finalise table of contents

Author: burtenshaw

units/en/_toctree.yml

@@ -53,6 +53,10 @@
     title: "Module 2: GitHub Actions Integration"
   - local: unit3/slack-notification
     title: "Module 3: Slack Notification"
+  - local: unit3/build-mcp-server-solution-walkthrough
+    title: "Unit 3 Solution Walkthrough: Building a Pull Request Agent with MCP"
+  - local: unit3/certificate
+    title: "Get your certificate!"
   - local: unit3/conclusion
     title: "Unit 3 Conclusion"
 

units/en/unit3/NEXT_STEPS.md

@@ -0,0 +1,19 @@
+# Get your certificate!
+
+Well done! You've completed Unit 3 of the MCP course. Now it's time to take the exam to get your certificate.
+
+Below is a quiz to check your understanding of the unit. 
+
+<iframe
+	src="https://mcp-course-unit-3-quiz.hf.space"
+	frameborder="0"
+	width="850"
+	height="450"
+></iframe>
+
+<Tip>
+
+If you're struggling to use the quiz above, go to the space directly [on the Hugging Face Hub](https://huggingface.co/spaces/mcp-course/unit_3_quiz). If you find errors, you can report them in the space's [Community tab](https://huggingface.co/spaces/mcp-course/unit_3_quiz/discussions).
+
+</Tip>
+