# CAI.com — a custodial @cai.com email, multi-chain stablecoin wallet, and MCP-installable agent API > Source: > Published: 2026-07-04 15:42:03+00:00 A custodial email, a stablecoin wallet, a credential vault, and an agent-ready API — all at one `@cai.com` address. This post walks through what CAI is, what you get when you sign up, and how to wire the agent side into any MCP-compatible host. A free `@cai.com` email comes with four product surfaces, all under one account: `@cai.com` .`cai.com/capabilities.html` ).`pay` and `full` scopes may require verification. The key is in the account dashboard.The signup at `cai.com/app` is four steps. About 2 minutes. `cai.com/app` . Pick "Apply for `@cai.com` email."At the end you have: `@cai.com` email address.No card. The email is free. For the technical reader, the agent side is the reason to look at CAI. The install is one command: ``` npm i -g @cailab/mcp ``` The package is the MCP server — a thin wrapper around the CAI HTTPS Edge API at `https://api.cai.com/functions/v1` . It drops into MCP-compatible hosts including OpenClaw, Hermes, Codex, and Cursor (see `cai.com/developers.html` for the current host list). Once installed, the agent can call `GET /get-identity` , `POST /get-wallet-balances` , `POST /wallet-custodial-transfer` , and the rest of the CAI surface — without the user pasting a private key in chat. The contract an agent reads first is `cai.com/skill.md` . It's the canonical source-of-truth for what CAI can do, written in a format agents parse. The companion artifact is the A2A Agent Card at `cai.com/.well-known/agent.json` — that's how agents discover CAI in agent-to-agent registries. **Comment below with:** Every comment on this article gets read. Bug reports will be replied to within 24 hours. Friction points shape what we document next. Documentation: `cai.com/skill.md` · `cai.com/developers.html` · `cai.com/app` to sign up.