> ## Documentation Index > Fetch the complete documentation index at: https://docs.laso.finance/llms.txt > Use this file to discover all available pages before exploring further. # Unlink the card issuer > Removes the link between this Laso account and the card issuer, the same as the disconnect button in the dashboard. The card and its balance stay with the card issuer untouched; only Laso's link is removed. **What stops working.** Every reloadable card route and saved card purchases (`POST /buy-with-saved-card`) need the link, so they fail until the account holder links again with `POST /start-card-issuer-link` and a fresh code that only they can receive. Confirm with the account holder before calling this. Safe to repeat: an account with no link answers the same way. Afterwards `GET /get-card-issuer-status` reads `not_started`. **This route is free.** Requires a Bearer token from `/auth` or `/get-card`. ## OpenAPI ````yaml /api-reference/openapi.json post /disconnect-card-issuer openapi: 3.1.0 info: title: Laso Finance x402 API version: 1.0.0 x-docs-revision: 2c96f69d4fc3 x-docs-manifest: https://laso.finance/.well-known/docs-version.json termsOfService: https://laso.finance/agent-terms.md contact: email: agents+support@laso.finance x-guidance: >- Laso Finance is a payment-gated (x402) API that lets an AI agent spend USDC on real-world financial products: prepaid cards (U.S. and international), gift cards, push-to-card transfers to USD/EUR/GBP debit cards, and Venmo/PayPal payouts. Payment: every paid route is an x402 v2 endpoint. Call it with no payment header to receive a 402 challenge listing the accepted networks, then replay with a signed USDC payment. Both Base (eip155:8453) and Solana (solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp) are accepted on every paid route; the caller picks either chain. Identity: `GET /auth` is free and identity-only. Prove wallet ownership with a `SIGN-IN-WITH-X` (CAIP-122) header to receive a Firebase id_token, then send that token as a Bearer credential to the authenticated read routes (`get-card-data`, `get-account-balance`, `get-kyc-status`, etc.). Paid routes also return fresh auth credentials in their response, so a payment is never required just to obtain a token. Recommended flow: (1) `GET /auth` to establish identity, (2) call a paid route (e.g. `GET /get-card`) to purchase a product, paying USDC on Base or Solana, (3) poll the authenticated read routes with the returned Bearer token to fetch the resulting card/transfer details. Reloadable card setup: the account holder links the card issuer once. Check `GET /get-card-issuer-status`; if it is `not_started`, call `POST /start-card-issuer-link` so the card issuer sends the account holder a one-time code, have the HUMAN read it from their own inbox and enter it in your interface (never read their email yourself), then `POST /verify-card-issuer-link` with the code and `consent_accepted: true`. Linking requires Laso identity verification (`kyc_required` returns a `kyc_url` for the human). Then fund with `GET /fund-card-balance` and create cards with `POST /create-reloadable-card`. Full machine-readable instructions live at https://laso.finance/SKILL.md. description: >- Payment-gated API for Laso Finance. All paywalled routes use the x402 protocol — the caller includes a USDC payment header on Base (eip155:8453) or Solana (solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp) and the server verifies payment before processing. Free routes require no payment header. The same 402 also carries an MPP (Machine Payments Protocol) challenge in WWW-Authenticate; an MPP client pays with USDC on Base by replaying with `Authorization: Payment ...`, and routes, prices, and responses are identical. ## Getting started To set up a wallet for making x402 payments, choose a provider: - **Locus** (default): https://paywithlocus.com/SKILL.md - **Sponge**: https://wallet.paysponge.com/skill.md — automatic x402 service discovery - **Ampersend**: https://www.ampersend.ai/getting-started.md — self-custody on Base or Solana with dual-approval spending limits. Laso Finance is a default skill, so no manual endpoint registration is needed. ## How x402 works 1. Call a paywalled endpoint without a payment header → receive a `402 Payment Required` response containing payment details (price, recipient address, network). 2. Construct an x402 payment header using the details from the 402 response. 3. Replay the request with the payment header → the server verifies payment and processes the request. ## Authentication flow `GET /auth` is free: callers prove wallet ownership by sending a `SIGN-IN-WITH-X` header (CAIP-122 wallet signature). Paywalled routes (`/get-card`, `/order-gift-card`, `/get-push-to-card`, `/order-intl-card`) also return fresh auth credentials in their responses, so a payment is never required just to obtain a token. Most routes return auth credentials (`id_token`, `refresh_token`, `expires_in`). Use the `id_token` as a Bearer token to call authenticated Laso Finance endpoints like `/get-card-data`. When the `id_token` expires, use `POST /auth` with `grant_type: refresh_token` to get a new one. ## Important notes The `/get-card` USA prepaid card endpoint is U.S. only — issued in USD, usable at U.S.-based merchants only, and physical goods must ship to a U.S. address. For non-U.S. merchants or non-USD currencies, use `GET /order-intl-card` instead (international prepaid card, admin-fulfilled within 24 hours). Agents act for a principal (a person 18+ or a business entity) under the [Agent Terms](https://laso.finance/agent-terms.md): every action is treated as the principal's own, and cards may be used for the principal's personal or business purchases. ## Rate limits Every response carries the request budget so you can pace yourself without probing for a limit: | Header | Meaning | | --- | --- | | `RateLimit-Limit` | Requests permitted per window | | `RateLimit-Remaining` | Requests still available | | `RateLimit-Reset` | Seconds until the window rolls over | | `RateLimit-Policy` | The policy these numbers describe, as `limit;w=seconds` | The same values are repeated as `X-RateLimit-*` for clients that only parse that spelling. Most routes advertise the service-wide ceiling. `POST /signup` enforces its own per-IP budget on top of it and overwrites these headers with its own numbers. `POST /refresh-card-data` is limited per card rather than per caller, so its headers keep the service-wide values and the per-card budget is reported only on rejection. Every rejection is a `429` carrying `Retry-After` in seconds and a matching `retry_after_seconds` field in the body, computed from the limit that actually rejected the request. Wait that long and retry once. Do not retry in a tight loop. ## API versioning Every response carries the contract version in an `X-Laso-Api-Version` header, and `GET /version` returns the same value as `api_version` alongside the policy below in machine-readable form. It is distinct from `X-Laso-Docs-Version`, which tracks the prose and moves whenever the documentation changes. | Change | What happens to `api_version` | | --- | --- | | New route, new optional request field, new response field | Unchanged. Tolerate unknown response fields. | | Breaking change | Ships under a new `api_version`. | A route being retired is marked `deprecated` in this description and answers with a `Deprecation: true` response header, plus a `Link` header with `rel="successor-version"` pointing at its replacement. Once a removal date is set it is published in a `Sunset` header (RFC 9745 / RFC 8594). There is no blanket notice period: the `Sunset` date on each deprecated route is the commitment. For step-by-step instructions, read https://laso.finance/SKILL.md servers: - url: https://laso.finance description: Production security: [] paths: /disconnect-card-issuer: post: tags: - cards summary: Unlink the card issuer description: >- Removes the link between this Laso account and the card issuer, the same as the disconnect button in the dashboard. The card and its balance stay with the card issuer untouched; only Laso's link is removed. **What stops working.** Every reloadable card route and saved card purchases (`POST /buy-with-saved-card`) need the link, so they fail until the account holder links again with `POST /start-card-issuer-link` and a fresh code that only they can receive. Confirm with the account holder before calling this. Safe to repeat: an account with no link answers the same way. Afterwards `GET /get-card-issuer-status` reads `not_started`. **This route is free.** Requires a Bearer token from `/auth` or `/get-card`. operationId: disconnectCardIssuer parameters: - $ref: '#/components/parameters/IdempotencyKey' responses: '200': description: Unlinked. content: application/json: schema: type: object required: - status - note properties: status: type: string enum: - not_started description: >- The link state after unlinking, as `GET /get-card-issuer-status` reports it. note: type: string description: How to link again. example: status: not_started note: >- The card issuer is unlinked from this account. The card balance stays with the card issuer. To use reloadable or saved cards again, link it with POST /start-card-issuer-link and the code the account holder receives. headers: Idempotency-Replayed: $ref: '#/components/headers/Idempotency-Replayed' X-Laso-Api-Version: $ref: '#/components/headers/X-Laso-Api-Version' '401': description: Missing or invalid Bearer token content: application/json: schema: $ref: '#/components/schemas/Error' example: error: Missing or invalid Authorization header headers: X-Laso-Api-Version: $ref: '#/components/headers/X-Laso-Api-Version' '403': description: >- Account is frozen. The response includes a `frozen_message` field explaining why. content: application/json: schema: $ref: '#/components/schemas/FrozenError' example: error: Account is frozen frozen_message: >- Your account is frozen pending a compliance review. Contact support@laso.finance. headers: X-Laso-Api-Version: $ref: '#/components/headers/X-Laso-Api-Version' '409': description: >- A request with this `Idempotency-Key` is still being processed (`code: idempotency_key_in_progress`). Wait a moment and retry with the same key. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: A request with this Idempotency-Key is still being processed code: idempotency_key_in_progress headers: X-Laso-Api-Version: $ref: '#/components/headers/X-Laso-Api-Version' '422': description: >- The `Idempotency-Key` was already used for a different request body or route (`code: idempotency_key_reused`). Use a new key. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: Idempotency-Key reused with a different request code: idempotency_key_reused headers: X-Laso-Api-Version: $ref: '#/components/headers/X-Laso-Api-Version' security: - BearerAuth: [] components: parameters: IdempotencyKey: name: Idempotency-Key in: header required: false schema: type: string maxLength: 255 description: >- Optional client-generated unique key (a UUID works) that makes this write safe to retry. A retry with the same key within 24 hours returns the recorded response of the original request, marked with an `Idempotency-Replayed: true` header, instead of performing the write again. Reusing a key with a different body or route is rejected with 422 (`code: idempotency_key_reused`); a retry that arrives while the original is still running gets 409 (`code: idempotency_key_in_progress`), so wait a moment and retry with the same key. Keys are scoped to the authenticated account. headers: Idempotency-Replayed: description: >- Present, with the value `true`, when this response was replayed from an earlier request that carried the same `Idempotency-Key` rather than executed again. schema: type: string enum: - 'true' X-Laso-Api-Version: description: >- The version of the API contract that produced this response, the same value `GET /version` returns as `api_version`. It moves only on a breaking change, so an agent can pin against it and tolerate unknown response fields without rechecking the docs. Distinct from `X-Laso-Docs-Version`, which tracks the prose. Present on every response once the service has read its version beacon; absent, rather than a placeholder, during the cold-start window before that read completes. schema: type: string example: 1.0.0 schemas: Error: type: object properties: error: type: string FrozenError: type: object properties: error: type: string example: Account is frozen frozen_message: type: string description: Human-readable explanation of why the account is frozen securitySchemes: BearerAuth: type: apiKey in: header name: Authorization description: >- Firebase ID token from `/auth` or any paid route, sent as a Bearer token: `Authorization: Bearer ` (the `Bearer ` prefix is required). ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.