diff --git a/packages/coding-agent/src/cursor.ts b/packages/coding-agent/src/cursor.ts
index 5865189c5..4bc29fb0c 100644
--- a/packages/coding-agent/src/cursor.ts
+++ b/packages/coding-agent/src/cursor.ts
@@ -93,6 +93,7 @@ async function executeTool(
 		result = buildToolErrorResult(message);
 		isError = true;
 	}
+	isError ||= result.isError === true;
 
 	const sanitizedFinalResult: AgentToolResult<unknown> = {
 		content: result.content.map(c => (c.type === "text" ? { ...c, text: sanitizeText(c.text) } : c)),
@@ -283,6 +284,7 @@ export class CursorExecHandlers implements ICursorExecHandlers {
 			result = buildToolErrorResult(message);
 			isError = true;
 		}
+		isError ||= result.isError === true;
 
 		// onUpdate may not fire for every chunk — flush any remaining output
 		// from the final result that wasn't already streamed.
diff --git a/packages/coding-agent/test/cursor-exec.test.ts b/packages/coding-agent/test/cursor-exec.test.ts
index fde7857f4..9dc1c49bb 100644
--- a/packages/coding-agent/test/cursor-exec.test.ts
+++ b/packages/coding-agent/test/cursor-exec.test.ts
@@ -2,10 +2,14 @@ import { afterEach, beforeEach, describe, expect, it } from "bun:test";
 import * as fs from "node:fs/promises";
 import * as os from "node:os";
 import * as path from "node:path";
+import { create } from "@bufbuild/protobuf";
+import type { AgentEvent, AgentTool } from "@oh-my-pi/pi-agent-core";
+import { ReadArgsSchema, ShellArgsSchema } from "@oh-my-pi/pi-catalog/discovery/cursor-gen/agent_pb";
 import { Settings } from "@oh-my-pi/pi-coding-agent/config/settings";
 import { CursorExecHandlers } from "@oh-my-pi/pi-coding-agent/cursor";
 import { GrepTool, type ToolSession } from "@oh-my-pi/pi-coding-agent/tools";
 import { removeWithRetries } from "@oh-my-pi/pi-utils";
+import { type } from "arktype";
 
 function createTestSession(cwd: string, overrides: Partial<ToolSession> = {}): ToolSession {
 	return {
@@ -65,3 +69,55 @@ describe("CursorExecHandlers.grep bridge", () => {
 		expect((sensitiveResult.details as { matchCount?: number } | undefined)?.matchCount).toBe(1);
 	});
 });
+
+describe("CursorExecHandlers error results", () => {
+	const rewrittenErrorTool = (name: string): AgentTool => ({
+		name,
+		label: name,
+		description: "returns a rewritten tool failure",
+		parameters: type({}),
+		execute: async () => ({
+			content: [{ type: "text", text: "Enriched recovery guidance" }],
+			details: { enriched: true },
+			isError: true,
+		}),
+	});
+
+	it("propagates returned isError through the standard exec bridge", async () => {
+		const events: AgentEvent[] = [];
+		const handlers = new CursorExecHandlers({
+			cwd: ".",
+			tools: new Map([["read", rewrittenErrorTool("read")]]),
+			emitEvent: event => events.push(event),
+		});
+
+		const result = await handlers.read(create(ReadArgsSchema, { toolCallId: "call-read", path: "ignored" }));
+		expect(result.isError).toBe(true);
+		expect(result.content).toEqual([{ type: "text", text: "Enriched recovery guidance" }]);
+		const end = events.find(event => event.type === "tool_execution_end");
+		expect(end?.isError).toBe(true);
+	});
+
+	it("propagates returned isError through the shell stream bridge", async () => {
+		const events: AgentEvent[] = [];
+		const stdout: string[] = [];
+		const handlers = new CursorExecHandlers({
+			cwd: ".",
+			tools: new Map([["bash", rewrittenErrorTool("bash")]]),
+			emitEvent: event => events.push(event),
+		});
+
+		const result = await handlers.shellStream(
+			create(ShellArgsSchema, { toolCallId: "call-shell", command: "ignored" }),
+			{
+				onStdout: data => stdout.push(data),
+				onStderr: () => {},
+			},
+		);
+		expect(result.isError).toBe(true);
+		expect(result.content).toEqual([{ type: "text", text: "Enriched recovery guidance" }]);
+		expect(stdout).toEqual(["Enriched recovery guidance"]);
+		const end = events.find(event => event.type === "tool_execution_end");
+		expect(end?.isError).toBe(true);
+	});
+});