Here's a brief overview of the development process:

Creation Effort: It took about 10 hours to develop an alpha build. The key task was fine-tuning the AI with detailed custom instructions [all written in English] and background documents [also in English] about coin grading, particularly the Sheldon scale.

Here are some of the custom instructions I used:

Example Challenge and Solution: Initially, Numi struggled with identifying 's' mint marks on US coins. I updated the instructions to give it context about proof coins, and now it can better identify proof coins and give a PR grade rather than an MS grade.

Interface and Back-end: The app uses OpenAI's existing chat interface. There was no work done, or needed, to update the front-end user interface. The back-end customization involved only instructing the AI in natural language, without coding. It is possible to link the app to 3rd party APIs so the AI can interact with outside websites. One feature I will build is eBay integration so that users can pull up recently sold listing and see how much their coins [with the estimated grade] is worth.

Field Testing: I went to my local coin shop yesterday and tested the app with the shop owner. Results were mixed, with some estimates being in the ballpark while other estimates were off by as much as 20 points. I'm working on improving this by experimenting with lighting conditions and additional instructions.

. I am testing out various lighting conditions, adding new custom instructions, etc. I'm excited when OpenAI allows videos to be uploaded instead of just photos. Videos have a lot more info and may be the key to successful grading estimates.

Ability to follow up on conversations
One of the best things about Numi is it does much more than identify and grade coins. Users can ask follow-up questions to learn more about their coins. Users can follow up with questions such as:

Jefferson Nickel - 1980 S Proof

Lincoln Wheat Cent - 1948 D

Mexico One Peso - 1971

Another collector asked me how I built Numi and what I think is next. Below was my response:

I'd appreciate it if readers could send photos of their slabbed coins (8-10 photos, 4-5 per side, with the grade out of view for testing. Once I run the analysis, I'll report back to the reader and then they can give me the grade of the coin [if they know].

I would also love to get feedback from advanced/expert coin graders on Numi's current grading criteria. You can see the exact criteria in thisGoogle word doc and leave comments there.

Readers can contact me at justintsn10@gmail.com. I am also actively updating the app and posting results on my Instagram page for those who would like to follow my progress.

For more information on GPTs, see:
Introducing GPTs(https://openai.com/blog/introducing-gpts)

To read some related articles, see:
GPT is a New Type of Computer(https://embracingenigmas.substack.com/p/gpt-is-a-new-type-of-computer)
Opinion How AI could revolutionize banking and eliminate much of the risk(https://www.washingtonpost.com/opinions/2023/11/17/ai-big-banks-risks/)

for more about Justin Hinh, see:
https://justinhinh.webflow.io/

To read the earlier E-Sylum articles, see:
THE HISTORY OF THE COIN LIBRARY(https://www.coinbooks.org/esylum_v17n51a09.html)
NOTES FROM E-SYLUM READERS: OCTOBER 8, 2023 : AI-Generated Numismatic Images(https://www.coinbooks.org/v26/esylum_v26n41a14.html)