From 7ebafe226739f94be46e420ef5c4734ac48de47d Mon Sep 17 00:00:00 2001
From: YeonGyu-Kim <code.yeon.gyu@gmail.com>
Date: Tue, 3 Feb 2026 12:11:49 +0900
Subject: [PATCH] refactor(config-handler): separate plan prompt into dedicated
 configuration (#1413)

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
---
 src/plugin-handlers/config-handler.test.ts |  4 +++-
 src/plugin-handlers/config-handler.ts      | 18 ++++++++++--------
 2 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/src/plugin-handlers/config-handler.test.ts b/src/plugin-handlers/config-handler.test.ts
index db855263..7c095101 100644
--- a/src/plugin-handlers/config-handler.test.ts
+++ b/src/plugin-handlers/config-handler.test.ts
@@ -176,10 +176,12 @@ describe("Plan agent demote behavior", () => {
     await handler(config)
 
     // then
-    const agents = config.agent as Record<string, { mode?: string; name?: string }>
+    const agents = config.agent as Record<string, { mode?: string; name?: string; prompt?: string }>
     expect(agents.plan).toBeDefined()
     expect(agents.plan.mode).toBe("subagent")
     expect(agents.plan.name).toBe("plan")
+    expect(agents.plan.prompt).toBe("original plan prompt")
+    expect(agents.plan.prompt).not.toBe(agents.prometheus?.prompt)
   })
 
   test("prometheus should have mode 'all' to be callable via delegate_task", async () => {
diff --git a/src/plugin-handlers/config-handler.ts b/src/plugin-handlers/config-handler.ts
index 19c6dd02..15dc7732 100644
--- a/src/plugin-handlers/config-handler.ts
+++ b/src/plugin-handlers/config-handler.ts
@@ -210,6 +210,12 @@ export function createConfigHandler(deps: ConfigHandlerDeps) {
     };
     const configAgent = config.agent as AgentConfig | undefined;
 
+    const { name: _planName, mode: _planMode, ...planConfigWithoutName } =
+      configAgent?.plan ?? {};
+    const planPrompt = (migrateAgentConfig(
+      planConfigWithoutName as Record<string, unknown>
+    ) as { prompt?: string }).prompt;
+
     if (isSisyphusEnabled && builtinAgents.sisyphus) {
       (config as { default_agent?: string }).default_agent = "sisyphus";
 
@@ -241,11 +247,6 @@ export function createConfigHandler(deps: ConfigHandlerDeps) {
       }
 
       if (plannerEnabled) {
-        const { name: _planName, mode: _planMode, ...planConfigWithoutName } =
-          configAgent?.plan ?? {};
-        const migratedPlanConfig = migrateAgentConfig(
-          planConfigWithoutName as Record<string, unknown>
-        );
         const prometheusOverride =
           pluginConfig.agents?.["prometheus"] as
             | (Record<string, unknown> & {
@@ -362,10 +363,11 @@ export function createConfigHandler(deps: ConfigHandlerDeps) {
         : {};
 
       const planDemoteConfig = replacePlan && agentConfig["prometheus"]
-        ? { 
+        ? {
             ...agentConfig["prometheus"],
-            name: "plan", 
-            mode: "subagent" as const 
+            name: "plan",
+            mode: "subagent" as const,
+            ...(planPrompt ? { prompt: planPrompt } : {}),
           }
         : undefined;