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.