Give Claude a web index in about ninety seconds
Kaer runs a Model Context Protocol server. Point Claude Desktop, Claude Code, ChatGPT, Codex or Cursor at it and your assistant gets search, workflows, mail and calendar as tools — on your account, on your bill, revocable from one screen.
The Model Context Protocol solved the boring half of the integration problem: every assistant now speaks one dialect for "here are some tools you can call". The interesting half is what you point it at. This is how to point Claude at ours.
Press this and it will check whether you are signed in, create a scoped key, and hand you the config block for the client you use. Nothing is created until you press Connect.
What your assistant gets
The tools on the endpoint are the product, exposed one-to-one. The defaults on a connection made from this page are deliberately the read-and-run half:
| Tool | What it does | Metered |
|---|---|---|
kaer_call_agent | Ask Kaer anything — it has the search index behind it. | Yes |
kaer_run_workflow | Run a workflow you have already built, by id. | Yes |
kaer_search_mail | Search connected mail. Cannot send, draft, label or delete. | No |
kaer_list_calendar_events | Read connected events. Cannot create or edit. | No |
Five more exist and are off by default, because a button in a blog post is not informed consent for them: driving the computer agent, generating images and video, calling private custom tools, Kaer Maps, and creating AI employees. Turn any of them on per key in Settings → Developer → MCP Tools.
By hand, if you would rather
The connect button is a convenience, not a requirement. The endpoint is ordinary MCP over streamable HTTP.
Claude Desktop — Settings → Developer → Edit Config:
{
"mcpServers": {
"kaer": {
"type": "http",
"url": "https://app.kaer.ai/api/mcp",
"headers": {
"Authorization": "Bearer kaer_sk_…",
"Accept": "application/json, text/event-stream"
}
}
}
}Claude Code — one command:
claude mcp add --transport http kaer https://app.kaer.ai/api/mcp \
--header "Authorization: Bearer kaer_sk_…"ChatGPT — Settings → Connectors → Add custom connector, with the URL and the Authorization header as separate fields. Cursor takes the same JSON as Claude Desktop in ~/.cursor/mcp.json.
Two things that are unusual about this server
Cookies are rejected outright. Send a browser session cookie to /api/mcp and the request fails with a 403 telling you to use a bearer key without cookies. This is not fussiness. An MCP endpoint that accepted ambient session auth would be reachable by any page you had open, which turns a cross-site request into a tool call against your account.
Exact-once is available but not compulsory. Send an Idempotency-Key header on a tools/call and the result is recorded against it: a retry with the same key replays the stored response rather than running the tool twice, for seven days. Send nothing and you get ordinary at-most-once behaviour, which is what every other MCP server gives you. Standard clients do not send the header — it is not in the MCP spec — so this matters mainly if you are writing the client yourself and want a network blip to be safe to retry.
What it costs
Connecting is free and the read-only tools are unmetered. Metered tools bill at their normal rates against the same account, so a search through MCP is the same $0.005 as a search through the REST API — the full comparison against other providers is in what a web search API should cost in 2026.
Keys are capped at ten active per account and every one of them is revocable from a single screen. If you are weighing whether an index-backed API is the right shape at all, search API or SERP scraper is the argument in full.
Frequently asked questions
What is the Kaer MCP server?
An HTTP endpoint at /api/mcp that implements the Model Context Protocol. Any MCP client can connect to it with a Kaer API key and gets a set of tools: ask Kaer, run a workflow, search mail, read calendar events, and more depending on the scopes on the key.
Which clients does it work with?
Anything that speaks MCP over streamable HTTP. Tested with Claude Desktop, Claude Code, ChatGPT custom connectors, Codex and Cursor.
How is the connection authenticated?
With a kaer_sk_ API key sent as an Authorization bearer header. The key is bound to your Kaer account, carries an explicit scope list, and is revocable at any time from Settings → Developer → MCP Tools. Browser cookies are rejected outright — a session can never be an MCP credential.
What does it cost to connect?
Connecting is free. Tools that do metered work — searches, agent calls, media generation — bill at the same rates as the rest of the product, against the same account. Read-only tools like mail search and calendar reads are unmetered.
