Tellnod

npx add-mcp 'https://mcp.tellnod.com/mcp'

Endpoint and transport

• Address: https://mcp.tellnod.com/mcp
• Transport: Streamable HTTP. There is nothing to install or run locally.
• Clients: Claude (custom connector) and ChatGPT (custom MCP server). Setup steps: Connect.
• Interactive cards: in clients that support MCP Apps, tools attach a ui://tellnod/… card; other clients receive the same result as text.

Authentication

Sign-in uses OAuth 2.1 with dynamic client registration, so clients register themselves and you sign in with Google in the browser. Access tokens are bound to the MCP server’s address and are refused anywhere else.

A connected client can read and draft. Sending is not an OAuth permission. Scheduling a send requires a person to press Confirm on the card or on the web confirmation page, so a token alone can never send email.

Tools

Every tool declares readOnlyHint, destructiveHint, idempotentHint and openWorldHint, so the client can show you which calls change data.

Read-only

• get_workspace, get_overview: account, plan, limits and what to do next.
• fetch_brand: reads logo, colors and fonts from your website.
• search_contacts, get_contact, list_segments, estimate_audience: find people and size an audience before saving it.
• render_preview, preview_inbox, preview_channels, list_templates: the real email, the inbox line and starting templates.
• check_domain: DNS status for your sending domain.
• get_send, list_sends, get_campaign_results, compare_campaigns: send status and results.

Writes

• save_brand, confirm_brand: store the brand used in every email.
• import_contacts, tag_contacts, create_segment: contacts with consent status, and saved audiences.
• create_message_draft, update_message_draft, apply_template: write and revise the email.
• add_domain, remove_domain: send from your own domain.
• send_test: a test email to yourself (up to 20 a day).
• prepare_send, prepare_resend: freeze the recipients and show the confirmation card.
• cancel_send: cancel a scheduled send.

confirm_send is visible only to the card, not to the model, so the assistant cannot complete a send by itself.

The two-step send

1. prepare_send freezes the recipient list and returns a confirmation bound to the workspace, the person, the message and that exact list.
2. The confirmation card shows the recipient count, who is excluded and why, the send time and the compliance checklist.
3. Pressing Confirm schedules the send. The confirmation is single-use and expires after 30 minutes; preparing again issues a new one.
4. “Send now” waits 5 minutes, and any scheduled send can be cancelled until it goes out.

Limits and safeguards

• Shared sending domain (an address such as hello@yourshop.tellnodmail.com): up to 500 recipients per campaign and 1,000 emails a month. Your own verified domain lifts these limits.
• Free plan: 500 contacts and 2,000 emails a month.
• Sends pause automatically at a 0.1% complaint rate or a 2% bounce rate.
• Unsubscribe links, one-click unsubscribe headers and a postal address are added to every campaign.

WhatsApp and LINE tools

WhatsApp and LINE tools use the same contacts, preview and two-step send, and appear in the tool list when each channel opens: WhatsApp next, then LINE. See LINE MCP server.

FAQ

Is the Tellnod MCP server open source?

The server is a hosted service. The email preview renderer, preview-kit, is planned as an open-source package.

Can I use it from my own MCP client?

Any client that supports remote MCP servers over Streamable HTTP with OAuth sign-in can connect. Cards render only in clients that support MCP Apps.

Can an API key send email through the MCP server?

No. There are no send-capable API keys; every send needs a person to press Confirm.