fix(coding-agent/debug): Sanitized debug log rendering

- Sanitized debug log lines by stripping ANSI/control codes, replacing tabs, and truncating to terminal width.
- Added formatting helper and unit tests covering sanitization, tab handling, and truncation.

packages/coding-agent/CHANGELOG.md

@@ -9,6 +9,9 @@
 
 - Fixed `session.abort()` not clearing `promptInFlight` flag due to microtask ordering, which blocked subsequent prompts
 
+### Fixed
+- Sanitized debug log display to strip control codes, normalize tabs, and trim width
+
 ## [12.4.0] - 2026-02-14
 ### Changed
 
@@ -69,6 +72,7 @@
 - Improved error reporting in fetch tool to include HTTP status codes when URL fetching fails
 - Fixed fetch tool to preserve actual response metadata (finalUrl, contentType) instead of defaults when requests fail
 
+||||||| parent of a70a34c8b (fix(coding-agent/debug): Sanitized debug log rendering)
 ## [12.1.0] - 2026-02-13
 
 ### Added

packages/coding-agent/src/debug/index.ts

@@ -11,6 +11,7 @@ import { DynamicBorder } from "../modes/components/dynamic-border";
 import { getSelectListTheme, getSymbolTheme, theme } from "../modes/theme/theme";
 import type { InteractiveModeContext } from "../modes/types";
 import { openPath } from "../utils/open";
+import { formatDebugLogLine } from "./log-formatting";
 import { generateHeapSnapshotData, type ProfilerSession, startCpuProfile } from "./profiler";
 import { clearArtifactCache, createReportBundle, getArtifactCacheStats, getRecentLogs } from "./report-bundle";
 import { collectSystemInfo, formatSystemInfo } from "./system-info";
@@ -284,10 +285,12 @@ export class DebugSelectorComponent extends Container {
 			this.ctx.chatContainer.addChild(new Spacer(1));
 
 			// Display logs with dim styling
+			const maxWidth = Math.max(1, this.ctx.ui.terminal.columns - 2);
 			const lines = logs.split("\n").slice(-50);
 			for (const line of lines) {
-				if (line.trim()) {
-					this.ctx.chatContainer.addChild(new Text(theme.fg("dim", line), 1, 0));
+				const formatted = formatDebugLogLine(line, maxWidth);
+				if (formatted.trim()) {
+					this.ctx.chatContainer.addChild(new Text(theme.fg("dim", formatted), 1, 0));
 				}
 			}
 

packages/coding-agent/src/debug/log-formatting.ts

@@ -0,0 +1,9 @@
+import { sanitizeText } from "@oh-my-pi/pi-utils";
+import { replaceTabs, truncateToWidth } from "../tools/render-utils";
+
+export function formatDebugLogLine(line: string, maxWidth: number): string {
+	const sanitized = sanitizeText(line);
+	const normalized = replaceTabs(sanitized);
+	const width = Math.max(1, maxWidth);
+	return truncateToWidth(normalized, width);
+}

packages/coding-agent/test/debug/log-formatting.test.ts

@@ -0,0 +1,29 @@
+import { describe, expect, it } from "bun:test";
+import { formatDebugLogLine } from "../../src/debug/log-formatting";
+
+describe("formatDebugLogLine", () => {
+	it("strips ANSI codes and carriage returns", () => {
+		const input = "\u001b[31merror\r\u001b[0m";
+		const result = formatDebugLogLine(input, 80);
+		expect(result).toBe("error");
+	});
+
+	it("replaces tabs with spaces", () => {
+		const input = "col1\tcol2";
+		const result = formatDebugLogLine(input, 80);
+		expect(result).toBe("col1   col2");
+	});
+
+	it("removes unsafe control characters", () => {
+		const input = "ok\u0007bad";
+		const result = formatDebugLogLine(input, 80);
+		expect(result).toBe("okbad");
+	});
+
+	it("truncates long lines", () => {
+		const input = "0123456789ABCDEFGHIJ";
+		const result = formatDebugLogLine(input, 10);
+		expect(Bun.stringWidth(result)).toBeLessThanOrEqual(10);
+		expect(result.startsWith("012345")).toBe(true);
+	});
+});