Klee (kleː)

Find similarities and differences in object APIs by tracking patterns.

See where your objects' methods are following common patterns and where they are not.

Installation

Install the gem and add to the application's Gemfile by executing:

$ bundle add klee

If bundler is not being used to manage dependencies, install the gem by executing:

$ gem install klee

Usage

Sort methods based upon patterns

class Something
  # define methods that might match some of the patterns
end

patterns = Klee.patterns do
  prefix("has_")
  prefix("verify_")
  infix("_in_")
  suffix("_value?")
end

gestalt = Klee[Something.new, patterns: patterns]
gestalt.trace(threshold: 6) # threshold for levenshtein distance between unusual method names
puts gestalt.plot
gestalt.trace(threshold: 9) # clear the plot and trace again
puts gestalt.plot
puts gestalt["unusual"] # unusual method names

Find hidden concepts based upon word repetition

class Something
  # define methods that have common word parts
end

concept = Klee.object_concepts(Something)

concept[4] #=> Set of words that appear at least 4 times
concept[2] #=> larger Set of words that appear at least 2 times

filtered = Klee.object_concepts(Something, modifiers: %i[fill_in_ hover_over_ _message])
filtered[4] #=> Set of concepts excluding any common modifiers

Scan a codebase for domain concepts

Discover hidden vocabulary across your entire codebase by analyzing class and method names.

codebase = Klee.scan("app/**/*.rb", "lib/**/*.rb")

# See all concepts ranked by frequency
codebase.concepts.rank
# => {
#   "user" => { classes: Set["User", "UserSession"], methods: Set["current_user", "find_user"] },
#   "account" => { classes: Set["Account", "AccountManager"], methods: Set["account_balance"] },
#   ...
# }

# Drill into a specific concept
codebase.concepts[:account]
# => { classes: Set["Account", "AccountManager"], methods: Set["account_balance", "close_account"] }

# Filter noise with ignore list and threshold
codebase = Klee.scan("app/**/*.rb",
                     ignore: %i[new create get set find all],
                     threshold: 3)

Find collaborator clusters

Discover which objects frequently work together across your codebase.

codebase = Klee.scan("app/**/*.rb", threshold: 3)

# Pairwise co-occurrence (which objects appear together in files)
codebase.collaborators.pairs
# => { ["account", "user"] => 15, ["session", "user"] => 12, ... }

# Method-level co-occurrence (tighter coupling)
codebase.collaborators.pairs(scope: :method)
# => { ["account", "user"] => 8, ... }

# What collaborates with a specific object
codebase.collaborators.for(:user)
# => { "account" => 15, "session" => 12, "order" => 5 }

# Derived clusters (connected components)
codebase.collaborators.clusters
# => [Set["user", "account", "session"], Set["order", "payment", "invoice"]]

MCP Server for Claude Code

Expose klee's vocabulary analysis to Claude Code or other MCP clients.

# Install the mcp gem (optional dependency)
gem install mcp

# Run the server
klee-mcp

Configure Claude Code in ~/.claude.json:

{
  "mcpServers": {
    "klee": {
      "command": "klee-mcp"
    }
  }
}

Available tools:

discover_vocabulary - Extract domain language from a codebase
find_concept_clusters - Identify groups of related concepts
explore_concept - Deep-dive into a specific concept
find_collaborators - Find objects that work together
check_naming_consistency - Detect naming pattern deviations
codebase_summary - High-level vocabulary overview

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and the created tag, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/saturnflyer/klee. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

License

The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the Klee project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.

klee

Runtime