diff --git a/packages/logger/src/logger.js b/packages/logger/src/logger.js
index 54c212455..63b884b2b 100644
--- a/packages/logger/src/logger.js
+++ b/packages/logger/src/logger.js
@@ -1,6 +1,6 @@
 import { colors } from './utils.js';
 
-const URL_REGEXP = /\bhttps?:\/\/[^\s/$.?#].[^\s]*\b/i;
+const URL_REGEXP = /https?:\/\/[-a-zA-Z0-9@:%._+~#=]{2,256}\.[a-z]{2,4}\b([-a-zA-Z0-9@:;%_+.~#?&//=[\]]*)/i;
 const LOG_LEVELS = { debug: 0, info: 1, warn: 2, error: 3 };
 
 // A PercyLogger instance retains logs in-memory for quick lookups while also writing log
@@ -95,6 +95,7 @@ export class PercyLogger {
 
   // Formats messages before they are logged to stdio
   format(debug, level, message, elapsed) {
+    let color = (n, m) => this.isTTY ? colors[n](m) : m;
     let label = 'percy';
     let suffix = '';
 
@@ -112,37 +113,43 @@ export class PercyLogger {
 
       // include elapsed time since last log
       if (elapsed != null) {
-        suffix = ' ' + colors.grey(`(${elapsed}ms)`);
+        suffix = ' ' + color('grey', `(${elapsed}ms)`);
       }
     }
 
-    label = colors.magenta(label);
+    // add colors
+    label = color('magenta', label);
 
     if (level === 'error') {
       // red errors
-      message = colors.red(message);
+      message = color('red', message);
     } else if (level === 'warn') {
       // yellow warnings
-      message = colors.yellow(message);
+      message = color('yellow', message);
     } else if (level === 'info' || level === 'debug') {
       // blue info and debug URLs
-      message = message.replace(URL_REGEXP, colors.blue('$&'));
+      message = message.replace(URL_REGEXP, color('blue', '$&'));
     }
 
     return `[${label}] ${message}${suffix}`;
   }
 
+  // True if stdout is a TTY interface
+  get isTTY() {
+    return !!this.constructor.stdout.isTTY;
+  }
+
   // Replaces the current line with a log message
   progress(debug, message, persist) {
     if (!this.shouldLog(debug, 'info')) return;
     let { stdout } = this.constructor;
 
-    if (stdout.isTTY || !this._progress) {
+    if (this.isTTY || !this._progress) {
       message &&= this.format(debug, message);
-      if (stdout.isTTY) stdout.cursorTo(0);
+      if (this.isTTY) stdout.cursorTo(0);
       else message &&= message + '\n';
       if (message) stdout.write(message);
-      if (stdout.isTTY) stdout.clearLine(1);
+      if (this.isTTY) stdout.clearLine(1);
     }
 
     this._progress = !!message && { message, persist };
@@ -174,29 +181,32 @@ export class PercyLogger {
     // save log entries
     let timestamp = Date.now();
     message = err ? (message.stack || err) : message.toString();
-    let entry = { debug, level, message, meta, timestamp };
+    let entry = { debug, level, message, meta, timestamp, error: !!err };
     this.messages.add(entry);
 
     // maybe write the message to stdio
     if (this.shouldLog(debug, level)) {
+      // unless the loglevel is debug, write shorter error messages
       if (err && this.level !== 'debug') message = err;
-      let elapsed = timestamp - (this.lastlog || timestamp);
-      this.write(level, this.format(debug, err ? 'error' : level, message, elapsed));
+      this.write({ ...entry, message });
       this.lastlog = timestamp;
     }
   }
 
-  // Writes a message to stdio based on the loglevel
-  write(level, message) {
+  // Writes a log entry to stdio based on the loglevel
+  write({ debug, level, message, timestamp, error }) {
+    let elapsed = timestamp - (this.lastlog || timestamp);
+    let msg = this.format(debug, error ? 'error' : level, message, elapsed);
+    let progress = this.isTTY && this._progress;
     let { stdout, stderr } = this.constructor;
-    let progress = stdout.isTTY && this._progress;
 
+    // clear any logged progress
     if (progress) {
       stdout.cursorTo(0);
       stdout.clearLine(0);
     }
 
-    (level === 'info' ? stdout : stderr).write(message + '\n');
+    (level === 'info' ? stdout : stderr).write(msg + '\n');
     if (!this._progress?.persist) delete this._progress;
     else if (progress) stdout.write(progress.message);
   }
diff --git a/packages/logger/test/logger.test.js b/packages/logger/test/logger.test.js
index 34240fd1a..50c504f8b 100644
--- a/packages/logger/test/logger.test.js
+++ b/packages/logger/test/logger.test.js
@@ -6,7 +6,7 @@ describe('logger', () => {
   let log, inst;
 
   beforeEach(async () => {
-    await helpers.mock({ ansi: true });
+    await helpers.mock({ ansi: true, isTTY: true });
     inst = logger.instance;
     log = logger('test');
   });
@@ -40,6 +40,7 @@ describe('logger', () => {
     let entry = (level, message, meta) => ({
       timestamp: jasmine.any(Number),
       debug: 'test',
+      error: false,
       level,
       message,
       meta
@@ -75,10 +76,11 @@ describe('logger', () => {
   });
 
   it('highlights info URLs blue', () => {
-    log.info('URL: https://percy.io');
+    let url = 'https://percy.io/?foo[bar]=baz&qux=quux:xyzzy;';
+    log.info(`URL: ${url}`);
 
     expect(helpers.stdout).toEqual([
-      `[${colors.magenta('percy')}] URL: ${colors.blue('https://percy.io')}`
+      `[${colors.magenta('percy')}] URL: ${colors.blue(url)}`
     ]);
   });
 
@@ -91,6 +93,7 @@ describe('logger', () => {
       level: 'error',
       message: error.stack,
       timestamp: jasmine.any(Number),
+      error: true,
       meta: {}
     });
 
@@ -129,7 +132,8 @@ describe('logger', () => {
       level: 'info',
       message: 'Yes me',
       timestamp: jasmine.any(Number),
-      meta: { match: true }
+      meta: { match: true },
+      error: false
     }]);
   });
 
@@ -171,6 +175,32 @@ describe('logger', () => {
     expect(logger.stderr).toBe(logger.constructor.stderr);
   });
 
+  it('can define a custom instance write method', () => {
+    let write = logger.instance.write = jasmine.createSpy('write');
+
+    log.info('Info log');
+    log.warn('Warn log');
+    log.error('Error log');
+    log.debug('Debug log');
+
+    expect(write).toHaveBeenCalledWith(jasmine.objectContaining(
+      { debug: 'test', level: 'info', message: 'Info log' }));
+    expect(write).toHaveBeenCalledWith(jasmine.objectContaining(
+      { debug: 'test', level: 'warn', message: 'Warn log' }));
+    expect(write).toHaveBeenCalledWith(jasmine.objectContaining(
+      { debug: 'test', level: 'error', message: 'Error log' }));
+
+    // write is not called when a log should not be written
+    expect(write).not.toHaveBeenCalledWith(jasmine.objectContaining(
+      { debug: 'test', level: 'debug', message: 'Debug log' }));
+
+    log.loglevel('debug');
+    log.debug('Debug log');
+
+    expect(write).toHaveBeenCalledWith(jasmine.objectContaining(
+      { debug: 'test', level: 'debug', message: 'Debug log' }));
+  });
+
   describe('levels', () => {
     it('can be initially set by defining PERCY_LOGLEVEL', () => {
       helpers.reset();
@@ -280,7 +310,7 @@ describe('logger', () => {
 
     it('enables debug logging when PERCY_DEBUG is defined', async () => {
       process.env.PERCY_DEBUG = '*';
-      await helpers.mock({ ansi: true });
+      await helpers.mock({ ansi: true, isTTY: true });
 
       logger('test').debug('Debug log');
 
@@ -300,9 +330,9 @@ describe('logger', () => {
       logger('test:3').debug('Debug test 3');
 
       expect(helpers.stderr).toEqual([
-        `[${colors.magenta('percy:test')}] Debug test`,
-        `[${colors.magenta('percy:test:1')}] Debug test 1`,
-        `[${colors.magenta('percy:test:3')}] Debug test 3`
+        '[percy:test] Debug test',
+        '[percy:test:1] Debug test 1',
+        '[percy:test:3] Debug test 3'
       ]);
     });
 
@@ -330,7 +360,6 @@ describe('logger', () => {
       spyOn(logger.stdout, 'cursorTo').and.callThrough();
       spyOn(logger.stdout, 'clearLine').and.callThrough();
       spyOn(logger.stdout, 'write').and.callThrough();
-      logger.stdout.isTTY = true;
       ({ stdout } = logger);
     });
 
@@ -401,7 +430,7 @@ describe('logger', () => {
         log.progress('baz');
 
         expect(stdout.cursorTo).not.toHaveBeenCalled();
-        expect(stdout.write).toHaveBeenCalledWith(`[${colors.magenta('percy')}] foo\n`);
+        expect(stdout.write).toHaveBeenCalledWith('[percy] foo\n');
         expect(stdout.clearLine).not.toHaveBeenCalled();
       });
 
@@ -413,7 +442,7 @@ describe('logger', () => {
 
         expect(stdout.cursorTo).not.toHaveBeenCalled();
         expect(stdout.clearLine).not.toHaveBeenCalled();
-        expect(stdout.write).toHaveBeenCalledWith(`[${colors.magenta('percy')}] bar\n`);
+        expect(stdout.write).toHaveBeenCalledWith('[percy] bar\n');
       });
 
       it('ignores consecutive persistant logs after the first', () => {
@@ -424,10 +453,10 @@ describe('logger', () => {
 
         expect(stdout.cursorTo).not.toHaveBeenCalled();
         expect(stdout.write).toHaveBeenCalledTimes(3);
-        expect(stdout.write).toHaveBeenCalledWith(`[${colors.magenta('percy')}] foo\n`);
-        expect(stdout.write).toHaveBeenCalledWith(`[${colors.magenta('percy')}] bar\n`);
-        expect(stdout.write).not.toHaveBeenCalledWith(`[${colors.magenta('percy')}] baz\n`);
-        expect(stdout.write).toHaveBeenCalledWith(`[${colors.magenta('percy')}] qux\n`);
+        expect(stdout.write).toHaveBeenCalledWith('[percy] foo\n');
+        expect(stdout.write).toHaveBeenCalledWith('[percy] bar\n');
+        expect(stdout.write).not.toHaveBeenCalledWith('[percy] baz\n');
+        expect(stdout.write).toHaveBeenCalledWith('[percy] qux\n');
         expect(stdout.clearLine).not.toHaveBeenCalled();
       });
     });