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+---
+slug: echokit-30-days-day-14-personality
+title: "Day 14: Give EchoKit a New Personality with System Prompt | The First 30 Days with EchoKit"
+tags: [echokit30days]
+---
+
+Over the past few days, we explored how EchoKit connects to different LLM providers — [OpenAI](https://echokit.dev/docs/dev/echokit-30-days-day-9-chatgpt), [OpenRouter](https://echokit.dev/docs/dev/echokit-30-days-day-10-openrouter), [Groq](https://echokit.dev/docs/dev/echokit-30-days-day-11-groq), [Grok](https://echokit.dev/docs/dev/echokit-30-days-day-12-grok) and even fully [local models like Qwen3](https://echokit.dev/docs/dev/echokit-30-days-day-13-local-llm).
+
+But switching the model only decides *how smart* EchoKit is.
+
+Today, we’re doing something much more fun:
+we’re changing **who EchoKit is.**
+
+With one simple system prompt, you can turn EchoKit into a cat, a coach, a tired office worker, a sarcastic companion, or a dramatic Shakespeare actor.
+No code. No firmware change. Just one text block in your configuration.
+
+Let’s make EchoKit come alive.
+
+
+## What Is a System Prompt, and Why Does It Matter?
+
+A *system prompt* is the personality, behavior guideline, and “soul” you give your LLM.
+
+It defines:
+
+* How EchoKit speaks
+* What role it plays
+* Its tone and attitude
+* How it should respond in different situations
+
+
+System prompt is incredibly powerful.
+Change it, and the *same* model can behave like a completely different agent.
+
+
+## Where the System Prompt Lives in EchoKit
+
+In your `config.toml`, under the `[[llm.sys_prompts]]` section, you’ll find:
+
+```toml
+[[llm.sys_prompts]]
+role = "system"
+content = """
+  (your prompt goes here)
+"""
+```
+
+Just edit this text, save the file, and restart the EchoKit server.
+
+If your WiFi and EchoKit server didn't change, press the rst button on the device to make the new system prompt take effect.
+
+
+## 5 Fun and Hilarious Prompt Ideas You Can Try Today
+
+Below are ready-to-use system prompts.
+Copy, paste, enjoy.
+
+**1. The “Explain Like I’m Five” Tutor**
+
+```
+You explain everything as if you're teaching a five-year-old. 
+Simple, patient, cute, and crystal clear.
+```
+
+**2. The Shakespearean AI**
+
+```
+You speak like a dramatic Shakespeare character, 
+as if every mundane question is a matter of cosmic destiny.
+```
+
+
+**3. The Confused but Hardworking AI Intern**
+
+```
+You are a slightly confused intern who tries extremely hard. 
+Sometimes you misunderstand things in funny ways, but you stay cheerful.
+```
+
+**4. The Cat That Doesn’t Understand Human Problems**
+
+```
+You are a cat. 
+You interpret all human activities through a cat’s perspective. 
+Add 'meow' occasionally. 
+You don't truly understand technology.
+```
+
+**5. The Absurd Metaphor Philosopher**
+
+```
+You must include at least one ridiculous metaphor in every reply. 
+Be philosophical but humorous.
+```
+
+Have fun — EchoKit becomes a completely different creature depending on what you choose.
+
+---
+
+## **Prompt Debugging Tips**
+
+If your character “breaks,” try adding:
+
+* “Stay in character.”
+* “Keep responses short.”
+* “If unsure, make up a fun explanation.”
+* “Use a consistent tone.”
+
+Prompt tuning is an art. A few careful sentences can reshape the entire interaction.
+
+
+Try giving your EchoKit different personalities now.
+
+Want to explore more or share what you’ve built?
+
+* Join the **[EchoKit Discord](https://discord.gg/Fwe3zsT5g3)**
+
+Ready to get your own EchoKit?
+
+* **EchoKit Box →** [https://echokit.dev/echokit_box.html](https://echokit.dev/echokit_box.html)
+* **EchoKit DIY Kit →** [https://echokit.dev/echokit_diy.html](https://echokit.dev/echokit_diy.html)
+
+**Start building your own voice AI agent today.**