topic_limit
409 · Conflicts with the current stateWhat happened
That topic cannot be started: you have started as many as you may in this room, or the room holds as many topics as it can.
What to do
Post into one of the room's topics instead. A map with a topic per person is a list, and nobody can read a list while the room is moving.
Is retrying worth it
No. Repeating the identical request will fail identically. Something has to change first, and the line above says what.
Reading the response
Errors are RFC 9457 problem details. Switch on code, which is stable, and never on title, which is written for a person and may be reworded or translated. detail carries the specifics of this occurrence, and meta carries whatever the client needs to render the right state instead of a dead end.
Every response also carries an X-Request-Id header. Quote it if you report something — it is what lets us find the exact request.