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What Are Custom Assistants?

Custom assistants let you give the AI a set of instructions it will follow in every AI Chat response. Instead of repeating “always answer concisely” or “respond in Spanish” in each message, you write those instructions once in an assistant, activate it, and the AI behaves that way automatically. You can create multiple assistants and switch between them — for example one for data analysis and another for drafting reports.

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How to Create an Assistant

1

Open Settings

Click the Settings icon (gear) in the top-right corner of the add-in.
2

Open the Assistants page

Scroll to the Assistants row and click Manage.
3

Create a new assistant

Click Create assistant at the top of the page.
4

Give it a name

Enter a short name that describes its purpose — for example Data Analyst or Formal Spanish.
5

Write your instructions

In the Instructions field, describe how the AI should behave. Be as specific as you need — see the examples below.
6

Save

Click Save. The assistant is now created and set as active.

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How to Switch Between Assistants

Switching is done from the same Assistants page where you manage them.
  1. Open Settings → Assistants → Manage.
  2. Tap any assistant in the list to make it active — a checkmark appears next to the active one.
  3. Tap the active assistant again to deselect it and go back to Default (no custom instructions).
  4. To switch to a different assistant, simply tap another one.
The active assistant is remembered across sessions. Every AI Chat message you send will use its instructions until you change it.

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Editing and Deleting Assistants

On the Assistants page:
  • Click the pencil icon next to an assistant to edit its name or instructions.
  • Click the trash icon to delete it. You will be asked to confirm before it is removed.

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Writing Effective Instructions

Instructions tell the AI exactly how to behave. The clearer and more specific they are, the better the results.

Tone and style

“Always answer concisely. Use bullet points and avoid long paragraphs.”

Output format

“When suggesting formulas, always show the full formula and a one-line explanation.”

Language

“Always respond in Spanish, regardless of the language of my question.”

Domain focus

“You are a financial analyst. Frame all answers around budgeting and forecasting.”

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More instruction examples

Tone:
  • “Be concise. Prefer short, direct answers.”
  • “Explain your reasoning step by step before giving the final answer.”
Output and formatting:
  • “Always return results as a markdown table when listing data.”
  • “When you suggest an Excel formula, wrap it in backticks and explain each argument.”
Content rules:
  • “Assume the first row of any selected range is a header.”
  • “When analyzing data, always point out the top and bottom values.”
Language:
  • “Respond in French. Maintain a professional register.”
  • “Translate all summaries into Japanese.”

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Frequently Asked Questions

There is no fixed limit — you can create as many assistants as you need.
No, only one assistant is active at a time. To switch, tap a different assistant in the list. To use no custom instructions, tap the active assistant again to deselect it.
The active assistant is automatically cleared and the AI reverts to Default behavior.
Assistants apply to the AI Chat. The instructions you write are passed to the AI alongside your message every time you send a chat request. GPT functions in cells are not affected.
Yes — instructions can be up to 2,000 characters. The character count is shown below the input field as you type.

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Next Steps

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