop, not a stored float. Skills are declarative: a skill can ask for a payment, but only your wallet can sign one, and your caps are checked before it does. A skill can ask; it can't sign.

What stops a bad skill from draining my treasury?

Hard caps — per-transaction, daily, weekly, monthly limits you set, enforced in the settlement path, not in the skill's prose. A compromised skill can request settlement, but can't exceed your caps or reach your keys.

How do I see what my agent spent?

One ledger. Every settled call — every skill, every rail — lands in a single reconciled view: selat history.

Do I need a wallet for every chain or every rail?

No — one balance, on one chain. Fund USDC on any one of the 11 EVM chains Circle Gateway supports, and that single deposit settles merchants wherever they are. A chain is where your treasury lives; a rail is how a merchant gets paid (x402 or MPP). One treasury; every rail draws from it.

Which agent harnesses does this work with?

Any harness that reads install.md — Claude Code, Codex, Cursor, OpenClaw, Hermes, and more.

Do I need to store API keys to compose a skill?

No — none in the source, and none demanded at runtime. Payment is the auth: each endpoint is paid at the moment it's called — no signups, no secrets to provision, nothing redistributed. Some merchants issue a prepaid access token at runtime; that's a receipt, not a key — proof of a payment already made, bounded by its remaining balance, governed by your caps.

Does this replace OAuth integrations like Gmail or Slack?

No. SELAT's catalog covers commercial paid endpoints — it doesn't replace OAuth access to your own SaaS accounts.

How is this different from an API aggregator or proxy?

Aggregators and proxies remove key sprawl by pooling accounts for you — and they gatekeep the catalog: your agent reaches only the merchants they've chosen to integrate. SELAT removes accounts entirely and federates the catalog: any merchant that publishes an endpoint behind an HTTP 402 payment protocol is already reachable. Payment is the access. Protocol is the integration.