1. Connect a tracker under Account settings > Integrations
Pick the tracker, name the connection, say where tickets go (a GitHub owner/repo, a GitLab project path or id, a Jira project key, a Linear team id) and paste a token. The token is stored for sending only and never shown again; change it by deleting and re-adding the connection. Each provider's how-to lists the token scope it needs.
2. Press Test connection
It reads the project with your token and reports what it found, or why it failed (wrong scope, repository with Issues turned off, unknown project key). It creates nothing anywhere. A self-hosted GitLab or Jira must be reachable from the public internet over https; private addresses are refused.
3. File from an issue or an incident
On an Errors issue page, the Tickets section offers Create ticket per connection; in the Status dashboard, each incident row does the same. The ticket carries the title, a measured body (counts, first and last seen, status, timeline) and a permalink back, plus the label realuptime and any default labels you set (Linear labels are ids, so the label is skipped there).
4. Once per connection, by construction
Pressing Create ticket again for the same issue or incident on the same connection returns the existing link instead of opening a second ticket, even if two people click at once. The link is shown on the issue or incident and in the account audit log.
Go deeper
The full reference lives in the docs: API documentation. Error codes named above are each explained in the error-code reference.