Authentication

Remote MCP servers expose powerful capabilities over the network. Without auth, anyone with the URL could query your database or send Slack messages.

MCP authentication is the bouncer at a club — your credentials get you in, and the bouncer knows which VIP sections (tools) you can access.

Scenario

A GitHub MCP server requires OAuth with repo:read scope. Users who haven't authorized get a prompt; authorized users can call search_code and read_file tools.

Solution

In Model Context Protocol, apply Authentication to this scenario: A GitHub MCP server requires OAuth with repo:read scope. Identify the inputs, run the technique, validate the output, and note one thing you would monitor in production.

Do this before moving to the next module — reading alone is not enough.

Open the Code Walkthrough below and run it locally. Change one parameter related to Authentication (e.g. model, temperature, top_k, or tool name), observe the difference in output, and write 2–3 sentences explaining what changed.

Highlighted lines show where Authentication happens in the code.

1# Authentication — minimal example2from openai import OpenAI3
4client = OpenAI()  # create API client5
6# Ask the model to explain this topic7response = client.chat.completions.create(  # core API call for Authentication8    model="gpt-4o-mini",9    messages=[10        {"role": "system", "content": "You explain authentication clearly."},11        {"role": "user", "content": f"What is authentication?"},12    ],13    temperature=0,14)15print(response.choices[0].message.content)  # show output for debugging

• Treating Authentication as a black box without evaluation
• Ignoring cost and latency in production
• Skipping error handling for authentication

Quick recap — the most important points from this module.