Single Brain

Single Brain Gateway gives developers and operators a single API key that lets any AI agent reach into the SaaS accounts a business already runs. Connecting once exposes Google Analytics, Search Console, Slack, HubSpot, Stripe and around 50 other tools, so teams stop building and maintaining a separate integration for every agent they ship. Under the hood, every connector points at accounts the customer already owns, with delegated OAuth, tools scoped to what was connected, and one endpoint that speaks either MCP or plain HTTP. The launch matters because agent teams keep hitting the same wall, namely per-tool auth, token refresh, permission scoping, and per-tenant isolation. Single Brain handles OAuth, refresh and revocation, and enforces which tools an agent can see based on the accounts a given org actually connected, with access enforced at the database layer rather than relying on application code to remember to check. That turns a multi-week integration backlog into a connect-and-call step, which is the practical unlock for anyone trying to run more than a demo agent in production. The gateway sits alongside Single Brain's core offering, a managed fleet of revenue agents that live inside Slack and Microsoft Teams and cover sales, creative, SEO, analytics, and paid media work. It is built by Eric Siu, who also runs the digital marketing agency Single Grain and hosts the Marketing School and Leveling Up podcasts, so the product is shaped by an operator who has been running these workflows against real client revenue before packaging them for other teams.