Use an exponential delay for API retries

Author: mrubens

.changeset/tame-walls-kiss.md

@@ -0,0 +1,5 @@
+---
+"roo-cline": patch
+---
+
+Use an exponential backoff for API retries

src/core/Cline.ts

@@ -793,7 +793,7 @@ export class Cline {
 		}
 	}
 
-	async *attemptApiRequest(previousApiReqIndex: number): ApiStream {
+	async *attemptApiRequest(previousApiReqIndex: number, retryAttempt: number = 0): ApiStream {
 		let mcpHub: McpHub | undefined
 
 		const { mcpEnabled, alwaysApproveResubmit, requestDelaySeconds } =
@@ -887,21 +887,29 @@ export class Cline {
 			// note that this api_req_failed ask is unique in that we only present this option if the api hasn't streamed any content yet (ie it fails on the first chunk due), as it would allow them to hit a retry button. However if the api failed mid-stream, it could be in any arbitrary state where some tools may have executed, so that error is handled differently and requires cancelling the task entirely.
 			if (alwaysApproveResubmit) {
 				const errorMsg = error.message ?? "Unknown error"
-				const requestDelay = requestDelaySeconds || 5
-				// Automatically retry with delay
-				// Show countdown timer in error color
-				for (let i = requestDelay; i > 0; i--) {
+				const baseDelay = requestDelaySeconds || 5
+				const exponentialDelay = Math.ceil(baseDelay * Math.pow(2, retryAttempt))
+
+				// Show countdown timer with exponential backoff
+				for (let i = exponentialDelay; i > 0; i--) {
 					await this.say(
 						"api_req_retry_delayed",
-						`${errorMsg}\n\nRetrying in ${i} seconds...`,
+						`${errorMsg}\n\nRetry attempt ${retryAttempt + 1}\nRetrying in ${i} seconds...`,
 						undefined,
 						true,
 					)
 					await delay(1000)
 				}
-				await this.say("api_req_retry_delayed", `${errorMsg}\n\nRetrying now...`, undefined, false)
-				// delegate generator output from the recursive call
-				yield* this.attemptApiRequest(previousApiReqIndex)
+
+				await this.say(
+					"api_req_retry_delayed",
+					`${errorMsg}\n\nRetry attempt ${retryAttempt + 1}\nRetrying now...`,
+					undefined,
+					false,
+				)
+
+				// delegate generator output from the recursive call with incremented retry count
+				yield* this.attemptApiRequest(previousApiReqIndex, retryAttempt + 1)
 				return
 			} else {
 				const { response } = await this.ask(

src/core/__tests__/Cline.test.ts

@@ -730,25 +730,19 @@ describe("Cline", () => {
 				const iterator = cline.attemptApiRequest(0)
 				await iterator.next()
 
+				// Calculate expected delay for first retry
+				const baseDelay = 3 // from requestDelaySeconds
+
 				// Verify countdown messages
-				expect(saySpy).toHaveBeenCalledWith(
-					"api_req_retry_delayed",
-					expect.stringContaining("Retrying in 3 seconds"),
-					undefined,
-					true,
-				)
-				expect(saySpy).toHaveBeenCalledWith(
-					"api_req_retry_delayed",
-					expect.stringContaining("Retrying in 2 seconds"),
-					undefined,
-					true,
-				)
-				expect(saySpy).toHaveBeenCalledWith(
-					"api_req_retry_delayed",
-					expect.stringContaining("Retrying in 1 seconds"),
-					undefined,
-					true,
-				)
+				for (let i = baseDelay; i > 0; i--) {
+					expect(saySpy).toHaveBeenCalledWith(
+						"api_req_retry_delayed",
+						expect.stringContaining(`Retrying in ${i} seconds`),
+						undefined,
+						true,
+					)
+				}
+
 				expect(saySpy).toHaveBeenCalledWith(
 					"api_req_retry_delayed",
 					expect.stringContaining("Retrying now"),
@@ -757,12 +751,14 @@ describe("Cline", () => {
 				)
 
 				// Verify delay was called correctly
-				expect(mockDelay).toHaveBeenCalledTimes(3)
+				expect(mockDelay).toHaveBeenCalledTimes(baseDelay)
 				expect(mockDelay).toHaveBeenCalledWith(1000)
 
 				// Verify error message content
 				const errorMessage = saySpy.mock.calls.find((call) => call[1]?.includes(mockError.message))?.[1]
-				expect(errorMessage).toBe(`${mockError.message}\n\nRetrying in 3 seconds...`)
+				expect(errorMessage).toBe(
+					`${mockError.message}\n\nRetry attempt 1\nRetrying in ${baseDelay} seconds...`,
+				)
 			})
 
 			describe("loadContext", () => {