For AI agents
Give your agent a phone number.The phone layer for software that acts on its own.
More and more businesses let an agent handle their texting: appointment reminders, order updates, answers to customers who text in. TextKit turns that into API calls an agent can make, from the business's own registered number, with the same consent, opt-out and content checks as every other message.
A registered business number
Provision a number for your business in one call; your agent texts from it and reads the replies. $0.95 a month. We verify your business and file the carrier registration for you (registry fees are billed separately). Until the carriers approve it, the number can text only your own verified numbers.
POST /v1/numbers { "phone_number": "+14155550132" }
An SMS inbox it can act on
Inbound texts land as clean JSON events. An agent can poll /v1/events or take a webhook, read the message, and decide what to do next: confirmations, replies, hand-offs.
GET /v1/events?type=message.received
Phone verification as a primitive
When your product needs to confirm a user's phone number, the OTP flow is two calls. TextKit generates and delivers the code, enforces expiry and attempts, and blocks SMS pumping. Billed only on success.
POST /v1/verify, then POST /v1/verify/check
Know what kind of number it is
Before an agent trusts a number, one lookup returns line type and carrier, so it can tell a mobile from a landline or a VoIP number before it sends.
GET /v1/lookup/+14155550132
Built for agents and the people who run them
Every surface has a machine-readable form: an MCP server for tool calls, skills that encode the integration rules, markdown twins of every docs page, and a sandbox where test keys simulate the whole carrier so agents can iterate for free.
MCP https://mcp.jointextkit.com
Skills curl -sSL https://jointextkit.com/skills/install.sh | sh
Docs https://jointextkit.com/docs/llms-full.txt
Spec https://api.jointextkit.com/v1/openapi.yaml