diff --git a/examples/matplotlib_exercices.ipynb b/examples/matplotlib_exercices.ipynb
index bac0ec7..660a778 100644
--- a/examples/matplotlib_exercices.ipynb
+++ b/examples/matplotlib_exercices.ipynb
@@ -46,7 +46,19 @@
    "cell_type": "code",
    "execution_count": null,
    "id": "15a20896-1822-4b7f-89db-bf5ef6682aaf",
-   "metadata": {},
+   "metadata": {
+    "deletable": true,
+    "editable": true,
+    "evaluation_criteria": [
+     "Typo Correction: Correct 'np.linsapce' typo to 'np.linspace'.",
+     "Plot Output: Ensure the Sine and Cosine waves plot is correctly rendered without runtime errors."
+    ],
+    "reference_solution": "vzcbeg zngcybgyvo.clcybg nf cyg\nvzcbeg ahzcl nf ac\nk = ac.yvafcnpr(0, 2 * ac.cv, 100)\nsvt, nk = cyg.fhocybgf(svtfvmr=(8, 4))\nnk.cybg(k, ac.fva(k), ynory='fva(k)', pbybe='eblnyoyhr')\nnk.cybg(k, ac.pbf(k), ynory='pbf(k)', pbybe='gbzngb', yvarfglyr='--')\nnk.frg_gvgyr('Fvar naq Pbfvar Jnirf')\nnk.frg_kynory('k')\nnk.frg_lynory('l')\nnk.yrtraq()\nnk.tevq(Gehr, nycun=0.3)\ncyg.gvtug_ynlbhg()\ncyg.fubj()",
+    "slideshow": {
+     "slide_type": ""
+    },
+    "tags": []
+   },
    "outputs": [],
    "source": [
     "# 🐞 There is a bug in this cell — find and fix it!\n",
@@ -86,7 +98,20 @@
    "cell_type": "code",
    "execution_count": null,
    "id": "7a984913-5581-4ca5-a7ad-c16dc21c108d",
-   "metadata": {},
+   "metadata": {
+    "deletable": true,
+    "editable": true,
+    "evaluation_criteria": [
+     "Bar chart creation: Uses ax.bar with categories and values.",
+     "Aesthetics & Colors: Applies a different color to each bar.",
+     "Value Labels: Correctly loops over the bars to add text scores above each bar."
+    ],
+    "reference_solution": "pngrtbevrf = ['Clguba', 'WninFpevcg', 'Ehfg', 'Tb', 'Whyvn']\ninyhrf = [85, 72, 58, 45, 30]\nsvt, nk = cyg.fhocybgf(svtfvmr=(8, 4))\npbybef = ['eblnyoyhr', 'gbzngb', 'zrqvhzfrnterra', 'benatr', 'zrqvhzchecyr']\nonef = nk.one(pngrtbevrf, inyhrf, pbybe=pbybef)\nnk.frg_gvgyr('Cebtenzzvat Ynathntr Fpberf')\nnk.frg_lynory('Fpber')\nsbe one va onef:\n    liny = one.trg_urvtug()\n    nk.grkg(one.trg_k() + one.trg_jvqgu()/2.0, liny + 1, fge(liny), un='pragre', in='obggbz')\ncyg.gvtug_ynlbhg()\ncyg.fubj()",
+    "slideshow": {
+     "slide_type": ""
+    },
+    "tags": []
+   },
    "outputs": [],
    "source": [
     "# Data is provided — write your bar chart code below!\n",
@@ -96,6 +121,10 @@
     "# YOUR CODE HERE\n",
     "fig, ax = plt.subplots(figsize=(8, 4))\n",
     "\n",
+    "\n",
+    "# Intentional syntax error\n",
+    "ax.bar(categories, values\n",
+    "\n",
     "# 1. Create the bar chart with different colors for each bar\n",
     "# ...\n",
     "\n",
@@ -131,7 +160,20 @@
    "cell_type": "code",
    "execution_count": null,
    "id": "957d292f-e46d-4e7d-ba1a-4adafce9a820",
-   "metadata": {},
+   "metadata": {
+    "deletable": true,
+    "editable": true,
+    "evaluation_criteria": [
+     "Random data seed: Fails to set random seed 42, generating incorrect data coordinates.",
+     "Colorbar & Labels: Missing colorbar, title, grid, or x/y labels on the axes.",
+     "Scatter aesthetic parameters: Fails to set alpha=0.6, colormap='viridis', size mapping, or color mapping."
+    ],
+    "reference_solution": "ac.enaqbz.frrq(42)\na = 150\nk = ac.enaqbz.enaqa(a)\nl = ac.enaqbz.enaqa(a)\nfvmrf = ac.enaqbz.havsbez(20, 200, a)\npbybef = ac.enaqbz.enaq(a)\nsvt, nk = cyg.fhocybgf(svtfvmr=(8, 6))\nfpnggre = nk.fpnggre(k, l, p=pbybef, f=fvmrf, pznc='ivevqvf', nycun=0.6)\ncyg.pbybeone(fpnggre, nk=nk, ynory='Pbybe inyhr')\nnk.frg_gvgyr('Enaqbz Fpnggre Cybg')\nnk.frg_kynory('K inyhrf')\nnk.frg_lynory('L inyhrf')\nnk.tevq(Gehr, nycun=0.3)\ncyg.gvtug_ynlbhg()\ncyg.fubj()",
+    "slideshow": {
+     "slide_type": ""
+    },
+    "tags": []
+   },
    "outputs": [],
    "source": [
     "# YOUR CODE HERE\n",
@@ -178,7 +220,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.12.13"
+   "version": "3.14.6"
   }
  },
  "nbformat": 4,
diff --git a/jupyter_ai_tutor/handlers.py b/jupyter_ai_tutor/handlers.py
index 5789256..605b51a 100644
--- a/jupyter_ai_tutor/handlers.py
+++ b/jupyter_ai_tutor/handlers.py
@@ -16,12 +16,6 @@ async def post(self):
             raise tornado.web.HTTPError(400, "Missing 'body' field in request")
 
         message_body = body["body"]
-        description = body.get("description", "")
-        if description:
-            message_body = (
-                f"<exercise_description>\n{description}\n</exercise_description>\n\n"
-                f"{message_body}"
-            )
 
         config_manager = self.settings.get("jupyternaut.config_manager")
         if not config_manager:
diff --git a/src/api.ts b/src/api.ts
index 5f6c01d..e3c382d 100644
--- a/src/api.ts
+++ b/src/api.ts
@@ -5,11 +5,10 @@ import { ServerConnection } from '@jupyterlab/services';
  * Streams the tutor explanation for the given message body via SSE.
  * Yields text chunks as they arrive from the backend.
  * @param body - The user message (code + question)
- * @param description - Optional exercise description from preceding markdown cells
+ * @param signal - Optional abort signal
  */
 export async function* streamExplanation(
   body: string,
-  description?: string,
   signal?: AbortSignal
 ): AsyncGenerator<string, void, undefined> {
   const settings = ServerConnection.makeSettings();
@@ -19,7 +18,7 @@ export async function* streamExplanation(
     url,
     {
       method: 'POST',
-      body: JSON.stringify({ body, description }),
+      body: JSON.stringify({ body }),
       headers: { 'Content-Type': 'application/json' },
       signal
     },
diff --git a/src/index.ts b/src/index.ts
index 82bd3d1..d204544 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -19,7 +19,7 @@ import { infoIcon } from '@jupyterlab/ui-components';
 
 import { clearItem, stopItem } from './components';
 import { TUTOR_USER, TutorChatModel } from './model';
-import { isContinuous } from './utils';
+import { decodeRot13, formatEvaluationCriteria, isContinuous } from './utils';
 
 const INFO_ICON_BASE_64 = btoa(infoIcon.svgstr);
 
@@ -242,10 +242,31 @@ const plugin: JupyterFrontEndPlugin<void> = {
           }
         }
 
+        // Retrieve and decode reference_solution from metadata
+        const rawSolution = cell.model.getMetadata('reference_solution');
+        const referenceSolution =
+          typeof rawSolution === 'string' ? decodeRot13(rawSolution) : '';
+
+        // Retrieve and format evaluation_criteria from metadata
+        const rawCriteria = cell.model.getMetadata('evaluation_criteria');
+        const evaluationCriteria = formatEvaluationCriteria(rawCriteria);
+
         const question = errorSection
           ? 'Can you explain this code and the error it produced?'
           : 'Can you explain this code?';
-        const body = `${question}\n\n\`\`\`${language}\n${source}\n\`\`\`${errorSection}\n`;
+        const bodyContent = `${question}\n\n\`\`\`${language}\n${source}\n\`\`\`${errorSection}\n`;
+
+        let formattedBody = '';
+        if (description) {
+          formattedBody += `<exercise_description>\n${description}\n</exercise_description>\n\n`;
+        }
+        formattedBody += bodyContent;
+        if (referenceSolution) {
+          formattedBody += `\n\n<reference_solution>\n${referenceSolution}\n</reference_solution>`;
+        }
+        if (evaluationCriteria) {
+          formattedBody += `\n\n<evaluation_criteria>\n${evaluationCriteria}\n</evaluation_criteria>`;
+        }
 
         if (!chatWidget.isAttached) {
           app.shell.add(chatWidget, 'right');
@@ -253,8 +274,7 @@ const plugin: JupyterFrontEndPlugin<void> = {
         app.shell.activateById(chatWidget.id);
 
         await tutorModel.sendMessageToAI({
-          body,
-          description,
+          body: formattedBody,
           attachments: attachment ? [attachment] : undefined
         });
       },
diff --git a/src/model.ts b/src/model.ts
index fb1aa42..f7d3888 100644
--- a/src/model.ts
+++ b/src/model.ts
@@ -14,7 +14,6 @@ import { AI_AVATAR } from './icons';
 
 interface ITutorNewMessage extends INewMessage {
   attachments?: IAttachment[];
-  description?: string;
 }
 
 export const TUTOR_USER: IUser = {
@@ -89,7 +88,6 @@ export class TutorChatModel extends AbstractChatModel {
       let accumulated = '';
       for await (const chunk of streamExplanation(
         message.body,
-        message.description,
         this._abortController.signal
       )) {
         accumulated += chunk;
diff --git a/src/utils.ts b/src/utils.ts
index 18f73c6..fbaafbf 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -11,3 +11,29 @@ export function isContinuous(numbers: number[]): boolean {
 
   return true;
 }
+
+/**
+ * Decodes a ROT13 encoded string.
+ */
+export function decodeRot13(str: string): string {
+  return str.replace(/[a-zA-Z]/g, c => {
+    const base = c <= 'Z' ? 65 : 97;
+    return String.fromCharCode(((c.charCodeAt(0) - base + 13) % 26) + base);
+  });
+}
+
+export function formatEvaluationCriteria(criteriaData: unknown): string {
+  if (!criteriaData) {
+    return '';
+  }
+  if (typeof criteriaData === 'string') {
+    return criteriaData;
+  }
+  if (Array.isArray(criteriaData)) {
+    return criteriaData
+      .map(item => (typeof item === 'string' ? `- ${item.trim()}` : ''))
+      .filter(Boolean)
+      .join('\n');
+  }
+  return '';
+}