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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. Hippo doesn't currently expose this surface - that's the gap.
Hippo's design philosophy is the opposite of feature-creep: do the keep-in-touch reminder loop perfectly and stop. Contact Book does the same loop alongside life events, gifts, family graph, and a journal. Pick Hippo if you want the simplest possible nudge tool; pick us if you want the texture too.
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. Hippo 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 Hippo | |
|---|---|---|
Stay-in-touch reminders | ||
Life events + gifts | ||
Family / relationship graph | ||
Journal | ||
Hosted in Germany | ||
Free tier |