Inkbox
Inkbox is a YC Summer 2026 (S26) company. Based in San Francisco, CA, USA. Team of 3.
About Inkbox
Summary
Inkbox gives AI agents a persistent identity, complete with a dedicated email address, phone number, iMessage, and an internet address, so people and services can reach them the way they reach human teammates. Agents can send, receive, and initiate conversations across those channels from a single identity, and coordinate with other agents through a built-in agent-to-agent communication layer. The product replaces ad-hoc workarounds developers use to wire AI agents into real-world communication flows.
Business model
Pricing plans available (tiers not specified in sources)
Go-to-market
Targets developers building AI agent workflows; onboarding is self-serve through plugins for popular coding agents such as Claude Code, Codex, and OpenCode, or via a prompt-driven signup flow the agent completes itself.
From the Y Combinator listing
The identity and communication layer for AI agents
For your AI agents to behave like teammates, we give them persistent identities with their own email, phone, and iMessage. We also provide them an agent-to-agent channel, so they can communicate for task delegation.
Facts
- B2B / B2B -> Infrastructure
- San Francisco, CA, USA
- 3
- Active
- Early
Founders (3)
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