> ## Documentation Index
> Fetch the complete documentation index at: https://docs.anchorage.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Crypto payments

> How Anchorage Agentic Banking settles a paid URL on the crypto rail.

Anchorage Agentic Banking's crypto rail lets an agent pay any URL that
quotes a price. The protocol underneath is [**x402**](https://x402.org), an
HTTP-402 challenge/response that turns a URL into a paywall an agent can
satisfy.

From the agent's perspective it is a single call: supply a URL, an
idempotency key, and the budget to draw on; the platform does the rest.

## What Anchorage Agentic Banking does for you

The agent only supplies a URL. Anchorage Agentic Banking owns every merchant-side interaction:

<Steps>
  <Step title="Fetch">
    Anchorage Agentic Banking issues the agent's GET or POST to the merchant URL.
  </Step>

  <Step title="Read the 402">
    The merchant responds with HTTP 402 and an `accepts` array describing the
    price and acceptable rails.
  </Step>

  <Step title="Select">
    Anchorage Agentic Banking picks the cheapest payable entry among the
    chains the agent is set up to pay on. Today: USDC on Base (EVM) and USDC
    on Solana.
  </Step>

  <Step title="Gate">
    Compliance and spending gates run. Failures here return a structured
    error to the agent.
  </Step>

  <Step title="Sign">
    Anchorage Agentic Banking signs the payment authorization for the
    selected chain — an off-chain EIP-3009 authorization on Base, or an SPL
    token transfer on Solana. {/* req: payments/x402.md#2 */}
  </Step>

  <Step title="Retry">
    Anchorage Agentic Banking re-issues the request with the payment header. The merchant's
    facilitator broadcasts to chain; the merchant returns the resource.
  </Step>

  <Step title="Return">
    The merchant's response body lands in the agent's tool result.
  </Step>
</Steps>

## Approvals

When a crypto payment exceeds the budget cap (but passes compliance), the
payment is queued as `pending_approval`. The agent gets a structured
response naming the approval; an org admin sees the request in the
Anchorage Agentic Banking web UI under **Approvals** and approves or denies
it. {/* req: policies/approval-flows.md#2 */}

After an org admin approves, the agent polls for the verdict and then re-issues
the payment with the **same** idempotency key to resume.

Pending approvals expire after 24 hours and auto-deny. After that, the
agent mints a new request with a new idempotency key to try again.

Compliance failures (merchant not on allowlist, merchant inactive) are hard
rejects — they stay outside the approval queue.

## Idempotency

`idempotency_key` is **agent-scoped**: two calls from the same agent with the
same key collapse to one transaction; the same key from a different agent is a
separate transaction. Use a fresh key for every distinct intent.

## The agent's view

The agent sees the URL it asked for and the merchant response body it gets
back. Negotiation detail — the accepts array, the signed EIP-3009 payload,
the facilitator's address, the funding account's balance — is handled
inside Anchorage Agentic Banking and stays internal.

## Failure modes

| Verdict                      | What it means                                              | What to do                                                                                |
| ---------------------------- | ---------------------------------------------------------- | ----------------------------------------------------------------------------------------- |
| Compliance mismatch          | Merchant not on allowlist or inactive                      | Pick a different merchant                                                                 |
| Spending mismatch            | Over the budget cap                                        | Ask an org admin to approve, then poll for the approval verdict                           |
| Daily safety cap reached     | Hard reject, no approval path                              | See [Stopping a runaway agent](/agentic-banking/concepts/agents#stopping-a-runaway-agent) |
| Agent deactivated            | Hard reject, no approval path                              | See [Stopping a runaway agent](/agentic-banking/concepts/agents#stopping-a-runaway-agent) |
| Account locked or frozen     | Hard reject, no approval path                              | Contact Anchorage support — resolution requires staff action                              |
| Insufficient account balance | Hard reject, no approval path                              | Fund the account, then retry                                                              |
| Schema mismatch              | Request body doesn't match the merchant's published schema | Fix the request body and retry with a **new** idempotency key                             |
| Upstream 5xx                 | Merchant indeterminate                                     | Retry with the **same** idempotency key — repeat calls collapse to one settlement         |