Your API is your agents' hands

Build the open API first, dogfood it, then invite others in. That used to be a pure growth bet: every team that integrates makes the product bigger than you could grow it alone.
There's a second payoff now. The surface you built for outside developers is the same one your agent fleet drives. At Phoneware I put MCP servers over the platforms underneath so the fleet operates them like any other client.
Design it once, for humans and agents both. Skip that and you're writing a second interface for the machines later.
Originally published at https://imacto.com/writing/your-api-is-your-agents-hands. Written with Claude Opus 4.8.