diff --git a/apps/pi-extension/index.ts b/apps/pi-extension/index.ts
index d2524aba7..6b2bbc80a 100644
--- a/apps/pi-extension/index.ts
+++ b/apps/pi-extension/index.ts
@@ -68,6 +68,7 @@ import {
 import {
 	applyPhaseTools,
 	isPlanWritePathAllowed,
+	isPlannotatorSubmitDevicePath,
 	PLAN_MARK_DONE_TOOL,
 	PLAN_SUBMIT_TOOL,
 	releasePhaseTools,
@@ -1464,6 +1465,7 @@ export default function plannotator(pi: ExtensionAPI): void {
 		if (event.toolName !== "write" && event.toolName !== "edit") return;
 
 		const inputPath = event.input.path as string;
+		if (isPlannotatorSubmitDevicePath(inputPath)) return;
 		if (!isPlanWritePathAllowed(inputPath, ctx.cwd)) {
 			const verb = event.toolName === "write" ? "writes" : "edits";
 			return {
diff --git a/apps/pi-extension/tool-scope.test.ts b/apps/pi-extension/tool-scope.test.ts
index 83ad3c3b3..86a9280db 100644
--- a/apps/pi-extension/tool-scope.test.ts
+++ b/apps/pi-extension/tool-scope.test.ts
@@ -2,7 +2,9 @@ import { describe, expect, test } from "bun:test";
 import {
 	applyPhaseTools,
 	isPlanWritePathAllowed,
+	isPlannotatorSubmitDevicePath,
 	PLAN_MARK_DONE_TOOL,
+	PLAN_SUBMIT_DEVICE_URI,
 	PLAN_SUBMIT_TOOL,
 	releasePhaseTools,
 	stripPlanningOnlyTools,
@@ -87,3 +89,55 @@ describe("plan write path gate", () => {
 		expect(isPlanWritePathAllowed("notes.MdX", cwd)).toBe(true);
 	});
 });
+
+describe("plannotator submit device path gate", () => {
+	test("recognizes the exact submit device URI", () => {
+		expect(isPlannotatorSubmitDevicePath("xd://plannotator_submit_plan")).toBe(true);
+		expect(isPlannotatorSubmitDevicePath(PLAN_SUBMIT_DEVICE_URI)).toBe(true);
+	});
+
+	test("rejects lookalikes: suffix, subpath, or wrong case", () => {
+		// Suffix
+		expect(isPlannotatorSubmitDevicePath("xd://plannotator_submit_plan2")).toBe(false);
+		expect(isPlannotatorSubmitDevicePath("xd://plannotator_submit_plans")).toBe(false);
+		expect(isPlannotatorSubmitDevicePath("xd://plannotator_submit_plan_extra")).toBe(false);
+		// Subpath
+		expect(isPlannotatorSubmitDevicePath("xd://plannotator_submit_plan/")).toBe(false);
+		expect(isPlannotatorSubmitDevicePath("xd://plannotator_submit_plan/extra")).toBe(false);
+		expect(isPlannotatorSubmitDevicePath("xd://plannotator_submit_plan/sub/path")).toBe(false);
+		// Wrong scheme case
+		expect(isPlannotatorSubmitDevicePath("XD://plannotator_submit_plan")).toBe(false);
+		expect(isPlannotatorSubmitDevicePath("Xd://plannotator_submit_plan")).toBe(false);
+		// Wrong tool name case
+		expect(isPlannotatorSubmitDevicePath("xd://PLANNOTATOR_SUBMIT_PLAN")).toBe(false);
+		expect(isPlannotatorSubmitDevicePath("xd://Plannotator_Submit_Plan")).toBe(false);
+		// Surrounding whitespace
+		expect(isPlannotatorSubmitDevicePath(" xd://plannotator_submit_plan")).toBe(false);
+		expect(isPlannotatorSubmitDevicePath("xd://plannotator_submit_plan ")).toBe(false);
+	});
+
+	test("rejects other device URIs", () => {
+		expect(isPlannotatorSubmitDevicePath("xd://report_issue")).toBe(false);
+		expect(isPlannotatorSubmitDevicePath("xd://plannotator_mark_done")).toBe(false);
+		expect(isPlannotatorSubmitDevicePath("xd://eval")).toBe(false);
+		expect(isPlannotatorSubmitDevicePath("xd://bash")).toBe(false);
+		expect(isPlannotatorSubmitDevicePath("xd://browse")).toBe(false);
+	});
+
+	test("rejects non-string and empty inputs", () => {
+		expect(isPlannotatorSubmitDevicePath(undefined)).toBe(false);
+		expect(isPlannotatorSubmitDevicePath(null)).toBe(false);
+		expect(isPlannotatorSubmitDevicePath(123)).toBe(false);
+		expect(isPlannotatorSubmitDevicePath({})).toBe(false);
+		expect(isPlannotatorSubmitDevicePath([])).toBe(false);
+		expect(isPlannotatorSubmitDevicePath(true)).toBe(false);
+		expect(isPlannotatorSubmitDevicePath("")).toBe(false);
+	});
+
+	test("isPlanWritePathAllowed still rejects device URIs as plan file paths", () => {
+		const cwd = "/r";
+		expect(isPlanWritePathAllowed("xd://plannotator_submit_plan", cwd)).toBe(false);
+		expect(isPlanWritePathAllowed(PLAN_SUBMIT_DEVICE_URI, cwd)).toBe(false);
+		expect(isPlanWritePathAllowed("xd://report_issue", cwd)).toBe(false);
+	});
+});
diff --git a/apps/pi-extension/tool-scope.ts b/apps/pi-extension/tool-scope.ts
index 2872cb98f..523e8d28f 100644
--- a/apps/pi-extension/tool-scope.ts
+++ b/apps/pi-extension/tool-scope.ts
@@ -3,6 +3,11 @@ import { extname, isAbsolute, relative, resolve } from "node:path";
 export type Phase = "idle" | "planning" | "executing";
 
 export const PLAN_SUBMIT_TOOL = "plannotator_submit_plan";
+export const PLAN_SUBMIT_DEVICE_URI = `xd://${PLAN_SUBMIT_TOOL}` as const;
+
+export function isPlannotatorSubmitDevicePath(input: unknown): boolean {
+	return typeof input === "string" && input === PLAN_SUBMIT_DEVICE_URI;
+}
 export const PLAN_MARK_DONE_TOOL = "plannotator_mark_done";
 
 const ALLOWED_PLAN_EXTENSIONS = new Set<string>([".md", ".mdx"]);