diff --git a/src/core/codex-adapter.ts b/src/core/codex-adapter.ts
index f498996..29e3a23 100644
--- a/src/core/codex-adapter.ts
+++ b/src/core/codex-adapter.ts
@@ -24,13 +24,13 @@ import { scanTarget, type PreparedScanPlan } from './scan-plan.ts';
 import { userMessage } from './errors.ts';
 import { savedScan } from './partial-results.ts';
 import type { Finding, ScanState } from '../types.js';
+import { loadSdk } from './sdk.ts';
 
 export type SecurityClient = Pick<CodexSecurity, 'run' | 'close'>;
 export type SecurityFactory = (
   config: CodexSecurityConfig,
 ) => SecurityClient | Promise<SecurityClient>;
-const realClient: SecurityFactory = async (config) =>
-  new (await import('@openai/codex-security')).CodexSecurity(config);
+const realClient: SecurityFactory = async (config) => new (await loadSdk()).CodexSecurity(config);
 function initial(repository: string, revision = 0, instanceId = ''): ScanState {
   return {
     telemetry: emptyTelemetry(),
diff --git a/src/core/scan-plan.ts b/src/core/scan-plan.ts
index 275506a..aefec1b 100644
--- a/src/core/scan-plan.ts
+++ b/src/core/scan-plan.ts
@@ -12,6 +12,7 @@ import type {
 import { codexHome, loadSettings } from './settings.ts';
 import { SecurityInputError } from './errors.ts';
 import { storedState } from './sign-in.ts';
+import { loadSdk } from './sdk.ts';
 
 export interface ScanInputs {
   mode?: 'standard' | 'deep';
@@ -97,7 +98,7 @@ function parseInputs(value: unknown): ScanInputs {
 /** The SDK target for a plan: the whole repository, paths, or a diff. */
 export async function scanTarget(input: Pick<ScanInputs, 'scopePaths' | 'changes'>) {
   if (input.changes) {
-    const { DiffTarget } = await import('@openai/codex-security');
+    const { DiffTarget } = await loadSdk();
     return input.changes === 'uncommitted'
       ? DiffTarget.workingTree()
       : DiffTarget.refs({ base: input.changes });
@@ -141,7 +142,7 @@ export async function withSdk<T>(
   codexOverrides: JsonObject,
   use: (client: CodexSecurity, sdk: typeof import('@openai/codex-security')) => Promise<T>,
 ): Promise<T> {
-  const sdk = await import('@openai/codex-security');
+  const sdk = await loadSdk();
   const client = new sdk.CodexSecurity({ codexOverrides });
   try {
     return await use(client, sdk);
diff --git a/src/core/sdk.ts b/src/core/sdk.ts
new file mode 100644
index 0000000..b495f4f
--- /dev/null
+++ b/src/core/sdk.ts
@@ -0,0 +1,28 @@
+import { join } from 'node:path';
+import { pathToFileURL } from 'node:url';
+
+let ready: Promise<typeof import('@openai/codex-security')> | undefined;
+
+/**
+ * The SDK, with its bundled helper module already loaded.
+ *
+ * On load the helper compares `process.argv[1]` with its own path to see whether it is the main
+ * script. Inside OpenCode's compiled binary that argument is a virtual path that exists but
+ * cannot be resolved, so the load throws, and the SDK reports it as a scan that "completed
+ * without required artifacts". Loading the helper once with the argument blanked avoids that;
+ * later imports reuse the loaded module.
+ */
+export function loadSdk() {
+  return (ready ??= (async () => {
+    const sdk = await import('@openai/codex-security');
+    const helper = pathToFileURL(join(await sdk.bundledPluginRoot(), 'mcp/helpers.mjs')).href;
+    const invoked = process.argv[1];
+    process.argv[1] = '';
+    try {
+      await import(helper);
+    } finally {
+      process.argv[1] = invoked!;
+    }
+    return sdk;
+  })());
+}
diff --git a/src/core/security-operations.ts b/src/core/security-operations.ts
index 31da381..a6d84e6 100644
--- a/src/core/security-operations.ts
+++ b/src/core/security-operations.ts
@@ -23,6 +23,7 @@ import {
   type PatchWorkspace,
   type PatchWorkspaceFactory,
 } from './patch-workspace.ts';
+import { loadSdk } from './sdk.ts';
 
 export type SecurityOperationKind = 'policy' | 'validation' | 'fix';
 export type SecurityOperationStatus =
@@ -131,7 +132,7 @@ type Entry = {
   };
 };
 const realClient: SecurityOperationsFactory = async (config) =>
-  new (await import('@openai/codex-security')).CodexSecurity(config);
+  new (await loadSdk()).CodexSecurity(config);
 const active = (state: SecurityOperationState) =>
   state.status === 'running' || state.status === 'awaiting_answers';
 const textLimit = 48_000;
@@ -346,7 +347,7 @@ export class SecurityOperationsService {
         // Computed in Node with no model call. The SDK refuses if SECURITY.md changed since the
         // draft read it; the draft has been paid for, so return it without a diff instead.
         const diff = replacesExisting
-          ? await import('@openai/codex-security')
+          ? await loadSdk()
               .then((sdk) => sdk.securityPolicyDiff(result, undefined, signal))
               .catch(() => undefined)
           : undefined;
diff --git a/src/core/sign-in.ts b/src/core/sign-in.ts
index 558c0d0..dcc12cc 100644
--- a/src/core/sign-in.ts
+++ b/src/core/sign-in.ts
@@ -3,6 +3,7 @@ import { join } from 'node:path';
 import type { CodexSecurity, CodexSecurityConfig } from '@openai/codex-security';
 import { userMessage } from './errors.ts';
 import { codexHome, loadSettings, stateDirectory } from './settings.ts';
+import { loadSdk } from './sdk.ts';
 
 /**
  * Whether Codex Security has a ChatGPT sign-in of its own. Only relevant when the route uses
@@ -41,8 +42,7 @@ export class SignIn {
   #pending?: { url: string; code?: string; cancel(): void };
   #error?: string;
   constructor(
-    createClient: LoginFactory = async (config) =>
-      new (await import('@openai/codex-security')).CodexSecurity(config),
+    createClient: LoginFactory = async (config) => new (await loadSdk()).CodexSecurity(config),
   ) {
     this.#factory = createClient;
   }
diff --git a/tests/sdk.test.mjs b/tests/sdk.test.mjs
new file mode 100644
index 0000000..4c2fcc6
--- /dev/null
+++ b/tests/sdk.test.mjs
@@ -0,0 +1,17 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { loadSdk } from '../src/core/sdk.ts';
+
+test('the SDK helper loads even when the host reports an unresolvable main script', async () => {
+  const invoked = process.argv[1];
+  // What OpenCode's compiled binary reports: a path that cannot be resolved.
+  process.argv[1] = '/$bunfs/root/opencode';
+  try {
+    const sdk = await loadSdk();
+    assert.equal(typeof sdk.CodexSecurity, 'function');
+    assert.equal(process.argv[1], '/$bunfs/root/opencode');
+    assert.equal(await loadSdk(), sdk);
+  } finally {
+    process.argv[1] = invoked;
+  }
+});