From ad10d3a1268d41596c508c8b88b3be9a86edfcea Mon Sep 17 00:00:00 2001
From: Aiden Cline <63023139+rekram1-node@users.noreply.github.com>
Date: Wed, 6 Aug 2025 05:16:43 -0500
Subject: [PATCH] fix: handle undefined agent in task tool (#1642)

---
 packages/opencode/src/tool/task.ts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/packages/opencode/src/tool/task.ts b/packages/opencode/src/tool/task.ts
index ceec9c1a..0ae0ef79 100644
--- a/packages/opencode/src/tool/task.ts
+++ b/packages/opencode/src/tool/task.ts
@@ -22,6 +22,7 @@ export const TaskTool = Tool.define("task", async () => {
       const msg = await Session.getMessage(ctx.sessionID, ctx.messageID)
       if (msg.info.role !== "assistant") throw new Error("Not an assistant message")
       const agent = await Agent.get(params.subagent_type)
+      if (!agent) throw new Error(`Unknown agent type: ${params.subagent_type} is not a valid agent type`)
       const messageID = Identifier.ascending("message")
       const parts: Record<string, MessageV2.ToolPart> = {}
       const unsub = Bus.subscribe(MessageV2.Event.PartUpdated, async (evt) => {