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Same product, same surface for humans and AI agents. MCP server + CLI + drop-in clients in 15 languages.

Contact Book ships an MCP server you can wire into Claude Desktop or any MCP client in five lines. The same auth + access gates apply, the same audit log records every action, the same rate limits apply. Notion doesn't currently expose this surface - that's the gap.
A Notion CRM template is a great starting point. It's free, it's flexible, and it works for the first month. After that, three things tend to break: cadence reminders are flaky, life-event reminders rely on calendar tricks, and adding a custom field to a contact gradually fills the page with property pills nobody cleans up. Contact Book is the next step up - the same idea, but with the relationship-specific surface baked in.
Agent surface
Contact Book ships an MCP server, a CLI, and drop-in clients in 15 languages. They're auto-generated from the same schema your UI uses; the auth, the access gates, the rate limits, the audit log all apply identically whether you're clicking buttons or calling the API. Notion doesn't currently expose this surface, which is the gap a serious agent integration trips over - the agent ends up scraping the UI through a browser, which is fragile, slow, and silently bypasses everything below.
Agentic-integration questions
Free plan, no credit card. We host in Germany. Export + delete are self-serve.

Written by
Co-Founder + CEO
Julia is one of the Co-Founders. She handles design, product direction, and most of the support replies that arrive in the morning.
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| Ours Contact Book | Theirs Notion | |
|---|---|---|
Custom fields per contact | ||
Native cadence reminders | ||
Life events with built-in reminders | ||
Activity / conversation log | Manual | |
Live multi-tab updates | ||
Mobile-first quick add | Slow | |
Free tier | ||
Hosted in Germany | ||
Build it yourself |