diff --git a/site/public/brand/companion/broken.webp b/site/public/brand/companion/broken.webp
new file mode 100644
index 00000000..5f540734
Binary files /dev/null and b/site/public/brand/companion/broken.webp differ
diff --git a/site/public/brand/companion/debug.webp b/site/public/brand/companion/debug.webp
new file mode 100644
index 00000000..fec154eb
Binary files /dev/null and b/site/public/brand/companion/debug.webp differ
diff --git a/site/public/brand/companion/hint.webp b/site/public/brand/companion/hint.webp
new file mode 100644
index 00000000..3f56f680
Binary files /dev/null and b/site/public/brand/companion/hint.webp differ
diff --git a/site/public/brand/companion/info.webp b/site/public/brand/companion/info.webp
new file mode 100644
index 00000000..83ebb2b4
Binary files /dev/null and b/site/public/brand/companion/info.webp differ
diff --git a/site/public/brand/companion/invalid.webp b/site/public/brand/companion/invalid.webp
new file mode 100644
index 00000000..28937a9e
Binary files /dev/null and b/site/public/brand/companion/invalid.webp differ
diff --git a/site/public/brand/companion/pitfall.webp b/site/public/brand/companion/pitfall.webp
new file mode 100644
index 00000000..1698d950
Binary files /dev/null and b/site/public/brand/companion/pitfall.webp differ
diff --git a/site/public/brand/companion/success.webp b/site/public/brand/companion/success.webp
new file mode 100644
index 00000000..56c2e8c1
Binary files /dev/null and b/site/public/brand/companion/success.webp differ
diff --git a/site/public/brand/companion/warning.webp b/site/public/brand/companion/warning.webp
new file mode 100644
index 00000000..730dae9d
Binary files /dev/null and b/site/public/brand/companion/warning.webp differ
diff --git a/site/src/components/Callout.astro b/site/src/components/Callout.astro
index 5ae173fb..e009af5d 100644
--- a/site/src/components/Callout.astro
+++ b/site/src/components/Callout.astro
@@ -1,58 +1,85 @@
 ---
 /**
- * Callout — a labelled aside for notes, tips, warnings, and platform hints.
+ * Callout — a labelled aside for the eight Guide Companion states.
+ *
+ * Each state pairs the painterly companion sprite (a trailing-edge badge) with a
+ * state-coloured glyph + label. The glyph and label carry the meaning, so the
+ * callout reads for colour-blind readers and in high-contrast modes; the sprite
+ * and its state-coloured screen-glow are enrichment.
  *
  * Usage in MDX:
  *   import Callout from '../../../components/Callout.astro';
  *
- *   <Callout type="tip">
- *   Start each frame with `context.backend.clear()`.
+ *   <Callout type="hint">
+ *   Pulling in several assets? `loadMany()` batches the requests for you.
  *   </Callout>
  *
- *   <Callout type="common-mistake" title="Forgetting the anchor">
+ *   <Callout type="pitfall" title="A sprite that won't center">
  *   A sprite's default anchor is the top-left corner, not its center.
  *   </Callout>
  *
- * The type is conveyed by a text label and a glyph, never colour alone, so the
- * meaning survives for colour-blind readers and in high-contrast modes.
+ * Colour exclusivity: amber=warning, mint=success, gray=invalid, red=broken;
+ * info/hint/pitfall/debug share the companion cyan and are told apart by glyph.
  */
 
-type CalloutType = 'note' | 'tip' | 'important' | 'common-mistake' | 'webgpu' | 'browser';
+type CalloutType = 'info' | 'hint' | 'warning' | 'pitfall' | 'success' | 'debug' | 'invalid' | 'broken';
 
 interface Props {
     type?: CalloutType;
-    /** Optional heading. Falls back to the type's default label. */
+    /** Optional heading. Falls back to the state's default label. */
     title?: string;
 }
 
 const META: Record<CalloutType, { label: string; glyph: string }> = {
-    'note': { label: 'Note', glyph: 'i' },
-    'tip': { label: 'Tip', glyph: '+' },
-    'important': { label: 'Important', glyph: '!' },
-    'common-mistake': { label: 'Common mistake', glyph: '×' },
-    'webgpu': { label: 'WebGPU', glyph: '◆' },
-    'browser': { label: 'Browser behavior', glyph: '◐' },
+    info: { label: 'Good to know', glyph: 'i' },
+    hint: { label: 'Tip', glyph: '✦' },
+    warning: { label: 'Heads up', glyph: '!' },
+    pitfall: { label: 'Common pitfall', glyph: '?' },
+    success: { label: "You're set", glyph: '✓' },
+    debug: { label: 'Debug tip', glyph: '[]' },
+    invalid: { label: 'Not supported', glyph: 'Ø' },
+    broken: { label: 'Runtime error', glyph: '✕' },
 };
 
-const { type = 'note', title } = Astro.props;
+const { type = 'info', title } = Astro.props;
 const meta = META[type];
 const heading = title ?? meta.label;
+const base = import.meta.env.BASE_URL;
 ---
 
 <aside class="callout" data-callout={type} role="note">
-    <p class="callout__head">
-        <span class="callout__glyph" aria-hidden="true">{meta.glyph}</span>
-        <span class="callout__label">{heading}</span>
-    </p>
-    <div class="callout__body">
-        <slot />
+    <div class="callout__main">
+        <p class="callout__head">
+            <span class="callout__glyph" aria-hidden="true">{meta.glyph}</span>
+            <span class="callout__label">{heading}</span>
+        </p>
+        <div class="callout__body">
+            <slot />
+        </div>
     </div>
+    <img
+        class="callout__companion"
+        src={`${base}brand/companion/${type}.webp`}
+        alt=""
+        aria-hidden="true"
+        width="64"
+        height="64"
+        loading="lazy"
+        decoding="async"
+    />
 </aside>
 
 <style>
     .callout {
-        --callout-accent: var(--fg-muted);
-        --callout-bg: color-mix(in oklab, var(--bg-elevated), transparent 0%);
+        /* Default state = info (companion cyan). Each state below overrides the
+           accent; the soft background is always a faint tint of that accent.
+           State colours are fixed (not derived from --accent) so they stay
+           stable across the user-selectable accent themes. */
+        --callout-accent: oklch(80% 0.1 195);
+        --callout-bg: color-mix(in oklab, var(--callout-accent), transparent 92%);
+        display: flex;
+        align-items: center;
+        gap: var(--s-4);
         margin: var(--s-5) 0;
         padding: var(--s-3) var(--s-4);
         border: 1px solid var(--line-soft);
@@ -61,6 +88,11 @@ const heading = title ?? meta.label;
         background: var(--callout-bg);
     }
 
+    .callout__main {
+        flex: 1 1 auto;
+        min-width: 0;
+    }
+
     .callout__head {
         display: flex;
         align-items: center;
@@ -76,8 +108,10 @@ const heading = title ?? meta.label;
     .callout__glyph {
         display: inline-grid;
         place-items: center;
-        width: 18px;
+        flex: 0 0 auto;
+        min-width: 18px;
         height: 18px;
+        padding: 0 4px;
         border-radius: var(--r-pill);
         border: 1px solid var(--callout-accent);
         font-size: 11px;
@@ -97,33 +131,49 @@ const heading = title ?? meta.label;
         margin-bottom: 0;
     }
 
-    .callout[data-callout='note'] {
-        --callout-accent: var(--color-text-muted);
-        --callout-bg: color-mix(in oklab, var(--color-text-muted), transparent 94%);
+    /* Trailing-edge companion badge. The sprite is delivered transparent, so it
+       sits on both themes with no card behind it; a state-coloured glow stands
+       in for the screen-glow that carries meaning at small sizes. */
+    .callout__companion {
+        flex: 0 0 auto;
+        align-self: center;
+        width: 64px;
+        height: 64px;
+        object-fit: contain;
+        filter: drop-shadow(0 0 12px color-mix(in oklab, var(--callout-accent), transparent 52%));
+    }
+
+    .callout[data-callout='info'],
+    .callout[data-callout='hint'],
+    .callout[data-callout='pitfall'],
+    .callout[data-callout='debug'] {
+        --callout-accent: oklch(80% 0.1 195); /* companion cyan #52D9D4 */
     }
 
-    .callout[data-callout='tip'] {
-        --callout-accent: var(--accent);
-        --callout-bg: var(--accent-soft);
+    .callout[data-callout='warning'] {
+        --callout-accent: oklch(78% 0.14 75); /* amber #F2A93B */
     }
 
-    .callout[data-callout='important'] {
-        --callout-accent: oklch(80% 0.13 85);
-        --callout-bg: color-mix(in oklab, oklch(80% 0.13 85), transparent 90%);
+    .callout[data-callout='success'] {
+        --callout-accent: oklch(78% 0.12 162); /* mint-green #62D29A */
     }
 
-    .callout[data-callout='common-mistake'] {
-        --callout-accent: oklch(72% 0.16 25);
-        --callout-bg: color-mix(in oklab, oklch(72% 0.16 25), transparent 90%);
+    .callout[data-callout='invalid'] {
+        --callout-accent: oklch(70% 0.01 195); /* neutral gray #9AA1A1 */
     }
 
-    .callout[data-callout='webgpu'] {
-        --callout-accent: oklch(72% 0.15 290);
-        --callout-bg: color-mix(in oklab, oklch(72% 0.15 290), transparent 90%);
+    .callout[data-callout='broken'] {
+        --callout-accent: oklch(62% 0.2 27); /* red #E0463B */
     }
 
-    .callout[data-callout='browser'] {
-        --callout-accent: oklch(74% 0.12 230);
-        --callout-bg: color-mix(in oklab, oklch(74% 0.12 230), transparent 90%);
+    @media (max-width: 560px) {
+        .callout {
+            gap: var(--s-3);
+        }
+
+        .callout__companion {
+            width: 48px;
+            height: 48px;
+        }
     }
 </style>
diff --git a/site/src/content/guide/audio/audio-basics.mdx b/site/src/content/guide/audio/audio-basics.mdx
index d07bd85a..1ea87828 100644
--- a/site/src/content/guide/audio/audio-basics.mdx
+++ b/site/src/content/guide/audio/audio-basics.mdx
@@ -60,7 +60,7 @@ if (this.app.audio.locked) {
 }
 ```
 
-<Callout type="browser" title="Audio needs a user gesture">
+<Callout type="warning" title="Audio needs a user gesture">
 Browsers won't start audio until the user interacts with the page. Trigger the first sound or music from a click, tap, or key press — the embedded examples below ask for a click for exactly this reason.
 </Callout>
 
diff --git a/site/src/content/guide/getting-started/setup.mdx b/site/src/content/guide/getting-started/setup.mdx
index 7cee9e7a..d7410927 100644
--- a/site/src/content/guide/getting-started/setup.mdx
+++ b/site/src/content/guide/getting-started/setup.mdx
@@ -75,7 +75,7 @@ const app = new Application({ canvas: { element: canvas } });
 // ...or let the application create one and mount app.canvas yourself.
 ```
 
-<Callout type="tip">
+<Callout type="hint">
 `app.canvas` is the active `HTMLCanvasElement` the runtime renders into. Append it wherever your layout needs it.
 </Callout>
 
diff --git a/site/src/content/guide/getting-started/what-is-exojs.mdx b/site/src/content/guide/getting-started/what-is-exojs.mdx
index a0758281..46a75796 100644
--- a/site/src/content/guide/getting-started/what-is-exojs.mdx
+++ b/site/src/content/guide/getting-started/what-is-exojs.mdx
@@ -47,7 +47,7 @@ ExoJS ships as ESM with TypeScript declarations. JavaScript projects can use the
 
 ExoJS targets evergreen browsers: current Chrome, Firefox, Edge, and Safari. Some examples in this guide need browser features beyond rendering — audio playback, gamepad APIs, or multi-touch input. Capability badges above each example list what it expects; when a feature is missing, the embedded preview shows a clear overlay instead of failing silently.
 
-<Callout type="browser">
+<Callout type="info">
 On startup the runtime auto-selects the strongest available backend — WebGPU when present, WebGL2 otherwise. You write the same scene code either way.
 </Callout>
 
diff --git a/site/src/content/guide/getting-started/your-first-scene.mdx b/site/src/content/guide/getting-started/your-first-scene.mdx
index 702f2262..17becef6 100644
--- a/site/src/content/guide/getting-started/your-first-scene.mdx
+++ b/site/src/content/guide/getting-started/your-first-scene.mdx
@@ -59,7 +59,7 @@ A few things worth pointing out:
 - `loader.load(Texture, { bunny: 'image/bunny.png' })` declares one asset under the name `bunny`. Inside `init`, `loader.get(Texture, 'bunny')` returns the loaded texture instance. Names are stable; paths can change later without touching the rest of the code.
 - The default sprite anchor is `(0, 0)` — the top-left. With `setAnchor(0.5)`, the sprite's center becomes its pivot point, so `setPosition(width / 2, height / 2)` places the sprite at the canvas center rather than offset to one corner.
 
-<Callout type="common-mistake" title="A sprite that won't center">
+<Callout type="pitfall" title="A sprite that won't center">
 A sprite's default anchor is its top-left corner. `setPosition(width / 2, height / 2)` then places the corner — not the center — at the middle of the canvas. Call `setAnchor(0.5)` first.
 </Callout>