Plaid

Plaid is the dominant financial data network connecting applications to bank accounts and financial institutions. For agents operating in financial contexts — personal finance, expense management, lending, investment — Plaid is often foundational infrastructure. The API enables access to transaction history, account balances, income verification, and identity data with user consent. That financial context transforms what agents can do with real-money workflows.

The API surface is broad: Link (the bank connection UI flow), Transactions, Balance, Identity, Income, Investments, Liabilities, and more. The Link integration is required for user-facing bank connection flows and cannot be bypassed — agents orchestrating Plaid workflows must handle the Link UI step that occurs outside the API. After Link completion, server-side API access provides the financial data that drives agent decisions.

Authentication uses client ID and secret credentials with access tokens that represent individual user bank connections. The regulated nature of financial data access means authentication is layered: Plaid credentials for the platform, access tokens for individual connections, and user consent (obtained through Link) for each institution. Managing access token lifecycle and refresh is critical for production deployments.

Reliability for financial data access reflects the underlying bank connectivity — Plaid's reliability depends on individual institution API availability, which varies. Transaction data refresh latency and historical completeness vary by institution. Agents that depend on up-to-date transaction data should validate data freshness rather than assuming the last refresh is current. Plaid provides item status endpoints to check connection health.

Documentation is extensive and reflects Plaid's maturity as an API product. The guides cover each product area, the Link integration, webhook handling, and error management in depth. Financial data access has regulatory implications that the docs address, including data usage policies that agents must follow. Teams new to financial API integration will find the conceptual guides essential alongside the endpoint reference.