MCP

Send & Retain is built to be driven over MCP — from Claude Code or a claude.ai connector — so you can set up domains, author templates, send email, and build automations in natural language. The same tools power the in-app copilot chat.

Connecting and scope

Authentication is OAuth 2.1 — there is no token to mint, copy, or store. Point a client at https://sendandretain.com/api/mcp and it discovers the authorization server itself, then sends you to a browser to approve. See Connecting for the per-client steps.

A connected session is always workspace-scoped with write access: every company in the org, every email_* tool. Because of that, project-scoped tools need an explicit projectId — call email_list_projects first and pass the company's projectId on each call.

What you can do

The toolset (email_*) covers the whole product. A sampling:

• Setup — email_get_connection_status, email_connect_provider (returns the settings URL — a human enters credentials), email_create_domain, email_verify_domain, email_create_sender, email_create_api_key.
• Templates — email_create_template, email_render_template, email_publish_template_version, email_send_template_test.
• Sending & observability — email_send_email (one recipient, published template), email_get_message, email_search_messages, email_get_email_metrics.
• Contacts & events — email_upsert_contact, email_import_contacts, email_emit_contact_event.
• Automations — email_create_automation, email_add_automation_steps, email_set_automation_status, email_set_ab_test.
• Suppression — email_list_suppressions, email_add_suppression, email_remove_suppression.

Guardrails

There's no approval queue — guardrails are built into the tools instead:

• Automations are created paused; enabling is a separate confirm: true call.
• Provider keys cannot be set over MCP — email_connect_provider hands back the settings-page URL for a human.
• Each project has a sendsPaused kill switch plus daily and monthly send caps.
• Complaint suppressions are never removable.