Can Claude / ChatGPT / Cursor use Contact Book directly?

Yes, via the MCP server. It's a stdio JSON-RPC server that wires into Claude Desktop, Cursor, or any MCP-aware client in five lines of config. The list of tools matches your data model 1:1 - whatever a CRUD type exposes in the UI is exposed identically to the agent.

Do agent calls share the same auth + access controls?

Yes. The MCP server authenticates with the same JWT or PAT a human session uses. Sharing rules, org membership, rate limits, suspicion bans - all of it applies. There's no "agent backdoor" that bypasses the access matrix.

Is there an audit trail for agent actions?

Yes. Every mutation goes through the same audit-log path as a UI click. The transport (UI / API / CLI / MCP) is recorded as channel metadata so you can filter "what did the agent do this hour" from your account history.

Can I rate-limit an agent separately from a human?

Per-token rate limits apply, so you can issue an agent its own PAT and cap it independently. The shared user-level bucket also caps total throughput, so a runaway loop can't drain your whole account. The CLI's auto-update channel marker means you can also see in audit which version is calling.

Does the MCP / API surface cost extra?

No. Same plan, same surface. We don't paywall the agent - it's the same product, the same schema, the same access gates. If a plan can do X in the UI, it can do X via MCP.

Contact Book

Compare

Contact Book: the agent-friendly alternative to Google Contacts

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

Agentic alternative

Personal CRM

Comparison

Julia YukovichCo-Founder + CEO

·April 18, 2026·

2 min read

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. Google Contacts doesn't currently expose this surface - that's the gap.

At a glance

Google Contacts is excellent at what it does: keeping a phone-shaped address book in sync across your devices. Contact Book is built for the next layer up - logging conversations, gifts, life events, and follow-ups so the relationships you care about don't quietly drift apart. If you only need names + numbers on your phone, stick with Google. If you find yourself opening a contact card and asking what did we last talk about, you'll outgrow Google Contacts the same week you try us.

Agent surface

What 'agent-friendly' actually means in practice

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. Google Contacts 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.

Contact Book vs Google Contacts: agent-readiness comparison

	Ours Contact Book	Theirs Google Contacts
Stores names + phone numbers
Syncs across devices
Conversation log per contact
Life events + birthdays		Birthdays only
Gifts given / received
Follow-up reminders
Stay-in-touch cadence
Pets attached to contacts
Custom fields per contact		Limited
Hosted in Germany
Used by your phone's dialer
Free tier

When to pick which

Pick Contact Book when

You want a memory layer on top of your address book, not just a phonebook.

You like to log who you spoke with and what about, so the next conversation picks up cleanly.

Birthdays, gifts, family relationships, pet names - all of it matters, and you want it in one place.

Your data should live in Germany, exportable + deletable on your own.

Pick Google Contacts when

You only need names, numbers, and email synced to your phone's dialer + Gmail autocomplete.

Everything else lives in Calendar, Photos, and Drive, and you want one Google account to manage it.

Free + integrated with Android / Gmail is the only thing that matters to you.

Agentic-integration questions

What an agent-builder asks before wiring a tool into Claude / ChatGPT / Cursor.

Start with Contact Book

Free plan, no credit card. We host in Germany. Export + delete are self-serve.

Written by

Julia Yukovich

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.

julia.yukovich at aicuflow dot comLinkedIn