Improve all readmes (#188)

* Improve all readmes

* Address some of the comments

mcp-client-ruby/README.md

@@ -1,6 +1,36 @@
 # An LLM-Powered Chatbot MCP Client written in Ruby
 
-See the [Build an MCP client](https://modelcontextprotocol.io/docs/develop/build-client) tutorial for more information.
+An interactive chatbot MCP client: it launches an MCP server over stdio, lists its tools, and hands them to Claude, which can call them while answering your questions.
+
+This example accompanies the [Build an MCP client](https://modelcontextprotocol.io/docs/develop/build-client) tutorial.
+
+## Prerequisites
+
+- Ruby 3.4+ (3.3 also satisfies the gems)
+- Bundler
+- An [Anthropic API key](https://console.anthropic.com/) (optional — see below)
+
+## Setup
+
+Install the gems, then put your API key in a `.env` file (or export `ANTHROPIC_API_KEY` in your shell):
+
+```bash
+bundle install
+cp .env.example .env
+# then edit .env and add your key
+```
+
+## Run the client
+
+Pass the path to a server script. `.rb` servers are launched with `ruby`, `.py` with `python3`, and `.js` with `node`:
+
+```bash
+bundle exec ruby client.rb ../weather-server-ruby/weather.rb
+```
+
+Type a question (for example, "What's the weather in Sacramento?") and Claude answers using the server's tools. Type `quit` to exit.
+
+Without an `ANTHROPIC_API_KEY`, the client still connects, prints the server's tools, and exits — useful for verifying the MCP wiring without credentials.
 
 ## Structured content