Building a Better Title-Caser, Part 2: Using an Ollama Modelfile

Here I create a local titlecase model based on Mistral, using a local Ollama modelfile and a solid prompt.

Setup

import google.generativeai as genai
import ollama
from titlecase import titlecase

Create an Mistral-Based Model With an Ollama Modelfile

For better title casing, perhaps I can create an Ollama modelfile starting with a good model like mistral. I put this into tc.modelfile:

FROM mistral
PARAMETER temperature 0.1
PARAMETER num_ctx 512

# System prompt to specialize the model
SYSTEM """You are a title case expert. You follow these rules:
- Capitalize brand names correctly (e.g. iPhone, iPad)
- Keep acronyms in all caps (e.g. PDF, HTML)
- Hyphenated words have first letter of each word capitalized (e.g. E-Mail)
- Don't capitalize articles/conjunctions unless first word
Return only the properly title-cased text with no explanation."""

I created and used this model with:

ollama create titlecase -f tc.modelfile

I can see my new model with:

(uv) ~ % ollama list
NAME                  ID              SIZE      MODIFIED
titlecase:latest      255c41b01169    4.1 GB    14 minutes ago

I then defined a titlecase function with it:

def tc(s):
    return ollama.chat(model='titlecase', messages=[{
        'role': 'user',
        'content': f"Convert to title case: {s}"
    }])['message']['content'].strip()

tc("iphone and e-mail tips for pdfs")

[2025-02-16 09:25:08 - httpx:1025 - INFO] HTTP Request: POST http://127.0.0.1:11434/api/chat "HTTP/1.1 200 OK"





'iPhone and E-Mail Tips for PDFs'

tc("iphone and email tips for pdfs")

[2025-02-16 09:25:19 - httpx:1025 - INFO] HTTP Request: POST http://127.0.0.1:11434/api/chat "HTTP/1.1 200 OK"





'iPhone and Email Tips for PDFs'

The results are great. Of course this is just one test case.

Future Topics

• Compare the different title case functions more, using other test cases.
• See if I can get great performance out of another more lightweight local model.