Setting the redirect URL
The role of the single redirect URI on a developer app, the exact-match rule, separating environments, changing it, and common errors.
Creating a new app
How to register a developer app in a business account: the fields, how the credentials are shown, what you can do afterwards, and common stumbling points.
What is application registration
Explains the concept of ReceiptRoller application registration. Registering an app as an OAuth client issues a client ID, secret, and redirect URI, letting you start API and Webhook integrations.
Cannot obtain a token (authentication error)
How to narrow down a 400 or 401 from the token endpoint, with the fix for each error and error_description, including invalid_client and invalid_grant.
API Authentication Guide
How to authenticate with the OAuth 2.0 authorization code flow: authorize parameters, the consent screen, token exchange and revocation, errors and scopes.
Your first API call: from app registration to listing transactions
Get a token with the OAuth authorization code flow and PKCE, confirm the business account, list its transactions, and refresh the token.
Managing the client ID and client secret
Where to find the client ID and client secret, how to store them, regenerating the secret after a suspected leak, and running several environments.
Wallet App: Guide to Fetching a User's Receipts via OAuth
Explains how to fetch a user's Receipt Roller purchase receipts, with their consent, from a wallet-style app such as iOS, Android, or a LINE Mini App. Covers OAuth 2.0 authentication, the receipts API, and Webhook integration.
Connect an AI agent to ReceiptRoller over MCP
Connect Claude as an MCP connector, then build your own MCP client with dynamic client registration, PKCE and JSON-RPC calls over HTTP.