fix(coding-agent): retry OpenAI Responses early EOF

closes #6727

packages/ai/CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Fixed
 
 - Fixed Kimi Coding subscription models to report API-equivalent implied costs when models.dev reports zero pricing.
+- Fixed OpenAI Responses early stream endings to be classified as retryable provider errors ([#6727](https://github.com/earendil-works/pi/issues/6727)).
 
 ## [0.80.10] - 2026-07-16
 

packages/ai/src/utils/retry.ts

@@ -68,6 +68,7 @@ const RETRYABLE_PROVIDER_ERROR_PATTERN = buildProviderErrorPattern([
 	// (#4433); Bedrock/Smithy can throw an HTTP/2 no-response error (#3594).
 	"ended without",
 	"stream ended before message_stop",
+	"stream ended before a terminal response event",
 	"http2 request did not get a response",
 
 	// Provider-requested retry delay cap failures should flow through the outer

packages/ai/test/retry.test.ts

@@ -9,6 +9,7 @@ const bedrockExplicitRetryMessage =
 const nvidiaNIMResourceExhaustedMessage = "ResourceExhausted: Worker local total request limit reached (288/48)";
 const bunFetchSocketClosedMessage =
 	"The socket connection was closed unexpectedly. For more information, pass `verbose: true` in the second argument to fetch()";
+const openAIResponsesEarlyEofMessage = "OpenAI Responses stream ended before a terminal response event";
 
 describe("provider retry classification", () => {
 	it("matches explicit provider retry guidance", () => {
@@ -37,6 +38,14 @@ describe("provider retry classification", () => {
 		).toBe(true);
 	});
 
+	it("matches OpenAI Responses streams that end before terminal events", () => {
+		expect(
+			isRetryableAssistantError(
+				fauxAssistantMessage("", { stopReason: "error", errorMessage: openAIResponsesEarlyEofMessage }),
+			),
+		).toBe(true);
+	});
+
 	it("keeps provider limit errors non-retryable", () => {
 		expect(
 			isRetryableAssistantError(

packages/coding-agent/CHANGELOG.md

@@ -10,6 +10,7 @@
 
 - Fixed obsolete custom UI, custom tool, and custom editor examples in the extension documentation ([#6735](https://github.com/earendil-works/pi/issues/6735)).
 - Fixed Kimi Coding sessions to show API-equivalent implied costs with the subscription indicator.
+- Fixed OpenAI Responses early stream endings to trigger automatic retry instead of ending the agent run ([#6727](https://github.com/earendil-works/pi/issues/6727)).
 
 ## [0.80.10] - 2026-07-16