Endpoint POST /api/messages/cancel
Cancels all AI messages currently being processed in a project. This stops the AI agent mid-execution and marks messages as cancelled.
Authentication Requires a valid Clerk session token. See Authentication for details.
Request Body The Convex ID of the project containing messages to cancel.
Response Always true if the request was processed.
true if messages were cancelled, false if no messages were processing.
Array of Convex IDs for cancelled messages. Only present if cancelled is true.
Request Example const response = await fetch ( '/api/messages/cancel' , { method: 'POST' , headers: { 'Content-Type' : 'application/json' , }, body: JSON . stringify ({ projectId: 'k57abc123def456' }) }); const data = await response . json (); if ( data . cancelled ) { console . log ( `Cancelled ${ data . messageIds . length } messages` ); }
Response Example 200 Messages Cancelled
200 No Messages Processing
401 Unauthorized
{ "success" : true , "cancelled" : true , "messageIds" : [ "k58xyz789ghi012" , "k59abc456def789" ] }
Cancellation Process When messages are cancelled:
Find processing messages
All messages with status: "processing" in the project are identified.
Send cancel events
Inngest cancel events are sent for each processing message.
Update status
Message status is updated to cancelled in the database.
Stop AI agent
The running AI agent receives the cancel signal and stops execution.
When to Use Cancellation
Wrong request User realizes they sent the wrong prompt or selected wrong files.
Too slow AI is taking too long and user wants to try a different approach.
Unexpected behavior AI is modifying files in an unexpected way.
Resource limits Need to stop to avoid hitting API rate limits.
UI Integration Typically called when the user clicks a “Cancel” or “Stop” button in the conversation sidebar:
const handleCancel = async () => { const response = await fetch ( '/api/messages/cancel' , { method: 'POST' , headers: { 'Content-Type' : 'application/json' }, body: JSON . stringify ({ projectId }) }); const data = await response . json (); if ( data . cancelled ) { // Show success message toast . success ( 'AI stopped' ); } else { // No messages were processing toast . info ( 'No AI requests to cancel' ); } };
Behavior Notes Cancellation is immediate - the AI agent stops as soon as it receives the cancel signal. Any partial changes are NOT rolled back.
If the AI already modified files before cancellation, those changes remain. You may need to manually undo unwanted changes.
Multiple Conversations This endpoint cancels all processing messages in the project, across all conversations. If you have multiple conversations with active AI requests, they will all be cancelled.
Learn More