diff --git a/src/commands/onboard-non-interactive.ts b/src/commands/onboard-non-interactive.ts
index e8aecb888a0..e77a23f2b3f 100644
--- a/src/commands/onboard-non-interactive.ts
+++ b/src/commands/onboard-non-interactive.ts
@@ -83,6 +83,7 @@ async function runNonInteractiveMigrationImport(params: {
       await replaceConfigFile({
         nextConfig: config,
         ...(params.baseHash !== undefined ? { baseHash: params.baseHash } : {}),
+        writeOptions: { allowConfigSizeDrop: true },
       });
       logConfigUpdated(params.runtime);
       return config;
diff --git a/src/commands/onboard-non-interactive/local.ts b/src/commands/onboard-non-interactive/local.ts
index da522480d75..2a53ad7b07e 100644
--- a/src/commands/onboard-non-interactive/local.ts
+++ b/src/commands/onboard-non-interactive/local.ts
@@ -208,6 +208,7 @@ export async function runNonInteractiveLocalSetup(params: {
   await replaceConfigFile({
     nextConfig,
     ...(baseHash !== undefined ? { baseHash } : {}),
+    writeOptions: { allowConfigSizeDrop: true },
   });
   logConfigUpdated(runtime);
   await preparePostConfigBundledRuntimeDeps({ config: nextConfig, runtime });
diff --git a/src/commands/onboard-non-interactive/remote.ts b/src/commands/onboard-non-interactive/remote.ts
index 4a20f5cc3cd..ec3a662dd20 100644
--- a/src/commands/onboard-non-interactive/remote.ts
+++ b/src/commands/onboard-non-interactive/remote.ts
@@ -42,6 +42,7 @@ export async function runNonInteractiveRemoteSetup(params: {
   await replaceConfigFile({
     nextConfig,
     ...(baseHash !== undefined ? { baseHash } : {}),
+    writeOptions: { allowConfigSizeDrop: true },
   });
   logConfigUpdated(runtime);
 
diff --git a/src/wizard/setup.test.ts b/src/wizard/setup.test.ts
index e71573d5702..2bfbe840029 100644
--- a/src/wizard/setup.test.ts
+++ b/src/wizard/setup.test.ts
@@ -537,6 +537,7 @@ describe("runSetupWizard", () => {
             }),
           }),
         }),
+        writeOptions: expect.objectContaining({ allowConfigSizeDrop: true }),
       }),
     );
     expect(ensureWorkspaceAndSessions).toHaveBeenCalledWith(
diff --git a/src/wizard/setup.ts b/src/wizard/setup.ts
index 8913dbbdfaa..866ab27475d 100644
--- a/src/wizard/setup.ts
+++ b/src/wizard/setup.ts
@@ -61,7 +61,7 @@ async function writeWizardConfigFile(config: OpenClawConfig): Promise<OpenClawCo
     commit: async (nextConfig, writeOptions) => {
       await replaceConfigFile({
         nextConfig,
-        ...(writeOptions ? { writeOptions } : {}),
+        writeOptions: { ...writeOptions, allowConfigSizeDrop: true },
         afterWrite: { mode: "auto" },
       });
     },