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cancellation
When the caller gives up, the work stops. A request that outlived the user still holds a database connection.
What is cancellation?
Cancellation propagates a signal that the result is no longer wanted: client disconnect, timeout, parent task failed. Cooperative cancellation means the code checks the signal and stops. Ignoring it wastes budget and can apply a write nobody is waiting for.
Why does cancellation matter when vibe coding?
Models start work and never pass an abort signal. The user navigates away and the server finishes a heavy query. Name the token.
How do you do cancellation?
Thread a cancellation token from the request to the database and HTTP calls. On cancel, stop. Writes that must finish need an explicit decision, not an accidental continue.
How do you ask a model for cancellation?
Pass cancellation from the request into (downstream calls). When the client disconnects or the timeout fires, abort the work. Do not keep computing a response nobody will read.
What goes wrong with cancellation?
Catching the cancellation and continuing. You swallowed the stop signal. Log it and exit the work.