fix(hooks): improve session recovery for empty content messages

- Extract message index from Anthropic error messages (messages.N format)
- Sort messages by time.created instead of id for accurate ordering
- Remove last message skip logic that prevented recovery
- Prioritize recovery targets: index-matched > failedMsg > all empty
- Add error logging for debugging recovery failures

Fixes issue where 'messages.83: all messages must have non-empty content' errors were not being recovered properly due to incorrect message ordering and overly restrictive filtering.

🤖 GENERATED WITH ASSISTANCE OF [OhMyOpenCode](https://github.com/code-yeongyu/oh-my-opencode)

src/hooks/session-recovery/index.ts

@@ -2,6 +2,7 @@ import type { PluginInput } from "@opencode-ai/plugin"
 import type { createOpencodeClient } from "@opencode-ai/sdk"
 import {
   findEmptyMessages,
+  findEmptyMessageByIndex,
   findMessagesWithOrphanThinking,
   findMessagesWithThinkingBlocks,
   injectTextPart,
@@ -54,6 +55,12 @@ function getErrorMessage(error: unknown): string {
   return (errorObj.data?.message || errorObj.error?.message || errorObj.message || "").toLowerCase()
 }
 
+function extractMessageIndex(error: unknown): number | null {
+  const message = getErrorMessage(error)
+  const match = message.match(/messages\.(\d+)/)
+  return match ? parseInt(match[1], 10) : null
+}
+
 function detectErrorType(error: unknown): RecoveryErrorType {
   const message = getErrorMessage(error)
 
@@ -161,16 +168,26 @@ async function recoverEmptyContentMessage(
   _client: Client,
   sessionID: string,
   failedAssistantMsg: MessageData,
-  _directory: string
+  _directory: string,
+  error: unknown
 ): Promise<boolean> {
-  const emptyMessageIDs = findEmptyMessages(sessionID)
+  const targetIndex = extractMessageIndex(error)
+  const failedID = failedAssistantMsg.info?.id
 
-  if (emptyMessageIDs.length === 0) {
-    const fallbackID = failedAssistantMsg.info?.id
-    if (!fallbackID) return false
-    return injectTextPart(sessionID, fallbackID, "(interrupted)")
+  if (targetIndex !== null) {
+    const targetMessageID = findEmptyMessageByIndex(sessionID, targetIndex)
+    if (targetMessageID) {
+      return injectTextPart(sessionID, targetMessageID, "(interrupted)")
+    }
   }
 
+  if (failedID) {
+    if (injectTextPart(sessionID, failedID, "(interrupted)")) {
+      return true
+    }
+  }
+
+  const emptyMessageIDs = findEmptyMessages(sessionID)
   let anySuccess = false
   for (const messageID of emptyMessageIDs) {
     if (injectTextPart(sessionID, messageID, "(interrupted)")) {
@@ -262,15 +279,16 @@ export function createSessionRecoveryHook(ctx: PluginInput) {
       } else if (errorType === "thinking_disabled_violation") {
         success = await recoverThinkingDisabledViolation(ctx.client, sessionID, failedMsg)
       } else if (errorType === "empty_content_message") {
-        success = await recoverEmptyContentMessage(ctx.client, sessionID, failedMsg, ctx.directory)
+        success = await recoverEmptyContentMessage(ctx.client, sessionID, failedMsg, ctx.directory, info.error)
       }
 
-      return success
-    } catch {
-      return false
-    } finally {
-      processingErrors.delete(assistantMsgID)
-    }
+    return success
+  } catch (err) {
+    console.error("[session-recovery] Recovery failed:", err)
+    return false
+  } finally {
+    processingErrors.delete(assistantMsgID)
+  }
   }
 
   return {

src/hooks/session-recovery/storage.ts

@@ -42,7 +42,12 @@ export function readMessages(sessionID: string): StoredMessageMeta[] {
     }
   }
 
-  return messages.sort((a, b) => a.id.localeCompare(b.id))
+  return messages.sort((a, b) => {
+    const aTime = a.time?.created ?? 0
+    const bTime = b.time?.created ?? 0
+    if (aTime !== bTime) return aTime - bTime
+    return a.id.localeCompare(b.id)
+  })
 }
 
 export function readParts(messageID: string): StoredPart[] {
@@ -117,13 +122,9 @@ export function findEmptyMessages(sessionID: string): string[] {
   const messages = readMessages(sessionID)
   const emptyIds: string[] = []
 
-  for (let i = 0; i < messages.length; i++) {
-    const msg = messages[i]
+  for (const msg of messages) {
     if (msg.role !== "assistant") continue
 
-    const isLastMessage = i === messages.length - 1
-    if (isLastMessage) continue
-
     if (!messageHasContent(msg.id)) {
       emptyIds.push(msg.id)
     }
@@ -132,6 +133,18 @@ export function findEmptyMessages(sessionID: string): string[] {
   return emptyIds
 }
 
+export function findEmptyMessageByIndex(sessionID: string, targetIndex: number): string | null {
+  const messages = readMessages(sessionID)
+  
+  if (targetIndex < 0 || targetIndex >= messages.length) return null
+
+  const targetMsg = messages[targetIndex]
+  if (targetMsg.role !== "assistant") return null
+  if (messageHasContent(targetMsg.id)) return null
+
+  return targetMsg.id
+}
+
 export function findFirstEmptyMessage(sessionID: string): string | null {
   const emptyIds = findEmptyMessages(sessionID)
   return emptyIds.length > 0 ? emptyIds[0] : null