For AI agents: a documentation index is available at the root level at /llms.txt and /llms-full.txt. Append /llms.txt to any URL for a page-level index, or .md for the markdown version of any page.
Contact SalesGet Support
HomeGuidesAPI reference
HomeGuidesAPI reference
  • Get started
    • Quickstart—Verify a Business
    • Quickstart—Register an entity for payroll taxes
    • Learn how Middesk works
    • Security
    • Changelog
  • Build with Middesk
    • Get your API keys
    • Understand API changes
    • Status codes and errors reference
    • Implement webhooks
    • Secure webhooks
    • Use GraphQL
    • Connect MCP
  • Verify a business (KYB)
    • Verify TIN
    • Verify name and address
    • Verify Secretary of State status
    • Verify owners and officers
    • Screen for sanctions and watchlists
    • Search for adverse media
    • Search for Politically Exposed Persons
    • Implement KYC
    • Discover connections
    • Evaluate online presence
    • Assess credit risk
    • Accelerate onboarding
    • Monitor business activity
    • Manage business entities
    • Work with agents
LogoLogo
Contact SalesGet Support

Build with Middesk

Learn how to build an integration using the Middesk REST API.
Built with
Get and use your API keys

Find your Middesk API keys and see how to use them.

Status codes and error messages

Read about the HTTP status codes and error response formats used by the Middesk API.

Implement webhooks

Use webhooks to receive real-time notifications of key account activity.

Secure webhooks

Authenticate webhook requests using HMAC signatures, mutual TLS, or OAuth.

Use GraphQL

Query Middesk business data through the optional GraphQL API.

Understand API changes

Learn how Middesk versions the API and handles backwards compatibility.

Get a demo
Contact your account manager or contact sales to inquire about access.