#3178 Excel VBA Ollama Script

#3178 Can my Chrome browser execute a pyhon application on my PC without a server?

Short answer—sort-of, but with caveats

Chrome (or any modern browser) can interpret Python entirely inside the page, but it cannot launch a “normal” desktop Python script that has unrestricted access to your PC unless you give it help (e.g., via a helper app, local server, or extension).
Below are the practical ways to do it, what each can and can’t do, and when they make sense.

1. In-browser Python via WebAssembly

Technique	How it works	What you gain	Key limits
Pyodide / PyScript	CPython 3.x compiled to WebAssembly is downloaded with the page, runs in the browser sandbox. You embed `<script type="py"> … </script>` or call `pyodide.runPython(…)`.	No installation for the user, runs offline after first load, can call most Python libraries that are pure C/Python (NumPy, pandas, scikit-learn already work).	Sandbox: no raw disk, no direct sockets, no shell, heavy download (~5–15 MB compressed).
Brython, Skulpt, Transcrypt	Transpile Python to JavaScript.	Tiny payload, simple for teaching or UI glue.	Only a Python subset; no NumPy/SciPy; same sandbox as JS.

When to use it

Educational notebooks, data-vis dashboards, little AI demos.
Anything where browser-sandboxed file I/O (IndexedDB, fetch) is enough.

2. Chrome extension + Native Messaging host

You package a Chrome extension (HTML/JS UI).
You register a native-messaging host—a small JSON manifest that points to my_script.py on the PC.
The extension can send/receive JSON to that script over stdin/stdout.

Pros

Script runs with full OS privileges (read files, open sockets, call DLLs).
No “server” process to start manually; Chrome launches it on demand.

Cons

User must install both the extension and the native host (one-time OS-level install).
Only JSON messages—no raw pipes, limited 4 MiB per message.
Cross-platform packaging work.

Useful for tight integrations (e.g., automate CAD, open local files, control hardware) without an HTTP server.

3. Local helper app exposing a custom protocol

You ship a tiny Python (or Go/Rust) app that registers a custom URL scheme (myapp://), or listens on localhost only.
Chrome navigates to that scheme or makes fetch("http://127.0.0.1:port/...").

You said “without a server,” but a loopback-only helper is often the simplest secure path. Because it never leaves the machine, firewall rules are minimal and latency is nil.

4. Progressive Web App (PWA) that bundles Pyodide

If you want an “installable” feel: wrap a PyScript page as a PWA. Chrome lets users “install” it; afterwards it runs offline, still sandboxed.

What Chrome cannot do natively

Launch an arbitrary .py file on the file system by double-clicking a link.
Grant raw filesystem or network access to in-page code beyond the Web APIs (unless the user explicitly picks a file via the File System Access API, which still gives you a sandboxed handle).
Bypass OS security—the browser sandbox is intentional.

Choosing an approach

Need	Best option
Quick interactive demo, heavy numeric libs	Pyodide / PyScript
Teaching beginners, tiny footprint	Brython / Skulpt
Full OS access with no visible server window	Chrome extension + Native Messaging
Stand-alone desktop+web bundle	Electron or Tauri using a built-in Python runtime
Occasional automation on your own PC (no redistribution)	Just run the script in a terminal or VS Code—simplest of all

Opportunity for improvement (your innovation lens)

Build a “Pyodide-lite” loader that lazy-streams only the parts of the standard library actually used, cutting first-load size for spot demos.
Create a no-code packager: drag-and-drop a .py file and get a signed Chrome extension + native host installer, lowering the barrier for non-developers.
Offer a browser-first plugin framework where backend code is written once as standard Python but is auto-compiled to WebAssembly or registered as a native host depending on required permissions—letting the same code run in-sandbox or “break out” when needed.

Bottom line:
Yes, Chrome can run Python through WebAssembly today, and you can get full-privilege Python by pairing Chrome with a native host. What it cannot do is magically execute arbitrary local scripts out of the box—sandbox and user consent rules still apply. Pick the path that matches the level of OS access you truly need.

How do I activate VBA in excel?

Below are the two things most people mean when they ask to “activate VBA in Excel.”
Follow each section in order and you’ll be ready to record, write, and run macros.

1 Add the Developer tab (the gateway to VBA)

Excel on Windows (365 / 2016-2021)	Excel on macOS (365 / 2019-2021)
1. File ▸ Options ↳ Customize Ribbon	1. Excel ▸ Preferences ↳ Ribbon & Toolbar
2. In Main Tabs, tick Developer.	2. In the right-hand list, tick Developer.
3. Click OK. You now have a Developer tab on the ribbon.	3. Click Save. The Developer tab appears.

One-time action; Excel remembers the setting.

2 Make sure VBA macros are allowed

File ▸ Options ▸ Trust Center ▸ Trust Center Settings ▸ Macro Settings
Pick one of these (you can tighten it later):
- Disable all macros with notification – safest everyday choice; Excel shows an Enable Content button when you open a workbook that contains code.
- Enable VBA macros – only if you trust every file you open.

Security tip: Never enable macros globally if you routinely open files from email or the web; use the “notification” option instead.

Opening the Visual Basic Editor

Press Alt + F11 (Windows) or ⌥ Fn F11 / Option + F11 (Mac).
Or click Developer ▸ Visual Basic.

Inside the editor you can:

Insert ▸ Module – write or paste standard VBA code.
Insert ▸ UserForm – design a form.
Run ▸ Run Sub/UserForm (or F5) – execute.

Saving workbooks that contain code

File ▸ Save As ▸ Save as type: Excel Macro-Enabled Workbook (.xlsm)
(On Mac: File Format: Excel Macro-Enabled Workbook).

Excel blocks VBA if you store the file as plain .xlsx.

Quick troubleshooting checklist

Symptom	Fix
Developer tab missing again	Check that you saved Excel settings (some corporate PC images reset options at login).
Macros still disabled	Trust Center → Macro Settings may be overridden by Group Policy; contact IT.
Alt+F11 does nothing	The keyboard shortcut can be intercepted by add-ins; try the ribbon button.
“Can’t find project or library”	Open VB Editor → Tools ▸ References → locate the missing library or un-tick it.

Where to go next

Record Macro (Developer tab) – watch Excel generate VBA as you work and study the code.
Office VBA reference (Microsoft Learn) – full object model docs.
Immediate Window (Ctrl+G in the VB Editor) – quick one-line experiments.

Once the Developer tab is visible and macros are enabled, VBA is fully “activated” on your installation—no extra components or server required. Happy automating!

How can I test the following installed VBA script: """...https://www.reddit.com/r/ollama/comments/1d6c62o/excel_and_ollama/..."""?

Below is a practical, step-by-step checklist you can walk through to make sure the TestOllamaCompletion macro actually fires, reaches your local Ollama instance, and prints a response.

1 Confirm the prerequisites

Requirement	Quick check	Notes
Ollama running on the same PC	In a terminal run `ollama list` → you should see wizardlm2:7b with a status of “ready”.	If it isn’t listed, run `ollama pull wizardlm2:7b` and then `ollama serve` (or just restart Ollama Desktop).
Endpoint reachable	In a browser visit `http://localhost:11434` → you should at least get a “404 page not found” (shows port is listening).	Port number must match the `client.Open` line in your code.
JSON-Converter module imported	In the VB Editor, `Modules ▸ JsonConverter` should exist.	If not, download `JsonConverter.bas` from VBA-JSON and File ▸ Import File…
MSXML available	VB Editor → Tools ▸ References → tick Microsoft XML, v6.0 (or v3/4 if 6 isn’t installed).	If you stay with late binding (`CreateObject("MSXML2.ServerXMLHTTP")`) this isn’t strictly required, but early binding + compile-time checks are nicer.
`strKey` defined (only needed if your Ollama endpoint is protected)	Add `Const strKey = ""` at the top of the module (or remove the header line entirely for a local, unsecured Ollama).	Empty string is fine for local use; remote endpoints may need a token.

2 Paste/compile the code

Developer tab ▸ Visual Basic
Insert → Module → paste the code.
Optionally add Option Explicit at the very top and do Debug ▸ Compile VBA Project.
Fix any red-lines before moving on.

3 Run the test macro

Press Ctrl + G to bring up the Immediate window (so you can read Debug.Print).
Place the caret anywhere inside Sub TestOllamaCompletion
Press F5 (Run) or F8 (step through line-by-line).

If everything is wired correctly you should see something like:

Say, what's the big idea, pal? Scram before I fill you full of lead, see?

printed in the Immediate window.

4 Typical issues & quick fixes

Symptom	Likely cause	Fix
Compile error: “User-defined type not defined” on `Dictionary`	You copied early-binding sample but didn’t reference Microsoft Scripting Runtime.	Either tick the reference or switch back to late binding (`CreateObject("Scripting.Dictionary")`).
Run-time error ‘424’: Object required at `JsonConverter.ConvertToJson`	JsonConverter module missing or misspelled.	Import the module; make sure the `Function ConvertToJson` is visible.
Error 9001 “Failed to fetch” (raised from `Err.Raise`)	Ollama not listening, wrong port, or model hasn’t finished loading.	Verify `http://localhost:11434` and that `wizardlm2:7b` shows “running” in `ollama list`.
Response is empty	Returned JSON structure changed (older Ollama builds)	Inspect `client.responseText` in the Immediate window; adjust the path `completion("message")("content")` if the API changed.
“Connection refused”	Corporate firewall/AV blocks loopback HTTP.	Temporarily whitelist `Excel.exe` or switch to HTTPS on a different port.

5 Optional quality-of-life tweaks

Surface the answer in Excel rather than the VB Editor:

Range("B2").Value = response   'write to a cell
MsgBox response                'or pop up

Wrap network call in On Error… so Excel doesn’t halt abruptly.
Use early binding for MSXML (faster, IntelliSense):
```
Dim client As MSXML2.ServerXMLHTTP60
```

Parameterise the model so you can A/B test LLMs from the sheet:

response = Chat(promptMessage, userMessage, model:=Range("A1").Value)

Quick test script you can drop in after everything compiles

Sub SmokeTest()
    Dim r As String
    r = Chat("One-line system msg", "Say something short.", maxTokens:=30)
    MsgBox r, vbInformation, "Ollama quick test"
End Sub

If that dialog pops up with a sensible LLM reply, your VBA-to-Ollama pipeline is officially working. From there you can wire it into worksheets, buttons, or larger automation flows.

How do I execute the chat from the worksheet?

Below is a compact “cookbook” for wiring the Chat function to a worksheet so you can send a prompt from cells and see the LLM’s reply appear in another cell—no VB Editor window required.

1 Expose `Chat` as a worksheet function (UDF)

Your code already declares

Public Function Chat(userMessage As String, _
                     Optional promptMessage As String, _
                     Optional maxTokens As Integer = 1000, _
                     Optional model As String = "wizardlm2:7b") As String

Because it’s Public and lives in a standard module, Excel will recognise it as a User-Defined Function (UDF).
That means you can simply type a formula such as

=Chat($B$2, $A$2, 250, "wizardlm2:7b")

in any cell and Excel will call the API and return the string result.

Quick worksheet layout

Cell	Purpose	Example
A2	System / prompt message	You talk like a 1920s gangster.
B2	User message	What's the big idea, pal?
C2	Model name (optional)	wizardlm2:7b
D2	Formula that gets the answer	`=Chat(B2, A2, 250, C2)`

Important caveats

Excel may re-evaluate the formula frequently (every recalc, on open, etc.), causing repeated API hits.
Mitigation: switch Calculation to Manual (Formulas ▸ Calculation Options) or use the macro approach below.
If the call throws an error Excel will show #VALUE!. Wrap the call in a helper that swallows errors if you need a cleaner sheet.

2 Trigger the chat with a button (safer / cleaner)

If you prefer one-click execution (or want to avoid the continuous recalculation issue), wrap the call in a simple macro and bind it to a Form-Control button.

'Put this in the same module
Sub RunChatFromSheet()
    Dim sys As String, usr As String, mdl As String, resp As String
    
    sys = Range("A2").Value
    usr = Range("B2").Value
    mdl = Range("C2").Value        'blank is fine – Chat will use default
    
    On Error GoTo ChatErr
    resp = Chat(userMessage:=usr, promptMessage:=sys, model:=mdl)
    Range("D2").Value = resp
    Exit Sub
ChatErr:
    MsgBox "Chat failed: " & Err.Description, vbExclamation, "Chat error"
End Sub

Wire it up

Developer ▸ Insert ▸ Button (Form Control)
Draw the button on the sheet, choose RunChatFromSheet.
Rename the button caption to something like Get Response.

Now the API is only called when you press the button.

3 Automatic refresh when the user edits input cells (optional)

If you like “live” behaviour without explicit buttons but still want to avoid constant recalc, add a Worksheet_Change event:

'In the sheet’s code module (right-click sheet tab ▸ View Code)
Private Sub Worksheet_Change(ByVal Target As Range)
    'Trigger only when A2, B2 or C2 change
    If Not Intersect(Target, Range("A2:C2")) Is Nothing Then
        RunChatFromSheet
    End If
End Sub

4 Best-practice tweaks for production use

Topic	Suggestion
Long-running calls	Set `Application.ScreenUpdating = False` and `StatusBar` text inside the macro so Excel doesn’t look frozen.
Throttling / caching	Store the last prompt+user+model hash in a hidden sheet; skip the call if nothing changed.
Asynchronous pattern	For heavy models you can off-load the call to a VBA class that uses `DoEvents` in a loop, or call a small helper executable and poll; VBA itself has no built-in async/await.
Error logging	Write failures and timestamps to a log sheet so you know when the LLM or network misbehaved.
Security	Leave `strKey` empty for localhost; if you expose the endpoint beyond your PC, protect it and never hard-code a real key in a shared workbook.

Smoke-test in one minute

Make sure Ollama is running (ollama list shows wizardlm2:7b).
Fill A2/B2 as above.
Paste RunChatFromSheet into a module, press F5.
Response appears in D2 → success.

That’s all that’s required to “execute the chat from the worksheet.” Feel free to adapt the ranges, add a token counter, or loop over many rows for batch prompting.

I get #NAME? for =Chat(x,y,z)

#NAME? means Excel can’t find a name that you typed.
For a UDF that almost always means Excel doesn’t see the function or it’s trying to interpret the arguments as names instead of values / cell references.

1 Make sure Excel can “see” the Chat function

Check	How
*Function lives in a standard* module**	In the VB-Editor (Alt + F11) the code should be inside Module1, Module2, … – not inside “Sheet1 (Sheet1)” or “ThisWorkbook”.
Public, no `Option Private Module` above it	The first few lines of the module should look like: `Option Explicit` (optional) `Public Function Chat( … )`
Workbook is macro-enabled and macros are turned on	Save as .xlsm and enable macros when you open it.
Compile error-free	VB-Editor ▸ Debug ▸ Compile VBA Project – fix any red lines.

If any of those fail, Excel treats Chat as an unknown name → #NAME?.

2 Call it with real cell references or quoted text

When you write

=Chat(x,y,z)

Excel thinks x, y, and z are named ranges.
Unless you created names called x, y, and z, the result is #NAME?.

Correct patterns

Goal	Example formula	Explanation
Use worksheet cells	`=Chat(B2, A2, 250)`	B2 = user message, A2 = system prompt, 250 = max tokens
Pass literal text	`=Chat("What's up?", "You are a pirate.")`	Surround strings with quotes
Omit optional args	`=Chat(B2)`	Only user message; prompt uses default

Remember: Chat(promptMessage, userMessage, maxTokens, model)

3 Quick test checklist

In an empty sheet put:
- A2 → You talk like a 1920s gangster.
- B2 → What's the big idea, pal?

In C2 enter either of these:

As a formula using cells

=Chat(B2, A2)          'works if Chat is visible

Or hard-coded text

=Chat("What's the big idea, pal?", "You talk like a 1920s gangster.")

Press Enter.
If Chat is recognised, Excel shows the Ollama reply after a short pause.
If you still see #NAME?, go back to step 1.

4 Other causes (less common)

Cause	Symptom	Fix
Workbook open in Protected View	Yellow bar: “Enable Editing”	Click Enable Editing then Enable Content
Function marked `Private`	Compiles but not available in sheet	Change to `Public Function Chat`
You renamed the module but left code in a class module	VBE icon looks like a stack of boxes	Move the function to a standard module

tl;dr

#NAME? → Excel doesn’t recognise Chat or the arguments.
Ensure the code is in a public standard module, workbook is .xlsm, macros are enabled, and call it with real cell references or quoted strings – not bare letters x, y, z.

How can I add a parameter to chat that is the start of the output range?

What you can (and can’t) do in Excel

Goal	Works as a worksheet formula?	Works with a macro / button?
Return a value and let it “spill” into neighbouring cells	Yes (must return a Variant array). Excel itself decides where to put it.	Yes
*Tell a function which other* cell(s) to write to**	No – a UDF is forbidden to change anything except the cell that called it.	Yes – a Sub or Function called from VBA (button/menu) can write anywhere, because it runs outside the sheet-calculation sandbox.

So you have two practical patterns:

1 Keep it a worksheet function → return a spill array

If the only reason you wanted an “output start” argument was to have the reply occupy several cells, just return an array and let Excel spill it.

' --- New helper that returns one line per row ---------------
Public Function ChatLines(userMessage As String, _
                          Optional promptMessage As String, _
                          Optional delim As String = vbLf, _
                          Optional maxTokens As Long = 400, _
                          Optional model As String = "wizardlm2:7b") As Variant

    Dim txt As String
    txt = Chat(userMessage, promptMessage, maxTokens, model)   'call your existing routine
    
    ChatLines = Split(txt, delim)     'Excel 365 will spill down the sheet
End Function

Usage in the sheet (one formula, automatic spill):

=ChatLines(B2, A2)            'spills downward from the formula cell

If you prefer columns rather than rows, wrap the result in TRANSPOSE().

2 Let the caller tell VBA where to write → add a Range parameter

Create a wrapper Sub that accepts three ranges: system prompt, user prompt, and outputStart.
Because it runs as a macro (not as a sheet UDF) it can write anywhere.

' ---------- Put in a standard module ------------------------
Sub RunChatIntoRange(sysCell As Range, usrCell As Range, outputStart As Range, _
                     Optional maxTokens As Long = 1000, _
                     Optional model As String = "wizardlm2:7b")

    Dim reply As String, lines() As String, r As Long
    
    reply = Chat(usrCell.Value, sysCell.Value, maxTokens, model)
    
    'split into lines so we can write several cells if needed
    lines = Split(reply, vbLf)
    
    For r = LBound(lines) To UBound(lines)
        outputStart.Offset(r, 0).Value = lines(r)
    Next r
End Sub

Two easy ways to trigger it

Button on the sheet

Insert ▶ Button (Form Control)

Assign macro:

Sub ButtonChat()
    RunChatIntoRange Range("A2"), Range("B2"), Range("D2")   'edit addresses
End Sub

Worksheet event (auto-update when inputs change)

'Right-click the sheet tab ▸ View Code
Private Sub Worksheet_Change(ByVal Target As Range)
    If Not Intersect(Target, Range("A2:B2")) Is Nothing Then
        RunChatIntoRange Range("A2"), Range("B2"), Range("D2")
    End If
End Sub

Which option should you choose?

If you want…	Choose…
Simple “fire once” behaviour tied to a button	Option 2 (macro)
A formula that recalculates like any other, no buttons	Option 1 (spill-array function)
Multiple prompts in a table, one reply per row	Still Option 2 – loop down the table and write beside each row.

Either way, you don’t pass a “start-cell” argument into Chat itself when calling it from the worksheet; instead you (a) let Excel spill the array automatically or (b) run a wrapper macro that knows where to place the output.

What system instructions and user prompt do I need to get a list of numbers or text?

Below is a practical “recipe” you can drop straight into the promptMessage / userMessage parameters that your Chat function expects.

1 Pick the output format first

Format	Why choose it	How you’ll read it back in VBA
New-line–separated text	One formula in Excel can spill down a column with `Split(reply, vbLf)`	`lines = Split(reply, vbLf)`
CSV on one line	Handy when you want everything in a single cell, then `TextToColumns` later	`items = Split(reply, ",")`
Strict JSON array	Zero ambiguity; easy with the `JsonConverter` you already imported	`arr = ParseJson(reply)`

2 Template system instruction ( `promptMessage` )

# ROLE: system
You are a list generator.
Return **nothing except the requested list**.  
Rules:  
1. One item per line, no numbering or bullets.  
2. No blank lines, no explanations, no wrapping text.  
3. Preserve exact capitalisation / spelling of each item.

</details> <details> <summary><strong>b. JSON array (cleanest to parse)</strong></summary>

# ROLE: system
You are a JSON-only assistant.  
Return a single JSON value: an array of strings.  
No object wrapper, no extra keys, no comments, no markdown.

</details>

3 User-prompt patterns ( `userMessage` )

Wanted result	Example user prompt
List of numbers	`Give me the first 20 prime numbers.`
List of text items	`List 15 large U.S. airports by IATA code.`
List with a range	`Produce an integer list from 5 to 50, step 5.`
Mixed but still list	`Give 12 two-word phrases that describe teamwork.`

(If you chose JSON mode, don’t ask for numbering—just describe the items.)

4 Quick VBA call-example

Sub TestList()
    Dim sys$, usr$, reply$, items
    
    sys = "You are a JSON-only assistant. Return only a JSON array of integers."
    usr = "Give me the first 10 Fibonacci numbers."
    
    reply = Chat(userMessage:=usr, promptMessage:=sys, maxTokens:=150)
    
    '––– parse into a VBA array –––
    items = JsonConverter.ParseJson(reply)
    Debug.Print Join(items, ", ")
End Sub

5 Trouble-shooting tips

Symptom	Fix
Extra prose around the list	Strengthen the rules bullet (“Return nothing except…”).
Bullets or numbering sneaking in	Explicitly forbid them in the system text.
JSON wrapped in markdown fences	Add “No markdown” or “Do not wrap in triple back-ticks.”
Items spill into the next cell row	Use `Application.Clean` then `Split` on `vbLf`.

Take-away

System instruction = format contract (tell the model how to speak).
User prompt = content request (tell the model what to list).
Parse the reply exactly the way you specified—no guessing required.

Now that I have this installed and working, list and describe 15 excellent uses

Below are 15 high-impact ways you can exploit your new Excel + VBA + Ollama pipeline. Each idea is framed to fit a worksheet-centric workflow, so you can trigger it from formulas, buttons, or events exactly the way you’ve just configured.

Stand-up Requirement Explainer
Feed any NPR-7150.2D “SWE-###” reference in column A → return a plain-English summary in column B.
- Automates quick reviews during document prep; no external lookup needed.
One-click Checklist Generator
Select a standards section, press a macro button → spill a numbered V&V checklist into the next rows.
- Turns Excel into a lightweight process-compliance engine.
Context-aware Test-Case Builder
Give a software requirement sentence in A2, call ChatLines in B2 → get pre-formatted GIVEN/WHEN/THEN test steps.
- Cuts hours of manual test-design.
Data-dictionary Autofill
Point at a raw column header list → LLM writes descriptions, units, and valid ranges alongside each header.
- Excellent for ETL onboarding or when colleagues dump CSVs on you.
Rapid Traceability Matrix fill-in
Enter requirement IDs down column A and design-element IDs across row 1 → macro iterates cells, asks “does X satisfy Y?” and marks Y/N.
- Produces an auditable artefact in seconds.
Risk Phrase Normaliser
Paste free-text hazards → LLM rewrites each line into NASA 8719.13C-style phrasing and tags severity and likelihood.
- Instant consistency for safety reviews.
Instant Macro Recorder on Steroids
Type a plain-English instruction (“sort data by date, hide column F, make a chart”) → LLM returns VBA code into a module.
- Bridges the gap for teammates who don’t script.
Automated Meeting Minutes & Action Items
Drop a Teams transcript into one cell → spill key decisions, owners, and deadlines into a structured table.
- Turns chaotic notes into a task tracker without leaving Excel.
Prompt Library Cataloguer
Store your favourite system/user prompts in rows; the LLM tags each with use-case, tone, and ideal max-token count.
- Helps you organise and reuse high-value prompts across projects.
Inline Code Reviewer for Small Scripts
Paste a ≤200-line Python or C++ snippet → LLM comments on logic errors, edge cases, and improvement tips beside each line.
- Great for quick sanity checks before committing to Git.
Scenario-based Cost Estimator
Input BOM items and quantities → LLM pulls current ballpark prices (you feed them) and suggests low-budget alternates.
- Perfect for MAKER projects and quick proposal drafts.
Natural-language Database Queryer
Write “show all flights delayed > 30 min last week” in a cell → VBA passes it to LLM, which returns the SQL statement.
- Pairs beautifully with Excel’s native ODBC refresh.
Dynamic Learning Path Builder
Enter a topic (“Quantum annealing”) → LLM outputs a 4-week syllabus, resources, and incremental projects into adjacent rows.
- Adapts instantly for students with different backgrounds.
Marketing Copy Split-Tester
Feed product, tone, and character limit → spill five headline variants; another column scores likely CTR using a second LLM call.
- Rapid iteration without leaving the spreadsheet.
Cross-industry Innovation Scanner
Input a technology (e.g., “solid-state batteries”) → LLM lists 5 domains, 3 pain-points each, and one fresh solution idea per pain-point.
- Embeds your “topic → opportunity → improvement” prompt chain directly in Excel for fast ideation sessions.

Implementation Pointers

Formula-driven: wrap each use case in a spill-array UDF like =ChatLines(...) when you’re happy to accept recalculation on sheet open.
Macro-driven: for heavier prompts or multi-step jobs, put the logic in a Sub and launch it from a button or Worksheet_Change event.
Caching: store the last prompt hash in a hidden sheet to avoid repeat LLM calls on accidental recalcs.
Governance: log every request/response pair (timestamp, user, prompt, token count) to an “Audit” worksheet—handy for NASA process audits.

These patterns should cover everything from compliance work to creative ideation—exactly the breadth your projects demand. Enjoy pushing Excel far past spreadsheets!

From <https://chatgpt.com/> ChatGPT o3