diff --git a/packages/opencode/src/acp/agent.ts b/packages/opencode/src/acp/agent.ts
index 77aea216b..ab9b08f38 100644
--- a/packages/opencode/src/acp/agent.ts
+++ b/packages/opencode/src/acp/agent.ts
@@ -34,6 +34,18 @@ import type { OpencodeClient } from "@opencode-ai/sdk"
 export namespace ACP {
   const log = Log.create({ service: "acp-agent" })
 
+  async function getDefaultAgent(): Promise<string> {
+    const cfg = await Config.get()
+    const defaultAgent = cfg.default_agent
+
+    if (defaultAgent) {
+      return defaultAgent
+    }
+
+    // Fallback to build agent
+    return "build"
+  }
+
   export async function init({ sdk }: { sdk: OpencodeClient }) {
     const model = await defaultModel({ sdk })
     return {
@@ -475,7 +487,7 @@ export namespace ACP {
           description: agent.description,
         }))
 
-      const defaultAgentName = await Agent.getDefault()
+      const defaultAgentName = await getDefaultAgent()
       const currentModeId = availableModes.find((m) => m.name === defaultAgentName)?.id ?? availableModes[0].id
 
       const mcpServers: Record<string, Config.Mcp> = {}
@@ -578,7 +590,7 @@ export namespace ACP {
       if (!current) {
         this.sessionManager.setModel(session.id, model)
       }
-      const agent = session.modeId ?? (await Agent.getDefault())
+      const agent = session.modeId ?? (await getDefaultAgent())
 
       const parts: Array<
         { type: "text"; text: string } | { type: "file"; url: string; filename: string; mime: string }
diff --git a/packages/opencode/src/cli/cmd/run.ts b/packages/opencode/src/cli/cmd/run.ts
index b5e94f6ef..eedf4f323 100644
--- a/packages/opencode/src/cli/cmd/run.ts
+++ b/packages/opencode/src/cli/cmd/run.ts
@@ -10,6 +10,7 @@ import { select } from "@clack/prompts"
 import { createOpencodeClient, type OpencodeClient } from "@opencode-ai/sdk"
 import { Server } from "../../server/server"
 import { Provider } from "../../provider/provider"
+import { Agent } from "../../agent/agent"
 
 const TOOL: Record<string, [string, string]> = {
   todowrite: ["Todo", UI.Style.TEXT_WARNING_BOLD],
diff --git a/packages/opencode/src/session/compaction.ts b/packages/opencode/src/session/compaction.ts
index 9b1745e92..dddc5a08b 100644
--- a/packages/opencode/src/session/compaction.ts
+++ b/packages/opencode/src/session/compaction.ts
@@ -15,6 +15,7 @@ import { Log } from "../util/log"
 import { ProviderTransform } from "@/provider/transform"
 import { SessionProcessor } from "./processor"
 import { fn } from "@/util/fn"
+import { Agent } from "../agent/agent"
 
 export namespace SessionCompaction {
   const log = Log.create({ service: "session.compaction" })
diff --git a/packages/opencode/tsconfig.json b/packages/opencode/tsconfig.json
index 9067d84fd..ab333245f 100644
--- a/packages/opencode/tsconfig.json
+++ b/packages/opencode/tsconfig.json
@@ -1,12 +1,13 @@
 {
   "$schema": "https://json.schemastore.org/tsconfig",
-  "extends": "@tsconfig/bun/tsconfig.json",
   "compilerOptions": {
     "jsx": "preserve",
     "jsxImportSource": "@opentui/solid",
     "lib": ["ESNext", "DOM", "DOM.Iterable"],
     "types": [],
     "noUncheckedIndexedAccess": false,
+    "module": "ESNext",
+    "moduleResolution": "bundler",
     "customConditions": ["browser"],
     "paths": {
       "@/*": ["./src/*"],