Win a second open with a subject-line resend

Win a second open with a subject-line resend

Set up the tools below, then run the steps in order for the user.

Inputs

Ask the user for these before you start.

• send_id: the Brew send to follow up
• email_id: the email it sent
• original_subject: its subject line
• wait_days: how long to wait after the first send, e.g. 3

Set up

Brew (tool:brew/create-audience-from-events, tool:brew/send-email)

Use the first option your agent supports.

MCP (official, remote)

Add this server to your agent's MCP settings, then sign in when asked.

{ "mcpServers": { "brew": { "url": "https://brew.new/api/mcp" } } }

• Create an audience from email events: call the MCP tool create_audience_from_events
• Send an email: call the MCP tool send_email

CLI (official)

Install the command, then confirm it runs.

brew install getbrew/tap/brew-cli
brew-cli --version

• Create an audience from email events: run brew-cli audiences from-events
• Send an email: run brew-cli emails send

Set $BREW_API_KEY in your environment first (get a key: https://brew.new/settings/api).

Create a message (Anthropic, tool:anthropic/create-message)

Use the first option your agent supports.

CLI (official)

Install the command, then confirm it runs.

curl -fsSL https://claude.ai/install.sh | bash
claude --version

Run claude -p.

API (official)

• Base URL: https://api.anthropic.com
• Endpoint: POST /v1/messages
• Auth: send the header x-api-key: $ANTHROPIC_API_KEY
• Get a key: https://platform.claude.com/settings/keys

Make one read-only call to each tool to confirm access.

Steps

1. Segment with Create an audience from email events (Brew). Build an audience of the contacts in send_id who have not opened after wait_days, and wait until it has built.
2. Rewrite with Create a message (Anthropic). Write two alternatives to original_subject that make a different promise. Show them to the user.
3. Resend with Send an email (Brew). Send email_id with the chosen subject line to that audience, after the user approves.

Done when

• Only unopened contacts received the resend.
• The user has the number of contacts it went to.

Rules

• Only use the tools listed above.
• Ask the user before anything that sends messages, costs money, or changes data.
• Never print API keys.