refactor(llm): share user message coalescing

Co-authored-by: kiloconnect[bot] <240665456+kiloconnect[bot]@users.noreply.github.com>

packages/llm/src/protocols/anthropic-messages.ts

@@ -415,10 +415,7 @@ const lowerMessages = Effect.fn("AnthropicMessages.lowerMessages")(function* (
       }
       const part = yield* ProviderShared.wrappedSystemUpdate("Anthropic Messages", message)
       const block = { type: "text" as const, text: part.text, cache_control: cacheControl(breakpoints, part.cache) }
-      const previous = messages.at(-1)
-      if (previous?.role === "user")
-        messages[messages.length - 1] = { role: "user", content: [...previous.content, block] }
-      else messages.push({ role: "user", content: [block] })
+      ProviderShared.appendUserMessage(messages, { role: "user", content: [block] }) // kilocode_change
       continue
     }
 
@@ -435,10 +432,7 @@ const lowerMessages = Effect.fn("AnthropicMessages.lowerMessages")(function* (
         }
         return yield* ProviderShared.unsupportedContent("Anthropic Messages", "user", ["text", "media"])
       }
-      const previous = messages.at(-1) // kilocode_change
-      if (previous?.role === "user") // kilocode_change
-        messages[messages.length - 1] = { role: "user", content: [...previous.content, ...content] } // kilocode_change
-      else messages.push({ role: "user", content }) // kilocode_change
+      ProviderShared.appendUserMessage(messages, { role: "user", content }) // kilocode_change
       continue
     }
 
@@ -485,10 +479,7 @@ const lowerMessages = Effect.fn("AnthropicMessages.lowerMessages")(function* (
         cache_control: cacheControl(breakpoints, part.cache),
       })
     }
-    const previous = messages.at(-1) // kilocode_change
-    if (previous?.role === "user") // kilocode_change
-      messages[messages.length - 1] = { role: "user", content: [...previous.content, ...content] } // kilocode_change
-    else messages.push({ role: "user", content }) // kilocode_change
+    ProviderShared.appendUserMessage(messages, { role: "user", content }) // kilocode_change
   }
 
   return messages

packages/llm/src/protocols/bedrock-converse.ts

@@ -309,10 +309,7 @@ const lowerMessages = Effect.fn("BedrockConverse.lowerMessages")(function* (
     if (message.role === "system") {
       const part = yield* ProviderShared.wrappedSystemUpdate("Bedrock Converse", message)
       const content = textWithCache(breakpoints, part.text, part.cache)
-      const previous = messages.at(-1)
-      if (previous?.role === "user")
-        messages[messages.length - 1] = { role: "user", content: [...previous.content, ...content] }
-      else messages.push({ role: "user", content })
+      ProviderShared.appendUserMessage(messages, { role: "user", content }) // kilocode_change
       continue
     }
 
@@ -330,10 +327,7 @@ const lowerMessages = Effect.fn("BedrockConverse.lowerMessages")(function* (
           continue
         }
       }
-      const previous = messages.at(-1) // kilocode_change
-      if (previous?.role === "user") // kilocode_change
-        messages[messages.length - 1] = { role: "user", content: [...previous.content, ...content] } // kilocode_change
-      else messages.push({ role: "user", content }) // kilocode_change
+      ProviderShared.appendUserMessage(messages, { role: "user", content }) // kilocode_change
       continue
     }
 
@@ -375,10 +369,7 @@ const lowerMessages = Effect.fn("BedrockConverse.lowerMessages")(function* (
       const cachePoint = BedrockCache.block(breakpoints, part.cache)
       if (cachePoint) content.push(cachePoint)
     }
-    const previous = messages.at(-1) // kilocode_change
-    if (previous?.role === "user") // kilocode_change
-      messages[messages.length - 1] = { role: "user", content: [...previous.content, ...content] } // kilocode_change
-    else messages.push({ role: "user", content }) // kilocode_change
+    ProviderShared.appendUserMessage(messages, { role: "user", content }) // kilocode_change
   }
 
   return messages

packages/llm/src/protocols/gemini.ts

@@ -208,10 +208,7 @@ const lowerMessages = Effect.fn("Gemini.lowerMessages")(function* (request: LLMR
   for (const message of request.messages) {
     if (message.role === "system") {
       const part = yield* ProviderShared.wrappedSystemUpdate("Gemini", message)
-      const previous = contents.at(-1)
-      if (previous?.role === "user")
-        contents[contents.length - 1] = { role: "user", parts: [...previous.parts, { text: part.text }] }
-      else contents.push({ role: "user", parts: [{ text: part.text }] })
+      ProviderShared.appendUserMessage(contents, { role: "user", parts: [{ text: part.text }] }) // kilocode_change
       continue
     }
 
@@ -222,10 +219,7 @@ const lowerMessages = Effect.fn("Gemini.lowerMessages")(function* (request: LLMR
           return yield* ProviderShared.unsupportedContent("Gemini", "user", ["text", "media"])
         parts.push(yield* lowerUserPart(part))
       }
-      const previous = contents.at(-1) // kilocode_change
-      if (previous?.role === "user") // kilocode_change
-        contents[contents.length - 1] = { role: "user", parts: [...previous.parts, ...parts] } // kilocode_change
-      else contents.push({ role: "user", parts }) // kilocode_change
+      ProviderShared.appendUserMessage(contents, { role: "user", parts }) // kilocode_change
       continue
     }
 
@@ -284,10 +278,7 @@ const lowerMessages = Effect.fn("Gemini.lowerMessages")(function* (request: LLMR
         parts.push({ inlineData: { mimeType: media.mime, data: media.base64 } })
       }
     }
-    const previous = contents.at(-1) // kilocode_change
-    if (previous?.role === "user") // kilocode_change
-      contents[contents.length - 1] = { role: "user", parts: [...previous.parts, ...parts] } // kilocode_change
-    else contents.push({ role: "user", parts }) // kilocode_change
+    ProviderShared.appendUserMessage(contents, { role: "user", parts }) // kilocode_change
   }
 
   return contents

packages/llm/src/protocols/shared.ts

@@ -108,6 +108,30 @@ export const parseJson = (route: string, input: string, message: string) =>
  */
 export const joinText = (parts: ReadonlyArray<{ readonly text: string }>) => parts.map((part) => part.text).join("\n")
 
+// kilocode_change start - preserve provider role alternation when tool results lower to user messages
+type UserMessage =
+  | { readonly role: "user"; readonly content: ReadonlyArray<unknown> }
+  | { readonly role: "user"; readonly parts: ReadonlyArray<unknown> }
+
+export const appendUserMessage = <Message extends { readonly role: string }, User extends Message & UserMessage>(
+  messages: Message[],
+  message: User,
+) => {
+  const previous = messages.at(-1)
+  if (previous?.role !== "user") {
+    messages.push(message)
+    return
+  }
+  if ("content" in message) {
+    const content = (previous as { readonly content: ReadonlyArray<unknown> }).content
+    messages[messages.length - 1] = { ...message, content: [...content, ...message.content] }
+    return
+  }
+  const parts = (previous as { readonly parts: ReadonlyArray<unknown> }).parts
+  messages[messages.length - 1] = { ...message, parts: [...parts, ...message.parts] }
+}
+// kilocode_change end
+
 const escapeSystemUpdateText = (text: string) =>
   text.replaceAll("&", "&amp;").replaceAll("<", "&lt;").replaceAll(">", "&gt;")