CosVoice for Grok Bot, Claude, ChatGPT, and Cursor

Give your Chief of Staff a phone. CosVoice gives an AI assistant its own real phone number (in your area code) and its own email address. The assistant can place calls for you, book restaurants by phone, answer the calls you miss, and read a written summary of every call. The voice on the line is Grok Voice, full duplex, and it always says it is an AI assistant when asked.

Website: https://cosvoice.com · Setup page written for the assistant: https://cosvoice.com/skill

Connect in one paste

https://cosvoice.com/mcp

Add that as a remote MCP server (Streamable HTTP). CosVoice uses OAuth 2.1 with PKCE and dynamic client registration, so a CosVoice page opens, you sign in, click Allow, and the assistant is connected. There is no API key to copy.

Client	How
Grok Bot / Grok	Settings → Plugins → add a custom MCP server by URL, or install this plugin
Claude (web, desktop, Code)	Add a custom connector / claude mcp add --transport http cosvoice https://cosvoice.com/mcp
ChatGPT	Settings → Connectors → add MCP server by URL (developer mode)
Cursor	Add to Cursor or paste the URL under Settings → MCP

Clients that only support a static header can use a key from Settings → Connect your agent as Authorization: Bearer cv_live_….

Then let the assistant set itself up

Send it: "Set up my CosVoice line in area code 949. Call it Lloyd."

It calls search_numbers, shows you options, and create_line. Payment comes first: if no plan is on file, create_line returns a checkout link for you to complete, then the number is issued.

What it can do

Tool	What it does
get_account, search_numbers, create_line	First-run setup: check the account, find numbers in an area code, create the line
place_call	Call a real number and hold a live conversation on your behalf (async; poll get_call)
book_reservation	Book a table by phone with a time window, fallbacks, seating, occasion, dietary notes
get_call, list_calls, list_reservations, annotate_call	Summaries, structured details, transcripts, outcomes
send_text, list_messages	Texts from and to the line (STOP respected)
list_emails, get_email, forward_email	The line's own inbox
list_contacts, add_contact, remove_contact	Owner, approved, VIP, blocked callers
get_settings, update_settings, set_webhook	Persona, voice, greeting, standing instructions, call.completed webhooks
ack_instructions	Texts you send the line from your own phone arrive as instructions on every tool result; acknowledge when handled
list_history, recent_activity, list_integrations	Unified history, catch-up since a timestamp, partner tools

What this repo contains

• skills/cosvoice/SKILL.md — the skill (same text as https://cosvoice.com/skill)
• .mcp.json — the hosted server entry (type: http, OAuth)
• .grok-plugin/plugin.json and .claude-plugin/plugin.json — plugin manifests
• server.json — the official MCP Registry entry (com.cosvoice/cosvoice)

No code runs on your machine. The plugin only points your client at the hosted server.

Rules the line follows

Never pays or reads out a card. Always says it is an AI assistant when asked. Uses its own number and email as the callback unless you say otherwise. Never claims a booking unless the call outcome says so. Respects STOP for texts.

Pricing

Starter $29/mo (60 min), Plus $69/mo (200 min), Pro $149/mo (600 min), overage $0.25/min. One number per paid month. Details: https://cosvoice.com/pricing

Links

Trust and safety: https://cosvoice.com/trust · FAQ: https://cosvoice.com/faq · Privacy: https://cosvoice.com/privacy · Terms: https://cosvoice.com/terms · Support: hello@cosvoice.com

MIT licensed. CosVoice is a product of MimesisIQ.