Join links deep dive (coach)

What a join link is

A CoachJoinLink is a permanent URL that lets anyone sign up to your roster, or lets an existing athlete switch their coach to you. The URL pattern is yousuli.co/join/<slug>, where <slug> can be an 8-character random string or a vanity slug you choose (uclatri, coach-jenny-spring, etc.).

Default link vs custom links

• Default link is created automatically the first time you visit the Athlete join links page (/coach/join-links/). The slug is random and not editable. Use this as your stable evergreen link.
• Custom links are anything you create after that. You pick the slug (3 to 40 characters, lowercase, digits, hyphens), and optionally set an expiry date and a max signup cap.

What happens when someone clicks the link

The view at /join/<slug>/ is auth aware:

1. Anonymous visitor: sees the signup form (first name, last name, email, password, optional anthros). On submit, a new athlete account is created and they are auto-added to your roster.
2. Logged-in athlete already on another coach's roster: sees a confirmation page explaining the switch (data stays, coach pointer flips, premium cascade may apply). One click finishes the switch.
3. Logged-in athlete already on YOUR roster: redirected to their dashboard. No-op.
4. Logged-in coach or admin: sees a friendly error explaining that athlete join links are for athletes only.

Expiry and caps

• Expiry date is optional. After the date, the link returns the "expired" invalid page.
• Max uses is optional. Once the cap is hit, new visitors see the "capped" invalid page. Useful for "first 30 signups" promos.
• Revoke is permanent and is intended for compromised or stale links. Revoked links return an "unavailable" page.

Rate limiting

The accept endpoint is rate limited to 30 requests per hour per IP to defend against bot signups. Real human traffic is unaffected.

Premium cascade on coach switch

If a switching athlete had coach grant premium from the previous coach, that grant ends when the relationship ends. Premium they paid for directly is untouched. See Switching coaches explained.