Frequently asked questions

Claude Code is Anthropic's official CLI for using Claude directly in the terminal. It has full filesystem access, can run commands, and acts as a development agent. It's not just autocomplete: it can implement complete features, refactor code, run tests, and debug errors autonomously.

Claude excels at long reasoning, precise instruction following, and large context (up to 200K tokens). Its API is more predictable and reliable for production use. Claude Code as a development tool has no direct equivalent in the OpenAI ecosystem.

MCP is a standard protocol that lets Claude connect to external tools and data sources. With an MCP server you can give Claude access to your database, internal APIs, Slack, Jira or any service. It's what turns Claude Code from a code editing tool into an agent connected to your infrastructure.

Claude API is billed per token. Claude Sonnet 4 costs approximately $3 per million input tokens and $15 per million output tokens. With prompt caching enabled, cached tokens cost 90% less. For most development projects the monthly cost is between $20 and $200 depending on usage volume.

Prompt caching lets you mark parts of the prompt so Anthropic stores them temporarily. Subsequent requests using that cached portion cost 90% less. In projects with long system prompts or fixed context, savings can be 70-80% of the total bill.

They're different tools. Copilot lives in the editor and autocompletes code in real time. Claude Code operates as an agent in the terminal and can execute complete tasks: implement an endpoint, write tests, refactor and commit. For complex autonomous tasks, Claude Code goes far beyond what Copilot can do.

AI agents can automate tasks that previously required constant manual intervention: reviewing PRs, running test suites and analyzing failures, generating documentation, monitoring logs, or implementing features from a description. The value is in eliminating repetitive low-level work.

Create an account at console.anthropic.com and get an API key. Install the official SDK (Python, TypeScript and others). The most basic call sends a message and receives a response. From there add system prompts, history, tool use and prompt caching as needed.