From e71b55ec69971dc3b40543c4579465c85802c4fb Mon Sep 17 00:00:00 2001 From: Jiahao Luo Date: Tue, 5 May 2026 15:13:46 +0800 Subject: [PATCH] fix: skip previous_response_id recovery when payload has function_call_output When a preflight ping fails or previous_response_not_found is returned, sub2api drops previous_response_id and retries. But if the payload contains function_call_output (tool results), the upstream API loses the response chain context needed to match tool_result to tool_use, causing 400: "No tool call found for function call output". Add hasFunctionCallOutput checks to both recovery paths: - Preflight ping failure recovery (forcePreferredConn path) - recoverIngressPrevResponseNotFound function --- backend/internal/service/openai_ws_forwarder.go | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/backend/internal/service/openai_ws_forwarder.go b/backend/internal/service/openai_ws_forwarder.go index 201073e0..173dac80 100644 --- a/backend/internal/service/openai_ws_forwarder.go +++ b/backend/internal/service/openai_ws_forwarder.go @@ -3104,6 +3104,12 @@ func (s *OpenAIGatewayService) ProxyResponsesWebSocketFromClient( if turnPrevRecoveryTried || !s.openAIWSIngressPreviousResponseRecoveryEnabled() { return false } + // 携带 function_call_output 的请求不能丢弃 previous_response_id： + // 上游 API 需要 response chain 来匹配 tool_result 与之前的 tool_use， + // 丢弃后会导致 "No tool call found for function call output" 400 错误。 + if gjson.GetBytes(currentPayload, `input.#(type=="function_call_output")`).Exists() { + return false + } if isStrictAffinityTurn(currentPayload) { // Layer 2：严格亲和链路命中 previous_response_not_found 时，降级为“去掉 previous_response_id 后重放一次”。 // 该错误说明续链锚点已失效，继续 strict fail-close 只会直接中断本轮请求。 @@ -3370,7 +3376,11 @@ func (s *OpenAIGatewayService) ProxyResponsesWebSocketFromClient( truncateOpenAIWSLogValue(pingErr.Error(), openAIWSLogValueMaxLen), ) if forcePreferredConn { - if !turnPrevRecoveryTried && currentPreviousResponseID != "" { + // 携带 function_call_output 的请求不能丢弃 previous_response_id： + // 上游 API 需要 response chain 来匹配 tool_result 与之前的 tool_use， + // 丢弃后会导致 "No tool call found for function call output" 400 错误。 + hasFCOutput := gjson.GetBytes(currentPayload, `input.#(type=="function_call_output")`).Exists() + if !turnPrevRecoveryTried && currentPreviousResponseID != "" && !hasFCOutput { updatedPayload, removed, dropErr := dropPreviousResponseIDFromRawPayload(currentPayload) if dropErr != nil || !removed { reason := "not_removed"