> ## Documentation Index > Fetch the complete documentation index at: https://agents.laso.finance/llms.txt > Use this file to discover all available pages before exploring further. # Upload a proof-of-address document > Attaches a proof-of-address document to the banking application, for the cases where the partner asks for one. The application must already exist and have an individual on it, so complete the application first. **Two things reject uploads that otherwise look fine.** A `.jpg` file must be sent as `fileType: "jpeg"` — `"jpg"` is refused. And the partner caps the *decoded* size at 10MB, even though their own upload page advertises 20MB; oversized files are rejected here before the round-trip. `fileContent` accepts either a bare base64 string or a `data:` URL, so a browser `FileReader.readAsDataURL` result can be passed through unchanged. This is a Firebase callable served from the Cloud Function URL (`https://us-central1-kyc-ts.cloudfunctions.net/uploadBankingDocument`), not the `https://laso.finance` base URL used by the paywalled routes. Callables wrap the request in `{"data": ...}` and the reply in `{"result": ...}`. Send the `id_token` from `/auth` as a Bearer token. Free. ## OpenAPI ````yaml /api-reference/openapi.json post /uploadBankingDocument openapi: 3.1.0 info: title: Laso Finance x402 API version: 1.0.0 x-docs-revision: 106571cd77c5 x-docs-manifest: https://laso.finance/.well-known/docs-version.json 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. 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. ## 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). All cards are intended for the caller's own use. For step-by-step instructions, read https://laso.finance/SKILL.md servers: - url: https://laso.finance description: Production security: [] paths: /uploadBankingDocument: post: tags: - Banking summary: Upload a proof-of-address document description: >- Attaches a proof-of-address document to the banking application, for the cases where the partner asks for one. The application must already exist and have an individual on it, so complete the application first. **Two things reject uploads that otherwise look fine.** A `.jpg` file must be sent as `fileType: "jpeg"` — `"jpg"` is refused. And the partner caps the *decoded* size at 10MB, even though their own upload page advertises 20MB; oversized files are rejected here before the round-trip. `fileContent` accepts either a bare base64 string or a `data:` URL, so a browser `FileReader.readAsDataURL` result can be passed through unchanged. This is a Firebase callable served from the Cloud Function URL (`https://us-central1-kyc-ts.cloudfunctions.net/uploadBankingDocument`), not the `https://laso.finance` base URL used by the paywalled routes. Callables wrap the request in `{"data": ...}` and the reply in `{"result": ...}`. Send the `id_token` from `/auth` as a Bearer token. Free. operationId: uploadBankingDocument requestBody: required: true content: application/json: schema: type: object required: - data properties: data: type: object required: - userId - documentType - fileType - fileContent - country properties: userId: type: string description: The Laso user id (the `usr_...` value from /auth). example: usr_7aff81763cae58c936aa6de67dd5a95e documentType: type: string enum: - proof_of_address - bank_statement - utility_bill description: The kind of document. example: utility_bill fileType: type: string enum: - pdf - jpeg - png description: The file's format. Send a .jpg as `jpeg`. example: jpeg fileContent: type: string description: >- The file, base64-encoded. A `data:` URL is also accepted. Decoded size must be 10MB or less. country: type: string description: The document's country, ISO 3166-1 alpha-2. example: US filename: type: string description: The file's name. example: utility-bill.pdf responses: '200': description: The created document id and its review status. content: application/json: schema: type: object properties: result: type: object properties: documentId: type: string status: type: string '400': description: A required field is missing or invalid. '401': description: Missing, invalid, or expired Bearer token. '403': description: The caller is not this user and is not an admin. '412': description: >- The application has no individual to attach a document to yet. Complete the application first. security: - BearerAuth: [] servers: - url: https://us-central1-kyc-ts.cloudfunctions.net components: 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). ````