diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2f983d057..b9ba27de1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -26,6 +26,10 @@
 
 - Weather records keep missing conditions unknown and refuse summaries without a measured temperature.
 
+- Tool string length validation counts Unicode characters correctly, including characters outside the basic multilingual plane.
+
+- 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 0ec9548ae..a53f553f5 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,
@@ -399,6 +401,9 @@ 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, 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/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/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/director-dateline-seek.test.mjs b/src/director/director-dateline-seek.test.mjs
new file mode 100644
index 000000000..b0dd2b24b
--- /dev/null
+++ b/src/director/director-dateline-seek.test.mjs
@@ -0,0 +1,53 @@
+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);
+});
+
+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 7fd4cbbae..f7cffcece 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;
@@ -40,12 +41,19 @@ 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 {
     lat: lerp(source.lat, target.lat),
-    lon: lerp(source.lon, target.lon),
+    lon:
+      t === 0
+        ? Number(source.lon)
+        : t === 1
+          ? Number(target.lon)
+          : normalizeCameraLongitude(lerpAngle(source.lon, target.lon)),
     alt: lerp(source.alt, target.alt),
     heading: lerpAngle(source.heading, target.heading),
     pitch: lerp(source.pitch, target.pitch),
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',
+  );
+});
diff --git a/src/tools/schema.js b/src/tools/schema.js
index 7c40c3eb5..f857825a1 100644
--- a/src/tools/schema.js
+++ b/src/tools/schema.js
@@ -106,10 +106,20 @@ export function validateValue(schema, value, path = 'arguments') {
         fail('must be a string');
         break;
       }
-      if (schema.minLength != null && value.length < schema.minLength)
-        fail(`must be at least ${schema.minLength} characters`);
-      if (schema.maxLength != null && value.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
new file mode 100644
index 000000000..27af78fa3
--- /dev/null
+++ b/src/tools/tool-schema-codepoints.test.mjs
@@ -0,0 +1,33 @@
+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);
+});
+
+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');
+});