diff --git a/inventory/templates/testing.html b/inventory/templates/testing.html
index e5be39f..205ce21 100644
--- a/inventory/templates/testing.html
+++ b/inventory/templates/testing.html
@@ -60,7 +60,17 @@
         <input type="color" class="form-control form-control-sm form-control-color" id="color">
         <div class="vr mx-1"></div>
         <div class="btn-group">
-            <input type="radio" class="btn-check" id="outline" name="tool" checked>
+            <input type="radio" class="btn-check" id="pen" name="tool" checked>
+            <label for="pen"
+                class="btn btn-sm btn-light border d-inline-flex align-items-center justify-content-center">
+                <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-pen"
+                    viewBox="0 0 16 16">
+                    <path
+                        d="m13.498.795.149-.149a1.207 1.207 0 1 1 1.707 1.708l-.149.148a1.5 1.5 0 0 1-.059 2.059L4.854 14.854a.5.5 0 0 1-.233.131l-4 1a.5.5 0 0 1-.606-.606l1-4a.5.5 0 0 1 .131-.232l9.642-9.642a.5.5 0 0 0-.642.056L6.854 4.854a.5.5 0 1 1-.708-.708L9.44.854A1.5 1.5 0 0 1 11.5.796a1.5 1.5 0 0 1 1.998-.001m-.644.766a.5.5 0 0 0-.707 0L1.95 11.756l-.764 3.057 3.057-.764L14.44 3.854a.5.5 0 0 0 0-.708z" />
+                </svg>
+            </label>
+
+            <input type="radio" class="btn-check" id="outline" name="tool">
             <label for="outline"
                 class="btn btn-sm btn-light border d-inline-flex align-items-center justify-content-center">
                 <svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-square"
@@ -246,6 +256,18 @@ resizeAndSetupCanvas();
 setGrid();
 scheduleSnappedcellSize();
 
+function pxToDocPoint(clientX, clientY) {
+    const rect = gridEl.getBoundingClientRect();
+    const x = Math.min(Math.max(clientX, rect.left), rect.right) - rect.left;
+    const y = Math.min(Math.max(clientY, rect.top), rect.bottom) - rect.top;
+    return { x: pxToGrid(x), y: pxToGrid(y) };
+}
+
+function dist2(a, b) {
+    const dx = a.x - b.x, dy = a.y - b.y;
+    return dx*dx + dy*dy
+}
+
 function undo() {
     if (historyIndex <= 0) return;
     historyIndex--;
@@ -280,7 +302,7 @@ function clamp01(n, fallback = 1) {
 function isFiniteNum(n) { return Number.isFinite(Number(n)); }
 
 function sanitizeShapes(list) {
-  const allowed = new Set(['rect','ellipse','line']);
+  const allowed = new Set(['rect','ellipse','line','path']);
 
   return list.flatMap((s) => {
     if (!s || typeof s !== 'object' || !allowed.has(s.type)) return [];
@@ -292,6 +314,26 @@ function sanitizeShapes(list) {
       return [{ type:'line', x1:+s.x1, y1:+s.y1, x2:+s.x2, y2:+s.y2, color }];
     }
 
+    if (s.type === 'path') {
+        if (!Array.isArray(s.points) || s.points.length < 2) return [];
+        const points = s.points.flatMap(p => {
+            if (!p || !isFiniteNum(p.x) || !isFiniteNum(p.y)) return [];
+            return [{ x: +p.x, y: +p.y }];
+        });
+        if (points.length < 2) return [];
+
+        const width = isFiniteNum(s.width) ? Math.max(0.05, +s.width) : 0.12;
+        const opacity = clamp01(s.opacity, 1);
+
+        return [{
+            type: 'path',
+            points,
+            color,
+            width,
+            opacity
+        }];
+    }
+
     if (!['x','y','w','h'].every(k => isFiniteNum(s[k]))) return [];
     return [{
       type: s.type,
@@ -550,6 +592,24 @@ function drawShape(shape) {
         ctx.moveTo(x1, y1);
         ctx.lineTo(x2, y2);
         ctx.stroke();
+    } else if (shape.type === 'path') {
+        const toPx = (v) => v * cellSize;
+
+        ctx.save();
+        ctx.strokeStyle = shape.color || '#000000';
+        ctx.globalAlpha = clamp01(shape.opacity, 1);
+
+        ctx.lineWidth = Math.max(1, toPx(shape.width ?? 0.12));
+        ctx.lineJoin = 'round';
+        ctx.lineCap = 'round';
+
+        const pts = shape.points;
+        ctx.beginPath();
+        ctx.moveTo(toPx(pts[0].x), toPx(pts[0].y));
+        for (let i = 1; i < pts.length; i++) {
+            ctx.lineTo(toPx(pts[i].x), toPx(pts[i].y));
+        }
+        ctx.stroke();
     }
 
     ctx.restore();
@@ -727,10 +787,11 @@ gridEl.addEventListener('pointermove', (e) => {
     if (!ctx) return;
 
     const { ix, iy, x: snapX, y: snapY, localX, localY } = snapToGrid(e.clientX, e.clientY);
+    const tool = getActiveTool();
 
     coordsEl.classList.remove('d-none');
 
-    if (getActiveType() !== 'noGrid') {
+    if (getActiveType() !== 'noGrid' && tool !== 'pen') {
         dotEl.classList.remove('d-none');
 
         const gridRect = gridEl.getBoundingClientRect();
@@ -758,6 +819,28 @@ gridEl.addEventListener('pointermove', (e) => {
         ctx.save();
         ctx.setLineDash([5, 3]);
 
+        if (currentShape.tool === 'pen') {
+            const p = pxToDocPoint(e.clientX, e.clientY);
+
+            const pts = currentShape.points;
+            const last = pts[pts.length - 1];
+            const minStep = 0.02;
+            if (!last || dist2(p, last) >= minStep * minStep) {
+                pts.push(p);
+            }
+
+            clearCanvas();
+            shapes.forEach(drawShape);
+
+            ctx.save();
+            ctx.setLineDash([5, 3]);
+            drawShape(currentShape);
+            ctx.setLineDash([]);
+            ctx.restore();
+
+            return;
+        }
+
         if (tool === 'line') {
             const previewLine = normalizeLine({
                 type: 'line',
@@ -837,6 +920,16 @@ gridEl.addEventListener('pointerdown', (e) => {
             fill: (tool === 'filledEllipse'),
             opacity: currentOpacity
         };
+    } else if (tool === 'pen') {
+        const p = pxToDocPoint(e.clientX, e.clientY);
+        currentShape = {
+            tool,
+            type: 'path',
+            points: [p],
+            color: selectedColor,
+            width: 0.12,
+            opacity: 1
+        };
     }
 });
 
@@ -854,6 +947,23 @@ window.addEventListener('pointerup', (e) => {
 
     let finalShape = null;
 
+    if (currentShape.tool === 'pen') {
+        const pts = currentShape.points;
+
+        if (pts.length >= 2) {
+            const simplified = [pts[0]];
+            const minStep = 0.03;
+            for (let i = 1; i < pts.length; i++) {
+                if (dist2(pts[i], simplified[simplified.length - 1]) >= minStep * minStep) {
+                    simplified.push(pts[i])
+                }
+            }
+            if (simplified.length >= 2) {
+                finalShape = { ...currentShape, points: simplified };
+            }
+        }
+    }
+
     if (currentShape.tool === 'line') {
         const line = normalizeLine(currentShape);