Remind SignUpGenius group members to fill open slots

1. Open the sign-up from the Created tab and scroll through the slots, or click the Reports icon, select the sign-ups and view the report with blank slots to see filled and open slots together.
2. In the Manage Sign Up toolbar at the top of the sign-up, click Send a Message and choose Email People Participating in a Sign Up.
3. Pick the option for people who have not signed up, then type the open dates and times into the message yourself.
4. After sending, check the Messages dashboard, where Pending means SignUpGenius staff are reviewing the email, then the Sent tab, where Message Analytics shows which addresses bounced.
5. Each sign-up needs its own pass, every week until the event, and the list of open shifts in last week's email is already wrong by the time you reuse it.

Every Monday, check my active PTA sign-ups for empty slots in the next 14 days and email the group members who have not signed up, listing the open shifts.

1. 01

   Find sign-ups that still need people

   list_signups with status active gives the filled and wanted counts. The agent drops sign-ups that are already full or whose next date is outside your window, and lists sign-ups with no group as "cannot nudge" instead of guessing who should get the email.

2. 02

   List only the gaps that matter now

   get_signup with open_only returns the empty slots. The agent keeps the ones inside your window, drops times that have already passed, and groups the rest by day so the email reads "Friday 12 March: 2 spots at 10:00, 3 at 14:00".

3. 03

   Write one email per sign-up

   The subject names the event and how many spots are left, and the body lists the open shifts with the sign-up link from get_signup. The agent keeps it short and leaves out who already signed up.

4. 04

   Send to the right people, with your OK

   send_message goes to not_signed_up only, after you approve the text. With confirmation switched off for the Monday run, the agent sends the same way and tells you the count afterwards.

5. 05

   Do not resend a held email

   When SignUpGenius holds a message as Pending for review, the agent reports it and does not send it again, since the help center warns that repeat attempts are also paused and can reach the group twice.

Book fair volunteers (PTA): 6 open spots in the next 14 days.
Emailed 31 members who have not signed up after your OK; 2 skipped with no email address.
Spring bake sale (PTA): full, nothing sent.
Field day helpers: no group assigned, so no nudge was sent. Assign a group to include it next week.

• SignUpGenius Send a Message offers four audiences: the entire group, specific individuals, people who signed up and people who have not signed up.
• SignUpGenius staff review some outgoing emails, which then show as Pending in Messages, and the help center says not to resend because each new attempt is paused too.
• The SignUpGenius Sent tab keeps messages from the past 30 days with Delivered or Bounced per address, and seeing who opened and clicked needs a Gold, Platinum or Enterprise plan.
• Text messages from SignUpGenius need a paid plan and reach only members who opted in; everyone else gets the same message by email.

send_message asks for your OK by default. To run it weekly without you, switch confirmation off for that tool in your dashboard.

Sources: SignUpGenius Help: Send Messages to Group Members and Participants · SignUpGenius Help: View Reminder Settings and Emails · SignUpGenius Help: View Sent Email Messages · SignUpGenius Help: Manage Paused Messages

curl https://cotlet.dev/api/v1/signupgenius/send_message \
  -H "Authorization: Bearer $COTLET_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"signup_id":"50471160","recipients":"not_signed_up","subject":"Book fair: 6 spots still open next week","body":"Hi all, we still need help on Friday 12 March: 2 spots at 10:00 and 3 at 14:00, plus 1 on Saturday at 9:00. Pick one at the sign-up link."}'

{
  "signup_id": "50463821",
  "recipients": "not_signed_up",
  "sent": 14,
  "skipped_no_email": 1
}

MCP: add https://cotlet.dev/mcp/v1 with the same key; the tool is signupgenius_send_message. Example data.

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