feat: AI SDK v6 support (#18433)

packages/opencode/src/session/message-v2.ts

@@ -573,11 +573,11 @@ export namespace MessageV2 {
     }))
   }
 
-  export function toModelMessages(
+  export async function toModelMessages(
     input: WithParts[],
     model: Provider.Model,
     options?: { stripMedia?: boolean },
-  ): ModelMessage[] {
+  ): Promise<ModelMessage[]> {
     const result: UIMessage[] = []
     const toolNames = new Set<string>()
     // Track media from tool results that need to be injected as user messages
@@ -601,7 +601,8 @@ export namespace MessageV2 {
       return false
     })()
 
-    const toModelOutput = (output: unknown) => {
+    const toModelOutput = (options: { toolCallId: string; input: unknown; output: unknown }) => {
+      const output = options.output
       if (typeof output === "string") {
         return { type: "text", value: output }
       }
@@ -799,7 +800,7 @@ export namespace MessageV2 {
 
     const tools = Object.fromEntries(Array.from(toolNames).map((toolName) => [toolName, { toModelOutput }]))
 
-    return convertToModelMessages(
+    return await convertToModelMessages(
       result.filter((msg) => msg.parts.some((part) => part.type !== "step-start")),
       {
         //@ts-expect-error (convertToModelMessages expects a ToolSet but only actually needs tools[name]?.toModelOutput)
@@ -871,7 +872,13 @@ export namespace MessageV2 {
       db.select().from(PartTable).where(eq(PartTable.message_id, message_id)).orderBy(PartTable.id).all(),
     )
     return rows.map(
-      (row) => ({ ...row.data, id: row.id, sessionID: row.session_id, messageID: row.message_id }) as MessageV2.Part,
+      (row) =>
+        ({
+          ...row.data,
+          id: row.id,
+          sessionID: row.session_id,
+          messageID: row.message_id,
+        }) as MessageV2.Part,
     )
   })