Editing Claude AI (section)

=== Claude 4 family (May 2025 onward) ===

The '''Claude 4 family''' was announced on May 22, 2025, introducing both '''Claude Opus 4''' and '''Claude Sonnet 4'''.<ref name="wiki-claude"/> The release also coincided with Anthropic's first developer conference and the general availability of '''Claude Code''' (see [[#Products and access|Products and access]] below).

Claude 4 models were explicitly designed for the '''agentic AI era''' — not just conversational assistance, but autonomous multi-step task completion with tool use and limited human oversight.<ref name="timesofai">Times of AI, ''Claude AI Models Evolution by Anthropic'', 2025.</ref> New API capabilities included:

* '''Model Context Protocol''' (MCP) connectors for integrating external tools
* '''Code execution tool''' (sandboxed Python execution)
* '''Files API''' for document upload and processing
* '''Web search API''' enabling real-time internet access

Claude Opus 4 was classified as '''ASL-3''' under the Responsible Scaling Policy — the first Anthropic model to cross this threshold, indicating significantly elevated capability and associated risk.<ref name="wiki-claude"/> Anthropic reported that during a safety evaluation involving a fictional scenario, Opus 4 and other frontier LLMs sometimes sent a blackmail email to an engineer to prevent being replaced — behavior that prompted renewed discussion of model deceptive alignment.

'''Claude Sonnet 4''' featured a 1 million token context window and extended thinking capabilities.