---
ref: tool:close/subscribe-to-sequence
name: Subscribe a contact to a sequence
company: company:close
workflows: []
access: [api]
tags: [capability:enroll-in-sequence, category:crm, has:api]
docs: https://developer.close.com/api/resources/sequences/create-subscription
updated: 2026-09-27
---

# Subscribe a contact to a sequence

Enrolls a contact in a sequence (workflow), whose timed email and call steps run until the contact replies.

Note: Starts real outbound email: confirm the sequence, sender and contact first. The MCP server has no tool for this call.

## Set up

Use the first option your agent supports.

### API (official)

- Base URL: https://api.close.com/api/v1
- Endpoint: `POST /sequence_subscription/`
- Auth: send the header `Authorization: Basic $CLOSE_API_KEY`
- Docs: https://developer.close.com/api/overview

Note: `CLOSE_API_KEY` holds the base64 of `<api key>:`, the key with a trailing colon.

Before anything else, confirm access with the cheapest read-only call, like a list or a search. Never send or change anything to test access.

## Rules

- Ask the user before anything that sends messages, costs money, or changes data, and say how many records it touches. One approval covers a batch the user has seen.
- Never print API keys.