diff --git a/README.md b/README.md
index 300e2b0..67c5680 100644
--- a/README.md
+++ b/README.md
@@ -101,7 +101,7 @@ puts document.child?                   # is this a highlight/note of another doc
 
 # Check location
 puts document.in_new?
-puts document.in_later?  
+puts document.in_later?
 puts document.in_archive?
 
 # Check category
@@ -142,6 +142,32 @@ document = client.create_document(document: document_create)
 documents = client.create_documents(documents: [document_create1, document_create2])
 ```
 
+## Command Line Interface
+
+This gem includes a `readwise` command-line tool for quickly sending HTML content to Readwise Reader.
+
+First, set your API token:
+```bash
+export READWISE_API_KEY=your_token_here
+```
+
+Then use the CLI to send HTML files:
+```bash
+# Basic usage
+readwise document create --html-file content.html
+readwise document create --url https://datatracker.ietf.org/doc/html/rfc2324
+
+# Short form flag
+readwise document create -f content.html
+
+# With options
+readwise document create --html-file content.html --title="My Article" --location=later
+
+# See all available options
+readwise --help
+readwise document create --help
+```
+
 ## Development
 
 After checking out the repo, run `bin/setup` to install dependencies. Then, run `bundle exec rspec` to run the tests. You can also run `bin/console` for an interactive prompt that will allow you to experiment.
diff --git a/exe/readwise b/exe/readwise
new file mode 100755
index 0000000..58f7d30
--- /dev/null
+++ b/exe/readwise
@@ -0,0 +1,7 @@
+#!/usr/bin/env ruby
+
+require 'bundler/setup'
+require 'readwise'
+require 'readwise/cli'
+
+Readwise::CLI.start
diff --git a/lib/readwise/cli.rb b/lib/readwise/cli.rb
new file mode 100644
index 0000000..7ac186a
--- /dev/null
+++ b/lib/readwise/cli.rb
@@ -0,0 +1,64 @@
+require_relative 'cli/base_command'
+require_relative 'cli/command_registry'
+
+module Readwise
+  class CLI
+    def self.start(args = ARGV)
+      new.start(args)
+    end
+
+    def start(args)
+      if args.empty?
+        show_help
+        exit 1
+      end
+
+      if args.first == '--help' || args.first == '-h'
+        show_help
+        return
+      end
+
+      resource = args.shift&.downcase
+      action = args.shift&.downcase
+
+      unless resource && action
+        puts "Error: Resource and action are required"
+        puts "Usage: readwise <resource> <action> [options] [arguments]"
+        puts "Run 'readwise --help' for more information"
+        exit 1
+      end
+
+      command_class = CommandRegistry.find(resource, action)
+      unless command_class
+        puts "Error: Unknown command '#{resource} #{action}'"
+        puts "Run 'readwise --help' to see available commands"
+        exit 1
+      end
+
+      command = command_class.new
+      command.execute(args)
+    rescue => e
+      puts "Unexpected error: #{e.message}"
+      exit 1
+    end
+
+    private
+
+    def show_help
+      puts <<~HELP
+        Usage: readwise <resource> <action> [options] [arguments]
+
+        Available commands:
+          document create --html-file <file>    Send HTML content to Readwise Reader
+
+        Global options:
+          -h, --help               Show this help message
+
+        Examples:
+          readwise document create --html-file content.html --title="My Article"
+          readwise document create -f content.html --title="My Article"
+          readwise document create --help
+      HELP
+    end
+  end
+end
diff --git a/lib/readwise/cli/base_command.rb b/lib/readwise/cli/base_command.rb
new file mode 100644
index 0000000..73614ac
--- /dev/null
+++ b/lib/readwise/cli/base_command.rb
@@ -0,0 +1,105 @@
+require 'optparse'
+
+module Readwise
+  class CLI
+    class BaseCommand
+      def initialize
+        @options = {}
+      end
+
+      def execute(args)
+        parse_options(args)
+        validate_arguments(args)
+        run(args)
+      rescue OptionParser::InvalidOption => e
+        puts "Error: #{e.message}"
+        show_help
+        exit 1
+      rescue ArgumentError => e
+        puts "Error: #{e.message}"
+        exit 1
+      end
+
+      private
+
+      attr_reader :options
+
+      def parse_options(args)
+        parser = create_option_parser
+        parser.parse!(args)
+      end
+
+      def create_option_parser
+        OptionParser.new do |opts|
+          opts.banner = banner
+          opts.separator ""
+          opts.separator description if description
+          opts.separator ""
+          opts.separator "Options:"
+
+          add_options(opts)
+
+          opts.on("-h", "--help", "Show this help message") do
+            show_help
+            exit
+          end
+        end
+      end
+
+      def show_help
+        puts create_option_parser.help
+      end
+
+      def get_api_client
+        token = ENV['READWISE_API_KEY']
+        unless token
+          puts "Error: READWISE_API_KEY environment variable is not set"
+          exit 1
+        end
+
+        Readwise::Client.new(token: token)
+      end
+
+      def read_file(file_path)
+        unless File.exist?(file_path)
+          puts "Error: File '#{file_path}' not found"
+          exit 1
+        end
+
+        File.read(file_path)
+      end
+
+      def handle_api_error(&block)
+        yield
+      rescue Readwise::Client::Error => e
+        puts "API Error: #{e.message}"
+        exit 1
+      rescue => e
+        puts "Unexpected error: #{e.message}"
+        exit 1
+      end
+
+      # Override these methods in subclasses
+
+      def banner
+        "Usage: readwise"
+      end
+
+      def description
+        nil
+      end
+
+      def add_options(opts)
+        # Override in subclasses to add specific options
+      end
+
+      def validate_arguments(args)
+        # Override in subclasses to validate arguments
+      end
+
+      def run(args)
+        raise NotImplementedError, "Subclasses must implement #run"
+      end
+    end
+  end
+end
diff --git a/lib/readwise/cli/command_registry.rb b/lib/readwise/cli/command_registry.rb
new file mode 100644
index 0000000..1137059
--- /dev/null
+++ b/lib/readwise/cli/command_registry.rb
@@ -0,0 +1,24 @@
+module Readwise
+  class CLI
+    class CommandRegistry
+      @commands = {}
+
+      def self.register(resource, action, command_class)
+        key = "#{resource}:#{action}"
+        @commands[key] = command_class
+      end
+
+      def self.find(resource, action)
+        key = "#{resource}:#{action}"
+        @commands[key]
+      end
+
+      def self.all_commands
+        @commands.keys.map { |key| key.split(':') }
+      end
+    end
+  end
+end
+
+# Register available commands
+require_relative 'document/create_command'
diff --git a/lib/readwise/cli/document/create_command.rb b/lib/readwise/cli/document/create_command.rb
new file mode 100644
index 0000000..a68a38f
--- /dev/null
+++ b/lib/readwise/cli/document/create_command.rb
@@ -0,0 +1,128 @@
+require_relative '../base_command'
+
+module Readwise
+  class CLI
+    module Document
+      class CreateCommand < BaseCommand
+        CATEGORIES = %w[article email rss highlight note pdf epub tweet video].freeze
+        def banner
+          "Usage: readwise document create [options]"
+        end
+
+        def description
+          "Sends HTML content to Readwise Reader API"
+        end
+
+        def add_options(opts)
+          opts.on("-f", "--html-file=FILE", "HTML file path") do |file|
+            options[:file] = file
+          end
+
+          opts.on("--title=TITLE", "Document title") do |title|
+            options[:title] = title
+          end
+
+          opts.on("--author=AUTHOR", "Document author") do |author|
+            options[:author] = author
+          end
+
+          opts.on("-u", "--url=URL", "Source URL (defaults to https://example.com/<filename>)") do |url|
+            options[:url] = url
+          end
+
+          opts.on("--summary=SUMMARY", "Document summary") do |summary|
+            options[:summary] = summary
+          end
+
+          opts.on("--notes=NOTES", "Personal notes") do |notes|
+            options[:notes] = notes
+          end
+
+          opts.on("--location=LOCATION", "Document location: new, later, archive, feed (default: new)") do |location|
+            unless %w[new later archive feed].include?(location)
+              puts "Error: Invalid location. Must be one of: new, later, archive, feed"
+              exit 1
+            end
+            options[:location] = location
+          end
+
+          opts.on("--category=CATEGORY", "Document category: #{CATEGORIES.join(', ')}") do |category|
+            unless CATEGORIES.include?(category)
+              puts "Error: Invalid category. Must be one of: #{CATEGORIES.join(', ')}"
+              exit 1
+            end
+            options[:category] = category
+          end
+
+          opts.on("--tags=TAGS", "Comma-separated list of tags") do |tags|
+            options[:tags] = tags.split(',').map(&:strip)
+          end
+
+          opts.on("--image-url=URL", "Image URL") do |image_url|
+            options[:image_url] = image_url
+          end
+
+          opts.on("--published-date=DATE", "Published date (ISO 8601 format)") do |date|
+            options[:published_date] = date
+          end
+
+          opts.on("--[no-]clean-html", "Clean HTML (default: true)") do |clean|
+            options[:should_clean_html] = clean
+          end
+
+          opts.on("--saved-using=SOURCE", "Saved using source (default: cli)") do |source|
+            options[:saved_using] = source
+          end
+        end
+
+        def validate_arguments(args)
+          unless options[:file] || options[:url]
+            puts "Error: File path or URL is required"
+            show_help
+            exit 1
+          end
+        end
+
+        def run(args)
+          html_file = options[:file]
+          html_content = read_file(html_file) if html_file
+
+          document_params = build_document_params(html_content, html_file)
+
+          handle_api_error do
+            client = get_api_client
+            document_create = Readwise::DocumentCreate.new(**document_params)
+            document = client.create_document(document: document_create)
+
+            puts "Document created successfully!"
+            puts "ID: #{document.id}"
+            puts "Title: #{document.title}"
+            puts "Location: #{document.location}"
+            puts "URL: #{document.url}" if document.url
+          end
+        end
+
+        private
+
+        def build_document_params(html_content, html_file)
+          document_params = {
+            html: html_content,
+            location: options[:location] || 'new',
+            should_clean_html: options.key?(:should_clean_html) ? options[:should_clean_html] : true,
+            saved_using: options[:saved_using] || 'cli',
+            url: options[:url] || "https://example.com/#{File.basename(html_file)}"
+          }
+
+          [:title, :author, :summary, :notes, :category, :tags, :image_url, :published_date].each do |key|
+            document_params[key] = options[key] if options[key]
+          end
+
+          document_params
+        end
+      end
+    end
+  end
+end
+
+# Register this command
+Readwise::CLI::CommandRegistry.register('document', 'create', Readwise::CLI::Document::CreateCommand)
diff --git a/spec/cli_spec.rb b/spec/cli_spec.rb
new file mode 100644
index 0000000..ef2eb8a
--- /dev/null
+++ b/spec/cli_spec.rb
@@ -0,0 +1,104 @@
+require 'spec_helper'
+require 'tempfile'
+require 'open3'
+
+RSpec.describe 'readwise CLI' do
+  let(:cli_path) { File.expand_path('../../exe/readwise', __FILE__) }
+  let(:test_html) { '<p>Test content</p>' }
+  let(:temp_file) do
+    file = Tempfile.new(['test', '.html'])
+    file.write(test_html)
+    file.close
+    file
+  end
+
+  after do
+    temp_file.unlink if temp_file
+  end
+
+  def run_cli(*args)
+    env = { 'READWISE_API_KEY' => 'test_token' }
+    Open3.capture3(env, 'ruby', cli_path, *args)
+  end
+
+  def run_cli_without_token(*args)
+    env = {}
+    Open3.capture3(env, 'ruby', cli_path, *args)
+  end
+
+  describe 'help and error handling' do
+    it 'shows help when --help is passed' do
+      stdout, _stderr, status = run_cli('--help')
+
+      expect(status.success?).to be true
+      expect(stdout).to include('Usage: readwise')
+      expect(stdout).to include('Available commands:')
+    end
+
+    it 'shows help when no arguments are provided' do
+      stdout, _stderr, status = run_cli()
+
+      expect(status.success?).to be false
+      expect(stdout).to include('Usage: readwise <resource> <action>')
+    end
+
+    it 'shows error for unknown command' do
+      stdout, _stderr, status = run_cli('unknown', 'command')
+
+      expect(status.success?).to be false
+      expect(stdout).to include("Error: Unknown command 'unknown command'")
+    end
+
+    it 'shows error when resource or action is missing' do
+      stdout, _stderr, status = run_cli('document')
+
+      expect(status.success?).to be false
+      expect(stdout).to include('Error: Resource and action are required')
+    end
+  end
+
+  describe 'document create command' do
+    it 'shows help for document create command' do
+      stdout, _stderr, status = run_cli('document', 'create', '--help')
+
+      expect(status.success?).to be true
+      expect(stdout).to include('Usage: readwise document create')
+      expect(stdout).to include('Sends HTML content to Readwise Reader API')
+    end
+
+    it 'shows error when neither a file path or URL is provided' do
+      stdout, _stderr, status = run_cli('document', 'create')
+
+      expect(status.success?).to be false
+      expect(stdout).to include('Error: File path or URL is required')
+    end
+
+    it 'shows error when file does not exist' do
+      stdout, _stderr, status = run_cli('document', 'create', '--html-file', 'nonexistent.html')
+
+      expect(status.success?).to be false
+      expect(stdout).to include("Error: File 'nonexistent.html' not found")
+    end
+
+    it 'shows error when READWISE_API_KEY is not set' do
+      stdout, _stderr, status = run_cli_without_token('document', 'create', '--html-file', temp_file.path)
+
+      expect(status.success?).to be false
+      expect(stdout).to include('Error: READWISE_API_KEY environment variable is not set')
+    end
+
+    it 'shows error for invalid location' do
+      stdout, _stderr, status = run_cli('document', 'create', '--location=invalid', '--html-file', temp_file.path)
+
+      expect(status.success?).to be false
+      expect(stdout).to include('Error: Invalid location. Must be one of: new, later, archive, feed')
+    end
+
+    it 'shows error for invalid category' do
+      stdout, _stderr, status = run_cli('document', 'create', '--category=invalid', '--html-file', temp_file.path)
+
+      expect(status.success?).to be false
+      expect(stdout).to include('Error: Invalid category. Must be one of: article, email, rss, highlight, note, pdf, epub, tweet, video')
+    end
+  end
+end