> ## Documentation Index > Fetch the complete documentation index at: https://docs.suby.fi/llms.txt > Use this file to discover all available pages before exploring further. # Chains and tokens this account accepts > Scoped to the caller, not the global catalogue. A headless integration built off the full catalogue offers assets the merchant never enabled, and the payer only finds out when the charge is refused. Tokens come nested under their chain. A chain's name, icon and payable `modes` are facts about the CHAIN, so they are stated once per chain rather than repeated on every token · the payload grows with the number of chains, not with the catalogue. `modes` says how a chain's tokens can actually be paid. Bitcoin is deposit-only · it has no contracts to sign against · so a UI that renders a "connect wallet" button on it builds a flow the API refuses. SANDBOX returns testnet chains, LIVE mainnet: a sandbox integration is never handed a mainnet address to send real funds to. ## OpenAPI ````yaml /v3-beta/api-reference/openapi.yaml get /v3/crypto/assets openapi: 3.1.0 info: title: Suby.fi Merchant API version: 3.0.0-beta description: > The **v3** public merchant API for Suby.fi. RESTful (plural, resource-oriented endpoints under the `/v3` prefix). Authenticate every request with your secret API key in the `X-Suby-Api-Key` header. - `sk_live_…` keys operate in **production** (real funds). - `sk_sandbox_…` keys operate in a fully simulated **sandbox** (test cards, Base Sepolia crypto, no real money). The environment is derived from the key prefix. contact: email: contact@suby.fi url: https://suby.fi servers: - url: https://api.beta.suby.fi description: Production + sandbox (environment selected by API key prefix) security: - ApiKeyAuth: [] tags: - name: Products description: Manage your product catalog (one-time and recurring). - name: Checkout description: >- Hosted checkout · signed session tokens (`cs_…`). Every card Suby holds was collected here, which is what keeps card data out of your systems. - name: Payments description: >- Read payments and receipts, refund them, and debit a stored instrument off-session (pay-as-you-go). Collecting a card happens on the hosted checkout, never here. - name: Subscriptions description: >- Drive a live subscription · read it, change its plan, end it. Subscriptions are opened by a checkout session, not by this API. - name: Discount Codes description: Promo codes, redeemed at checkout. - name: Crypto description: >- The headless rail · quote, charge, and settle on-chain from inside your own site. No card data is involved, so none of the constraints that keep card collection on a Suby page apply here. - name: Customers description: First-class customer records with billing address. - name: Payment Methods description: >- Read and detach the cards a customer has stored. They are created by a checkout session (`savePaymentMethod`, or `mode=setup`) · the only place a card is collected. - name: Licence Key description: >- The licence server · validate a key, take a seat, free one. Authenticated with your API key like everything else, and scoped to the licences you issued, so your backend relays the check rather than your customer's software calling it directly. paths: /v3/crypto/assets: get: tags: - Crypto summary: Chains and tokens this account accepts description: > Scoped to the caller, not the global catalogue. A headless integration built off the full catalogue offers assets the merchant never enabled, and the payer only finds out when the charge is refused. Tokens come nested under their chain. A chain's name, icon and payable `modes` are facts about the CHAIN, so they are stated once per chain rather than repeated on every token · the payload grows with the number of chains, not with the catalogue. `modes` says how a chain's tokens can actually be paid. Bitcoin is deposit-only · it has no contracts to sign against · so a UI that renders a "connect wallet" button on it builds a flow the API refuses. SANDBOX returns testnet chains, LIVE mainnet: a sandbox integration is never handed a mainnet address to send real funds to. operationId: listCryptoAssets parameters: - name: chainId in: query description: Restrict to one chain. Omit for everything the account accepts. schema: type: integer example: 8453 responses: '200': description: Accepted assets content: application/json: schema: allOf: - $ref: '#/components/schemas/SuccessEnvelope' - properties: data: type: object properties: chains: type: array items: $ref: '#/components/schemas/CryptoChainAssets' '401': $ref: '#/components/responses/Unauthorized' components: schemas: SuccessEnvelope: type: object required: - success - data properties: success: type: boolean example: true message: type: string data: description: Endpoint-specific payload. CryptoChainAssets: type: object description: One chain and the tokens of it this account accepts. Never empty. properties: chainId: type: integer example: 8453 description: The on-chain id · what you send back as `chainId`. name: type: string example: Base isEvm: type: boolean description: EVM chains share one wallet adapter; Solana and Bitcoin do not. logoUrl: type: string nullable: true modes: type: array description: >- How THIS CHAIN's tokens can be paid. Bitcoin is `qr_deposit` only · no contracts to sign against. items: type: string enum: - qr_deposit - wallet_connect assets: type: array description: Stables first, then alphabetical. items: $ref: '#/components/schemas/CryptoAsset' CryptoAsset: type: object properties: asset: type: string example: USDC description: >- The ticker, and the public key for this token alongside the chain's `chainId`. Pass it back as `asset` on a quote or a charge. name: type: string example: USD Coin decimals: type: integer example: 6 isStable: type: boolean isNative: type: boolean description: The chain's gas token (ETH on Base, SOL on Solana). logoUrl: type: string nullable: true Error: type: object required: - success - error properties: success: type: boolean example: false error: type: string description: Machine-readable error code. example: NOT_FOUND message: type: string example: Resource not found data: description: Optional error detail. responses: Unauthorized: description: Invalid or missing API key content: application/json: schema: $ref: '#/components/schemas/Error' example: success: false error: UNAUTHORIZED message: Invalid or missing API key securitySchemes: ApiKeyAuth: type: apiKey in: header name: X-Suby-Api-Key description: Secret API key. `sk_live_…` (production) or `sk_sandbox_…` (sandbox). ````