Claude

Claude is Anthropic's AI writing assistant, particularly well-suited for tasks that require coherence across large amounts of context. Its 200K token context window — among the largest available — means you can load an entire research brief, a full manuscript draft, a set of source documents, and a style guide into a single session and get back writing that accurately reflects all of it. Long documents stay coherent from start to finish in a way that most models struggle with as context grows.

The quality of Claude's output tends to be strongest in domains that reward careful reasoning: legal writing, technical documentation, research synthesis, long-form journalism, and complex analysis. It follows nuanced instructions reliably and is resistant to veering off in an unwanted direction mid-document.

Claude is available directly at Claude.ai and via the Anthropic API. Anthropic also ships Claude Code, a terminal-based CLI that brings Claude's reasoning to software engineering — planning and executing changes across an entire codebase, running tests, and integrating into CI/CD pipelines.

The Projects feature lets you maintain persistent context across multiple working sessions with the same documents. A long research project, a book manuscript, or an ongoing technical analysis can stay open in a persistent Project where Claude retains the full document history, your instructions, and any notes — so each session picks up where the last left off rather than requiring you to re-establish context from scratch.

For analytical writing specifically — research synthesis, technical documentation, legal analysis — Claude's ability to reason carefully through complex material and maintain logical consistency across a long document is particularly strong. It follows the structure and argument you establish in the opening sections and holds to it through to the conclusion, rather than drifting in tone or direction as the document length grows.

Claude.ai is available with a free tier that covers most individual use cases. The Pro tier adds priority access during high usage periods and extended context for working with very large documents. For development teams, the Anthropic API provides programmatic access to Claude with options for tool use and integration into existing workflows. Claude Code, the terminal-native CLI, extends this to agentic coding work — planning changes, running tests, and integrating into CI pipelines.