From 632005d221f2a5c60045769208c4b442d69cf3e5 Mon Sep 17 00:00:00 2001
From: Rudy Celekli <rudy@gradiahq.com>
Date: Sun, 11 Oct 2026 09:33:27 -0400
Subject: [PATCH 1/7] fix(director): seek camera longitude across the shortest
 dateline arc

---
 CHANGELOG.md                                 |  2 ++
 docs/CURRENT-STATE.md                        |  5 ++++
 src/director/director-dateline-seek.test.mjs | 26 ++++++++++++++++++++
 src/director/timeline.js                     |  8 +++++-
 4 files changed, 40 insertions(+), 1 deletion(-)
 create mode 100644 src/director/director-dateline-seek.test.mjs

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7acdedf6b..2075effa9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,8 @@
   the five borough cores load and `CCTV_NYC_MAX_SOURCES` changes the cap. The catalog-wide ceiling is
   unchanged; extra cameras share it round-robin with the other packs.
 
+- Director timeline seeks cross the dateline along the short longitude arc.
+
 - Treat explicitly current, complete empty vessel coverage as a successful update,
   clearing obsolete contacts while retaining stale or incomplete snapshots.
 
diff --git a/docs/CURRENT-STATE.md b/docs/CURRENT-STATE.md
index c77d1d8e3..cb0b43c54 100644
--- a/docs/CURRENT-STATE.md
+++ b/docs/CURRENT-STATE.md
@@ -5310,3 +5310,8 @@ datacenters, dams and the Nepal locator retain that shared credit while displaye
 
 Military fragments stitch by source identity. Different mapped parcels merge only
 when their footprints touch or contain one another, never across a seam tolerance gap.
+
+
+### fix(director): seek camera longitude across the shortest dateline arc
+
+Interpolate longitude with the existing shortest-angle easing, normalize intermediate longitudes, and preserve exact authored endpoints at progress zero and one.
diff --git a/src/director/director-dateline-seek.test.mjs b/src/director/director-dateline-seek.test.mjs
new file mode 100644
index 000000000..f950814f3
--- /dev/null
+++ b/src/director/director-dateline-seek.test.mjs
@@ -0,0 +1,26 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { cameraAtProgress } from './timeline.js';
+const camera = (lon) => ({
+  lat: 10,
+  lon,
+  alt: 1000,
+  heading: 0,
+  pitch: -40,
+  roll: 0,
+});
+test('director seek follows the short dateline arc in both directions', () => {
+  for (const [a, b] of [
+    [179, -179],
+    [-179, 179],
+  ]) {
+    assert.equal(
+      Math.abs(cameraAtProgress(camera(a), camera(b), 0.5).lon),
+      180,
+    );
+    assert.equal(cameraAtProgress(camera(a), camera(b), 0).lon, a);
+    assert.equal(cameraAtProgress(camera(a), camera(b), 1).lon, b);
+    assert.ok(Math.abs(cameraAtProgress(camera(a), camera(b), 0.25).lon) > 179);
+  }
+  assert.equal(cameraAtProgress(camera(20), camera(24), 0.5).lon, 22);
+});
diff --git a/src/director/timeline.js b/src/director/timeline.js
index 7fd4cbbae..1da08d498 100644
--- a/src/director/timeline.js
+++ b/src/director/timeline.js
@@ -45,7 +45,13 @@ export function cameraAtProgress(fromCamera, toCamera, progress) {
   };
   return {
     lat: lerp(source.lat, target.lat),
-    lon: lerp(source.lon, target.lon),
+    lon:
+      t === 0
+        ? Number(source.lon)
+        : t === 1
+          ? Number(target.lon)
+          : ((((lerpAngle(source.lon, target.lon) + 180) % 360) + 360) % 360) -
+            180,
     alt: lerp(source.alt, target.alt),
     heading: lerpAngle(source.heading, target.heading),
     pitch: lerp(source.pitch, target.pitch),

From 3b08bd74872a4a7c2dac103139a05ce660fd71f0 Mon Sep 17 00:00:00 2001
From: Rudy Celekli <rudy@gradiahq.com>
Date: Mon, 12 Oct 2026 11:12:42 -0400
Subject: [PATCH 2/7] fix: address review feedback for PR #1023

---
 docs/CURRENT-STATE.md    | 6 +-----
 src/director/camera.js   | 7 ++++++-
 src/director/timeline.js | 4 ++--
 3 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/docs/CURRENT-STATE.md b/docs/CURRENT-STATE.md
index cb0b43c54..37a9e6c0a 100644
--- a/docs/CURRENT-STATE.md
+++ b/docs/CURRENT-STATE.md
@@ -399,6 +399,7 @@ camera moves with easing, duration and holds. Playback and seek share one
 coordinate sampler; navigation/manual input revokes authored motion and pending
 holds. Anchor heights and explicit endpoints require the WGS84 ellipsoid
 reference. Legacy projects retain their ordinary flights, content and edits.
+Seeking between ordinary camera poses uses the shortest longitude arc across the dateline while preserving both authored endpoint longitudes.
 See [camera directions](DIRECTOR-CAMERA.md).
 
 Realtime voice composes separate connection, response/tool, Radio handoff, input
@@ -5310,8 +5311,3 @@ datacenters, dams and the Nepal locator retain that shared credit while displaye
 
 Military fragments stitch by source identity. Different mapped parcels merge only
 when their footprints touch or contain one another, never across a seam tolerance gap.
-
-
-### fix(director): seek camera longitude across the shortest dateline arc
-
-Interpolate longitude with the existing shortest-angle easing, normalize intermediate longitudes, and preserve exact authored endpoints at progress zero and one.
diff --git a/src/director/camera.js b/src/director/camera.js
index 059c7a873..e009c2cba 100644
--- a/src/director/camera.js
+++ b/src/director/camera.js
@@ -28,6 +28,11 @@ export function resolveCameraMove(scene, shot) {
   };
 }
 
+/** Wrap an interpolated camera longitude to WGS84 without changing authored endpoints. */
+export function normalizeCameraLongitude(longitude) {
+  return ((((longitude + 180) % 360) + 360) % 360) - 180;
+}
+
 /** Sample the same authored curve for playback and seeking, taking the short longitude/angle arc. */
 export function sampleCameraMove(move, progress) {
   const t = Math.max(0, Math.min(1, Number(progress) || 0));
@@ -45,7 +50,7 @@ export function sampleCameraMove(move, progress) {
   const { from, to } = move;
   return {
     lat: lerp(from.lat, to.lat),
-    lon: ((((angle(from.lon, to.lon) + 180) % 360) + 360) % 360) - 180,
+    lon: normalizeCameraLongitude(angle(from.lon, to.lon)),
     alt: lerp(from.alt, to.alt),
     heading: angle(from.heading, to.heading),
     pitch: lerp(from.pitch, to.pitch),
diff --git a/src/director/timeline.js b/src/director/timeline.js
index 1da08d498..fbaca4301 100644
--- a/src/director/timeline.js
+++ b/src/director/timeline.js
@@ -2,6 +2,7 @@ import {
   resolveCameraPose,
   resolveCameraMove,
   sampleCameraMove,
+  normalizeCameraLongitude,
 } from './camera.js';
 
 const DEFAULT_SHOT_DURATION_SEC = 4;
@@ -50,8 +51,7 @@ export function cameraAtProgress(fromCamera, toCamera, progress) {
         ? Number(source.lon)
         : t === 1
           ? Number(target.lon)
-          : ((((lerpAngle(source.lon, target.lon) + 180) % 360) + 360) % 360) -
-            180,
+          : normalizeCameraLongitude(lerpAngle(source.lon, target.lon)),
     alt: lerp(source.alt, target.alt),
     heading: lerpAngle(source.heading, target.heading),
     pitch: lerp(source.pitch, target.pitch),

From 2c5fb039ce1da3b0ce7ba9e177499b16c14c4656 Mon Sep 17 00:00:00 2001
From: Rudy Celekli <rudy@gradiahq.com>
Date: Sun, 11 Oct 2026 09:33:43 -0400
Subject: [PATCH 3/7] fix(tools): enforce string schema lengths by Unicode code
 point

---
 CHANGELOG.md                              |  2 ++
 docs/CURRENT-STATE.md                     |  5 +++++
 src/tools/schema.js                       |  5 +++--
 src/tools/tool-schema-codepoints.test.mjs | 20 ++++++++++++++++++++
 4 files changed, 30 insertions(+), 2 deletions(-)
 create mode 100644 src/tools/tool-schema-codepoints.test.mjs

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7acdedf6b..f7607fd02 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,8 @@
   the five borough cores load and `CCTV_NYC_MAX_SOURCES` changes the cap. The catalog-wide ceiling is
   unchanged; extra cameras share it round-robin with the other packs.
 
+- Tool string length validation counts Unicode characters correctly, including characters outside the basic multilingual plane.
+
 - Treat explicitly current, complete empty vessel coverage as a successful update,
   clearing obsolete contacts while retaining stale or incomplete snapshots.
 
diff --git a/docs/CURRENT-STATE.md b/docs/CURRENT-STATE.md
index c77d1d8e3..7e1970768 100644
--- a/docs/CURRENT-STATE.md
+++ b/docs/CURRENT-STATE.md
@@ -5310,3 +5310,8 @@ datacenters, dams and the Nepal locator retain that shared credit while displaye
 
 Military fragments stitch by source identity. Different mapped parcels merge only
 when their footprints touch or contain one another, never across a seam tolerance gap.
+
+
+### fix(tools): enforce string schema lengths by Unicode code point
+
+Count code points for minLength and maxLength, preserving ASCII behavior and regular-expression validation.
diff --git a/src/tools/schema.js b/src/tools/schema.js
index 7c40c3eb5..cdb63cfc1 100644
--- a/src/tools/schema.js
+++ b/src/tools/schema.js
@@ -106,9 +106,10 @@ export function validateValue(schema, value, path = 'arguments') {
         fail('must be a string');
         break;
       }
-      if (schema.minLength != null && value.length < schema.minLength)
+      const length = [...value].length;
+      if (schema.minLength != null && length < schema.minLength)
         fail(`must be at least ${schema.minLength} characters`);
-      if (schema.maxLength != null && value.length > schema.maxLength)
+      if (schema.maxLength != null && length > schema.maxLength)
         fail(`must be at most ${schema.maxLength} characters`);
       if (
         schema.pattern !== undefined &&
diff --git a/src/tools/tool-schema-codepoints.test.mjs b/src/tools/tool-schema-codepoints.test.mjs
new file mode 100644
index 000000000..c379b77e9
--- /dev/null
+++ b/src/tools/tool-schema-codepoints.test.mjs
@@ -0,0 +1,20 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { validateValue } from './schema.js';
+test('tool string schemas count Unicode characters rather than UTF-16 units', () => {
+  const value = '𠮷野家😀';
+  assert.deepEqual(validateValue({ type: 'string', maxLength: 4 }, value), []);
+  assert.equal(
+    validateValue({ type: 'string', minLength: 5 }, value).length,
+    1,
+  );
+  assert.equal(
+    validateValue({ type: 'string', maxLength: 3 }, value).length,
+    1,
+  );
+  assert.deepEqual(
+    validateValue({ type: 'string', minLength: 4, maxLength: 4 }, 'abcd'),
+    [],
+  );
+  assert.equal(validateValue({ type: 'string', minLength: 2 }, '𠮷').length, 1);
+});

From 615ba9a00826a50c2907184b9193c6e6d51bdc0b Mon Sep 17 00:00:00 2001
From: Rudy Celekli <rudy@gradiahq.com>
Date: Mon, 12 Oct 2026 11:12:53 -0400
Subject: [PATCH 4/7] fix: address review feedback for PR #1026

---
 docs/CURRENT-STATE.md | 7 ++-----
 src/tools/schema.js   | 3 ++-
 2 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/docs/CURRENT-STATE.md b/docs/CURRENT-STATE.md
index 7e1970768..e66800fd5 100644
--- a/docs/CURRENT-STATE.md
+++ b/docs/CURRENT-STATE.md
@@ -73,6 +73,8 @@ Windows/Claude Desktop Cowork confirmation remains outstanding (#927).
 
 ## Tools and local MCP server — October 1, 2026
 
+Tool argument string lengths follow JSON Schema Unicode code-point counts, so supplementary characters count once rather than as two UTF-16 units.
+
 `gods-eye-view/tools` defines queries that answer questions from the app's data,
 and `gods-eye-view/tools/mcp` exposes a composed catalog over the Model Context
 Protocol. `npm run mcp` serves Core's tools over stdio to a local MCP client,
@@ -5310,8 +5312,3 @@ datacenters, dams and the Nepal locator retain that shared credit while displaye
 
 Military fragments stitch by source identity. Different mapped parcels merge only
 when their footprints touch or contain one another, never across a seam tolerance gap.
-
-
-### fix(tools): enforce string schema lengths by Unicode code point
-
-Count code points for minLength and maxLength, preserving ASCII behavior and regular-expression validation.
diff --git a/src/tools/schema.js b/src/tools/schema.js
index cdb63cfc1..b6e8e2fd0 100644
--- a/src/tools/schema.js
+++ b/src/tools/schema.js
@@ -106,7 +106,8 @@ export function validateValue(schema, value, path = 'arguments') {
         fail('must be a string');
         break;
       }
-      const length = [...value].length;
+      let length = 0;
+      for (const character of value) length += 1;
       if (schema.minLength != null && length < schema.minLength)
         fail(`must be at least ${schema.minLength} characters`);
       if (schema.maxLength != null && length > schema.maxLength)

From cbefd529f9ca08d55e874240142d495cdf1d342f Mon Sep 17 00:00:00 2001
From: Sameh Khamis <sameh@halfpixel.ai>
Date: Wed, 14 Oct 2026 15:05:05 -0700
Subject: [PATCH 5/7] fix(director): turn heading and roll the short way for
 any authored angle
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

A single % made the seek delta negative when the target angle was more than
540° below the start, so 350° to -350° turned 340° through 180°. Uses the
same double modulo as playback, and adds tests for exact ±180° endpoints and
a near-antipodal seek.
---
 docs/CURRENT-STATE.md                        |  4 ++-
 src/director/director-dateline-seek.test.mjs | 27 ++++++++++++++++++++
 src/director/timeline.js                     |  4 ++-
 3 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/docs/CURRENT-STATE.md b/docs/CURRENT-STATE.md
index fa48b7bfe..3a7f7b94f 100644
--- a/docs/CURRENT-STATE.md
+++ b/docs/CURRENT-STATE.md
@@ -399,7 +399,9 @@ camera moves with easing, duration and holds. Playback and seek share one
 coordinate sampler; navigation/manual input revokes authored motion and pending
 holds. Anchor heights and explicit endpoints require the WGS84 ellipsoid
 reference. Legacy projects retain their ordinary flights, content and edits.
-Seeking between ordinary camera poses uses the shortest longitude arc across the dateline while preserving both authored endpoint longitudes.
+Seeking between ordinary camera poses uses the shortest longitude arc across the
+dateline while preserving both authored endpoint longitudes, and turns heading
+and roll the short way for any authored angles.
 See [camera directions](DIRECTOR-CAMERA.md).
 
 Realtime voice composes separate connection, response/tool, Radio handoff, input
diff --git a/src/director/director-dateline-seek.test.mjs b/src/director/director-dateline-seek.test.mjs
index f950814f3..b0dd2b24b 100644
--- a/src/director/director-dateline-seek.test.mjs
+++ b/src/director/director-dateline-seek.test.mjs
@@ -24,3 +24,30 @@ test('director seek follows the short dateline arc in both directions', () => {
   }
   assert.equal(cameraAtProgress(camera(20), camera(24), 0.5).lon, 22);
 });
+
+test('director seek keeps exact ±180 endpoints and picks the short arc near the antipode', () => {
+  for (const [a, b] of [
+    [180, -180],
+    [-180, 180],
+  ]) {
+    assert.equal(cameraAtProgress(camera(a), camera(b), 0).lon, a);
+    assert.equal(cameraAtProgress(camera(a), camera(b), 1).lon, b);
+    assert.equal(
+      Math.abs(cameraAtProgress(camera(a), camera(b), 0.5).lon),
+      180,
+    );
+  }
+  // 10°E to 169.9°W is 179.9° westward through Greenwich, not 180.1° east.
+  const mid = cameraAtProgress(camera(10), camera(-169.9), 0.5).lon;
+  assert.ok(mid > -81 && mid < -79, `short arc midpoint, got ${mid}`);
+});
+
+test('director seek turns heading and roll the short way for any authored angles', () => {
+  const pose = (heading, roll) => ({ ...camera(0), heading, roll });
+  const mid = cameraAtProgress(pose(350, 350), pose(-350, -350), 0.5);
+  // 350° and -350° are 20° apart through 0°/360°, not 340° through 180°.
+  for (const value of [mid.heading, mid.roll]) {
+    const wrapped = ((value % 360) + 360) % 360;
+    assert.ok(wrapped < 1e-9 || 360 - wrapped < 1e-9, `got ${value}`);
+  }
+});
diff --git a/src/director/timeline.js b/src/director/timeline.js
index fbaca4301..f7cffcece 100644
--- a/src/director/timeline.js
+++ b/src/director/timeline.js
@@ -41,7 +41,9 @@ export function cameraAtProgress(fromCamera, toCamera, progress) {
   const lerp = (from, to) => Number(from) + (Number(to) - Number(from)) * eased;
   const lerpAngle = (from, to) => {
     const start = Number(from) || 0;
-    const delta = ((Number(to) - start + 540) % 360) - 180;
+    // Double modulo keeps the delta in [-180, 180) for any authored angles,
+    // as sampleCameraMove does; a single % goes negative below -540.
+    const delta = ((((Number(to) - start + 540) % 360) + 360) % 360) - 180;
     return start + delta * eased;
   };
   return {

From c12938cd05b843ca00e8bf0ac4be5d5c5770acaa Mon Sep 17 00:00:00 2001
From: Sameh Khamis <sameh@halfpixel.ai>
Date: Wed, 14 Oct 2026 15:05:40 -0700
Subject: [PATCH 6/7] perf(tools): stop counting string code points once the
 bounds are decided

Strings without length bounds are not counted, and counting stops at the
larger bound, so a huge tool argument costs no more than its limit.
---
 src/tools/schema.js                       | 20 ++++++++++++++------
 src/tools/tool-schema-codepoints.test.mjs | 13 +++++++++++++
 2 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/src/tools/schema.js b/src/tools/schema.js
index b6e8e2fd0..f857825a1 100644
--- a/src/tools/schema.js
+++ b/src/tools/schema.js
@@ -106,12 +106,20 @@ export function validateValue(schema, value, path = 'arguments') {
         fail('must be a string');
         break;
       }
-      let length = 0;
-      for (const character of value) length += 1;
-      if (schema.minLength != null && length < schema.minLength)
-        fail(`must be at least ${schema.minLength} characters`);
-      if (schema.maxLength != null && length > schema.maxLength)
-        fail(`must be at most ${schema.maxLength} characters`);
+      if (schema.minLength != null || schema.maxLength != null) {
+        // Code points, as JSON Schema counts. Counting stops once both bounds
+        // are decided, so a huge argument costs no more than its limit.
+        const limit = Math.max(
+          schema.minLength ?? 0,
+          schema.maxLength != null ? schema.maxLength + 1 : 0,
+        );
+        let length = 0;
+        for (const _ of value) if (++length >= limit) break;
+        if (schema.minLength != null && length < schema.minLength)
+          fail(`must be at least ${schema.minLength} characters`);
+        if (schema.maxLength != null && length > schema.maxLength)
+          fail(`must be at most ${schema.maxLength} characters`);
+      }
       if (
         schema.pattern !== undefined &&
         !new RegExp(schema.pattern, 'u').test(value)
diff --git a/src/tools/tool-schema-codepoints.test.mjs b/src/tools/tool-schema-codepoints.test.mjs
index c379b77e9..27af78fa3 100644
--- a/src/tools/tool-schema-codepoints.test.mjs
+++ b/src/tools/tool-schema-codepoints.test.mjs
@@ -18,3 +18,16 @@ test('tool string schemas count Unicode characters rather than UTF-16 units', ()
   );
   assert.equal(validateValue({ type: 'string', minLength: 2 }, '𠮷').length, 1);
 });
+
+test('tool string bounds hold at their edges and on huge arguments', () => {
+  const string = (bounds) => ({ type: 'string', ...bounds });
+  assert.deepEqual(validateValue(string({ maxLength: 3 }), '😀😀😀'), []);
+  assert.equal(validateValue(string({ maxLength: 3 }), '😀😀😀😀').length, 1);
+  assert.deepEqual(validateValue(string({ minLength: 3 }), '😀😀😀'), []);
+  assert.deepEqual(validateValue(string({}), 'x'.repeat(1e6)), []);
+  // Counting all of it takes roughly 0.7 s; stopping at the limit takes none.
+  const huge = 'x'.repeat(1e8);
+  const started = performance.now();
+  assert.equal(validateValue(string({ maxLength: 60 }), huge).length, 1);
+  assert.ok(performance.now() - started < 200, 'stops counting past the limit');
+});

From e50bc45674c4e7f940dce07f3c67b7c1ed83fb67 Mon Sep 17 00:00:00 2001
From: quanticsoul4772 <71096528+quanticsoul4772@users.noreply.github.com>
Date: Wed, 14 Oct 2026 15:36:35 -0700
Subject: [PATCH 7/7] fix(qa): run the macOS-only gates on Windows and Linux
 (#1061)

Seven QA scripts hard-coded macOS Google Chrome. They now share chromeExecutablePath(): PUPPETEER_EXECUTABLE_PATH when set, then macOS Chrome when installed, otherwise Puppeteer's managed browser. The cables screenshot path is built with fileURLToPath so it works on Windows. qa-overlay-baseline keeps its fixed Chrome because its baselines record the executable.

Co-authored-by: Sameh Khamis <sameh@halfpixel.ai>
---
 scripts/format-scope.json           |  2 ++
 scripts/precompute-cctv-heights.mjs |  4 ++--
 scripts/qa-cables-shot.mjs          |  5 ++++-
 scripts/qa-chrome.mjs               | 20 ++++++++++++++++++++
 scripts/qa-directions.mjs           |  4 ++--
 scripts/qa-draw-tool.mjs            |  4 ++--
 scripts/qa-recent-imagery.mjs       |  4 ++--
 scripts/qa-transit-heading.mjs      |  4 ++--
 scripts/qa-transit-recovery.mjs     |  4 ++--
 scripts/qa-transit.mjs              |  4 ++--
 src/qaChrome.test.mjs               | 27 +++++++++++++++++++++++++++
 11 files changed, 67 insertions(+), 15 deletions(-)
 create mode 100644 scripts/qa-chrome.mjs
 create mode 100644 src/qaChrome.test.mjs

diff --git a/scripts/format-scope.json b/scripts/format-scope.json
index 1a880b284..296880561 100644
--- a/scripts/format-scope.json
+++ b/scripts/format-scope.json
@@ -934,6 +934,8 @@
   "scripts/qa-street-level.mjs",
   "src/tooling/streetLevelQa.test.mjs",
   "scripts/qa-browserEvidence.mjs",
+  "scripts/qa-chrome.mjs",
+  "src/qaChrome.test.mjs",
   "scripts/fixtures/street-level/mapillaryGraph.mjs",
   "scripts/fixtures/street-level/kartaView.mjs",
   "src/layers/streetLevel/filter.test.mjs",
diff --git a/scripts/precompute-cctv-heights.mjs b/scripts/precompute-cctv-heights.mjs
index 24813b5e7..648768341 100644
--- a/scripts/precompute-cctv-heights.mjs
+++ b/scripts/precompute-cctv-heights.mjs
@@ -1,6 +1,7 @@
 import { mkdir, readFile, rename, rm, writeFile } from 'node:fs/promises';
 import path from 'node:path';
 import { fileURLToPath, pathToFileURL } from 'node:url';
+import { chromeExecutablePath } from './qa-chrome.mjs';
 import {
   planeSupportPoints,
   poseHash,
@@ -389,8 +390,7 @@ async function main() {
       const { default: puppeteer } = await import('puppeteer');
       browser = await puppeteer.launch({
         headless: false,
-        executablePath:
-          '/Applications/Google Chrome.app/Contents/MacOS/Google Chrome',
+        executablePath: chromeExecutablePath(),
         protocolTimeout: 600000,
         args: [
           '--no-sandbox',
diff --git a/scripts/qa-cables-shot.mjs b/scripts/qa-cables-shot.mjs
index 12af9beb8..3e3008e03 100644
--- a/scripts/qa-cables-shot.mjs
+++ b/scripts/qa-cables-shot.mjs
@@ -6,6 +6,7 @@
  */
 import puppeteer from 'puppeteer';
 import { mkdirSync } from 'node:fs';
+import { fileURLToPath } from 'node:url';
 
 const argv = process.argv;
 const url = argv.includes('--url') ? argv[argv.indexOf('--url') + 1] : 'http://localhost:4214';
@@ -65,7 +66,9 @@ try {
       requestAnimationFrame(tick);
     }));
     await new Promise((r) => setTimeout(r, 1_000));
-    const path = new URL(`../qa-shots/cables-${tag}-${view.name}.png`, import.meta.url).pathname;
+    const path = fileURLToPath(
+      new URL(`../qa-shots/cables-${tag}-${view.name}.png`, import.meta.url),
+    );
     await page.screenshot({ path });
     console.log(`saved ${path}`);
   }
diff --git a/scripts/qa-chrome.mjs b/scripts/qa-chrome.mjs
new file mode 100644
index 000000000..05c4dbff0
--- /dev/null
+++ b/scripts/qa-chrome.mjs
@@ -0,0 +1,20 @@
+/**
+ * The browser for gates that drive an installed Chrome. These gates were
+ * written against macOS Google Chrome, which Windows and Linux do not have.
+ */
+import { existsSync } from 'node:fs';
+
+export const MACOS_CHROME =
+  '/Applications/Google Chrome.app/Contents/MacOS/Google Chrome';
+
+/**
+ * PUPPETEER_EXECUTABLE_PATH when set, then macOS Google Chrome when it is
+ * installed. Otherwise undefined, so Puppeteer launches the browser it manages.
+ */
+export function chromeExecutablePath({
+  env = process.env,
+  exists = existsSync,
+} = {}) {
+  if (env.PUPPETEER_EXECUTABLE_PATH) return env.PUPPETEER_EXECUTABLE_PATH;
+  return exists(MACOS_CHROME) ? MACOS_CHROME : undefined;
+}
diff --git a/scripts/qa-directions.mjs b/scripts/qa-directions.mjs
index 9501690f9..ca271026f 100644
--- a/scripts/qa-directions.mjs
+++ b/scripts/qa-directions.mjs
@@ -10,6 +10,7 @@ import fs from 'node:fs/promises';
 import path from 'node:path';
 import { fileURLToPath } from 'node:url';
 import puppeteer from 'puppeteer';
+import { chromeExecutablePath } from './qa-chrome.mjs';
 
 const ROOT = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '..');
 const args = process.argv.slice(2);
@@ -35,8 +36,7 @@ const check = (name, passed, detail = '') => {
 
 const browser = await puppeteer.launch({
   headless: false,
-  executablePath:
-    '/Applications/Google Chrome.app/Contents/MacOS/Google Chrome',
+  executablePath: chromeExecutablePath(),
   args: [
     '--no-sandbox',
     '--disable-background-timer-throttling',
diff --git a/scripts/qa-draw-tool.mjs b/scripts/qa-draw-tool.mjs
index a5a16af1d..adb29f3af 100644
--- a/scripts/qa-draw-tool.mjs
+++ b/scripts/qa-draw-tool.mjs
@@ -3,6 +3,7 @@
 import fs from 'node:fs';
 import path from 'node:path';
 import puppeteer from 'puppeteer';
+import { chromeExecutablePath } from './qa-chrome.mjs';
 
 const BASE_URL = process.env.QA_BASE_URL || 'http://localhost:4173';
 const SHOT_DIR = process.env.QA_SHOT_DIR || 'qa-shots/draw';
@@ -22,8 +23,7 @@ const browser = await puppeteer.launch({
   headless: !HEADFUL,
   ...(HEADFUL
     ? {
-        executablePath:
-          '/Applications/Google Chrome.app/Contents/MacOS/Google Chrome',
+        executablePath: chromeExecutablePath(),
       }
     : {}),
   args: [
diff --git a/scripts/qa-recent-imagery.mjs b/scripts/qa-recent-imagery.mjs
index 5d42279dc..89d60d96f 100644
--- a/scripts/qa-recent-imagery.mjs
+++ b/scripts/qa-recent-imagery.mjs
@@ -20,6 +20,7 @@
 import fs from 'node:fs';
 import path from 'node:path';
 import puppeteer from 'puppeteer';
+import { chromeExecutablePath } from './qa-chrome.mjs';
 
 const BASE_URL = process.env.QA_BASE_URL || 'http://localhost:4173';
 const SHOT_DIR = process.env.QA_SHOT_DIR || 'qa-shots/recent-imagery';
@@ -54,8 +55,7 @@ const browser = await puppeteer.launch({
   headless: !HEADFUL,
   ...(HEADFUL
     ? {
-        executablePath:
-          '/Applications/Google Chrome.app/Contents/MacOS/Google Chrome',
+        executablePath: chromeExecutablePath(),
       }
     : {}),
   args: [
diff --git a/scripts/qa-transit-heading.mjs b/scripts/qa-transit-heading.mjs
index a16bab9bc..c229be96c 100644
--- a/scripts/qa-transit-heading.mjs
+++ b/scripts/qa-transit-heading.mjs
@@ -1,11 +1,11 @@
 import puppeteer from 'puppeteer';
+import { chromeExecutablePath } from './qa-chrome.mjs';
 
 /** Prove parked and moving headings in the real scene, without live feeds. */
 export async function runTransitHeadingRegression(base, check) {
   const browser = await puppeteer.launch({
     headless: true,
-    executablePath:
-      '/Applications/Google Chrome.app/Contents/MacOS/Google Chrome',
+    executablePath: chromeExecutablePath(),
     args: ['--no-sandbox', '--disable-background-timer-throttling'],
   });
   try {
diff --git a/scripts/qa-transit-recovery.mjs b/scripts/qa-transit-recovery.mjs
index e5fadda49..5f6404b41 100644
--- a/scripts/qa-transit-recovery.mjs
+++ b/scripts/qa-transit-recovery.mjs
@@ -1,5 +1,6 @@
 /** Camera-jump regression against an existing server; never starts a server. */
 import puppeteer from 'puppeteer';
+import { chromeExecutablePath } from './qa-chrome.mjs';
 import { mkdir, writeFile } from 'node:fs/promises';
 import { reduceTrailPixels } from '../src/layers/transit/qaMetrics.js';
 
@@ -8,8 +9,7 @@ const shots = process.env.QA_SHOTS || 'qa-shots/transit-recovery';
 await mkdir(shots, { recursive: true });
 const browser = await puppeteer.launch({
   headless: false,
-  executablePath:
-    '/Applications/Google Chrome.app/Contents/MacOS/Google Chrome',
+  executablePath: chromeExecutablePath(),
   args: [
     '--disable-background-timer-throttling',
     '--disable-renderer-backgrounding',
diff --git a/scripts/qa-transit.mjs b/scripts/qa-transit.mjs
index aac1d8f60..7d83d77a4 100644
--- a/scripts/qa-transit.mjs
+++ b/scripts/qa-transit.mjs
@@ -36,6 +36,7 @@ import {
  */
 import { mkdir, readFile, writeFile } from 'node:fs/promises';
 import puppeteer from 'puppeteer';
+import { chromeExecutablePath } from './qa-chrome.mjs';
 import { createTransitHistory } from '../server/providers/transitHistory.js';
 import { DETECTION_THEME_MAP } from '../src/overlays/worldOverlayTokens.js';
 import { transitModeTier } from '../src/data/transitPresetStyle.js';
@@ -262,8 +263,7 @@ await mkdir(SHOTS, { recursive: true });
 const browser = await puppeteer.launch({
   headless: false,
   protocolTimeout: 150000,
-  executablePath:
-    '/Applications/Google Chrome.app/Contents/MacOS/Google Chrome',
+  executablePath: chromeExecutablePath(),
   args: [
     '--no-sandbox',
     '--disable-background-timer-throttling',
diff --git a/src/qaChrome.test.mjs b/src/qaChrome.test.mjs
new file mode 100644
index 000000000..4414f3c93
--- /dev/null
+++ b/src/qaChrome.test.mjs
@@ -0,0 +1,27 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import { MACOS_CHROME, chromeExecutablePath } from '../scripts/qa-chrome.mjs';
+
+test('gates keep macOS Chrome where it is installed', () => {
+  assert.equal(
+    chromeExecutablePath({ env: {}, exists: (p) => p === MACOS_CHROME }),
+    MACOS_CHROME,
+  );
+});
+
+test('gates fall back to Puppeteer’s browser without macOS Chrome', () => {
+  assert.equal(
+    chromeExecutablePath({ env: {}, exists: () => false }),
+    undefined,
+  );
+});
+
+test('an explicit executable path wins', () => {
+  assert.equal(
+    chromeExecutablePath({
+      env: { PUPPETEER_EXECUTABLE_PATH: 'C:\\Chrome\\chrome.exe' },
+      exists: () => true,
+    }),
+    'C:\\Chrome\\chrome.exe',
+  );
+});