add-contact-channel

name	add_contact_channel
description	Attach a channel (email, phone, whatsapp, signal, sms, website, social) to a contact.
when_to_use	- "Oma hat eine neue Handynummer …" → add_contact_channel(contact_id=N, kind='phone', value='…', label='mobile'). - "speicher die Email von Müller GmbH: kontakt@..." → add_contact_channel(contact_id=N, kind='email', value='…'). - When an unknown inbound channel arrives that the user wants linked to an existing contact instead of a new one. - If the (kind, value) is already attached to a DIFFERENT contact you'll get an error — that's a duplicate, fix the contact_id instead of forcing it through. - Always call find_person first to get the right contact_id.
inputs	{"contact_id":{"type":"integer","required":true},"kind":{"type":"string","required":true,"description":"One of 'email' | 'phone' | 'whatsapp' | 'signal' | 'telegram' | 'sms' | 'website' | 'social'."},"value":{"type":"string","required":true,"description":"The channel value. Auto-normalised (emails lowercased, phones digit-stripped)."},"label":{"type":"string","required":false,"description":"'primary' | 'work' | 'home' | 'mobile' | etc."}}
outputs	{"channel_id":{"type":"integer"},"contact":{"type":"object"}}
permissions	["admin","member","restricted"]
side_effects	1 row in contact_channels
tags	["contacts","mutation"]

add_contact_channel

Channels are unique on (kind, value) — the same email/phone can't be attached to two different contacts. Trying to do so raises a clear "already linked to contact X" error so the LLM can decide whether to merge or pick the existing contact.