Cards & credentials

Your users connect their cards to the Agentcard Wallet. When their agent needs to pay, Agentcard provides a card from the wallet for that one payment. Linq hands your agent a short handoff — not the raw card — and the agent reads the card directly from Agentcard.

• The agent gets a card from the user’s wallet, scoped to that payment and used once.
• The card is scoped to the payment’s amount_cents, currency, and merchant.
• There’s nothing for you to store, rotate, or clean up — each payment gets its own.

When a payment is ready, fetch the handoff from Linq:

curl https://api.linqapp.com/api/partner/v3/payments/{paymentId}/credentials \
  -H "Authorization: Bearer $LINQ_API_KEY"

{
  "handoff": {
    "provider": "agentcard",
    "user_token": "<short-lived bearer>",
    "card_ref": "card_7h2k",
    "fetch_url": "https://api.agentcard.sh/api/v2/cards/card_7h2k"
  }
}

Your agent calls fetch_url with the user_token to read the card, then enters it at the merchant:

curl "$FETCH_URL" -H "Authorization: Bearer $USER_TOKEN"

• Never through Linq. The card number is fetched directly from Agentcard; it does not pass through Linq’s servers.
• Short-lived. The user_token expires quickly — fetch the card right before the agent pays, not ahead of time.
• Do not persist PAN/CVC. Use the card details in memory and discard them.

The customer can review the card and every transaction in their wallet — you don’t build any of this UI.

If the charge is declined, the payment goes to declined — create a new payment (and fetch a new handoff) to retry. Don’t reuse a spent handoff.

• Create & complete a payment
• Webhooks & lifecycle