RailsGPT

I've been playing around with using ChatGPT to answer my Rails-related questions. But I find that it often runs into problems. I decided to create a custom GPT to avoid them.

The problems are:

• ChatGPT often responds in a long tutorial-style format when really all I want is a short response.
• ChatGPT relies on using tutorials, guides, blog posts. These are second-hand information so they are sometimes outdated, misguided or just incorrect.
• ChatGPT doesn't have a great grasp of Rails internals. Especially bits that nobody else has written about. This makes it harder to build on lesser-known Rails functionality.

To combat these problems, I've taken the following steps:

• Prompted GPT to answer questions in the style I like.
• Upload all the Rails codebase into its "Knowledge", so it can always base its answers off the latest Rails code.

I've pasted the full prompt below if you'd like to have a read.

OpenAI put a limit on the number of files that users can upload to custom GPTs, so I wrote a script that compresses the Rails codebase into a few files. I've pasted the script below. Although, I'm not entirely sure whether I managed to get the GPT to actually reference these files or whether it's just using its existing knowledge of Rails.

Please email me if you have ideas for improving the GPT. And I hope you find this useful!

Here's a link to RailsGPT, the custom GPT for your Rails questions.

# Copy every file from ../rails, recursively, to the current directory.
# Rename the file to just the library it's in.
#
#   /actionpack/lib/action_controller.rb
#
#   to
#
#   actionpack.rb

require 'fileutils'

Dir.glob('../rails/**/*').each do |file|
  next if File.directory?(file)

  # Skip test files
  next if file =~ /_test\.rb$/

  # Skip files that are not ruby
  next unless file =~ /\.rb$/

  # Skip files that are not in the lib directory
  next unless file =~ /\/lib\//

  # Skip fi the file is less than N lines
  next if File.readlines(file).size < 200

  # Append the file to the library name
  # e.g.
  # /rails/actionpack/lib/action_controller.rb
  # goes to
  # actionpack.rb
  library_name = file.split('/')[2]

  File.open(library_name + '.rb', 'a') do |f|
    f.puts "\n\n"
    f.puts "# #{file}"

    f.puts File.read(file)
  end
end