Claude

Claude is built by Anthropic, an AI safety company co-founded by former OpenAI researchers. The current flagship is Claude Sonnet 4 — highly capable across writing, coding, and reasoning tasks.

Anthropic's focus on safety and alignment means Claude tends to be more thoughtful about nuance and less likely to produce misleading content than some competitors.

Claude has a 200,000 token context window — one of the largest available. You can hand it a full book, a 100-page document, or an entire codebase and ask it to work with the whole thing at once.

It consistently performs well on tasks that require:

Following complex, multi-part instructions

Maintaining consistent tone and style across long documents

Nuanced analysis and reasoning

Writing that sounds like a real human wrote it

Claude Code is a terminal-based coding agent that reads your codebase, writes code, runs tests, and commits changes — autonomously. It's what was used to build 313SESSIONS.

For developers and technical founders, it represents a significant productivity multiplier — not just writing code snippets, but understanding the full context of a project and making changes that actually work.

claude.ai is the main interface. The free tier is generous. Claude Pro ($20/mo) gives higher usage limits and access to the most capable models.

For developers: the Anthropic API gives programmatic access. Claude models are available through Amazon Bedrock and Google Cloud as well.

Use Claude when:

You're working with long documents

You need it to follow detailed, complex instructions precisely

You want writing that sounds more natural

You're doing nuanced analysis

Use ChatGPT when:

You need a specific plugin or integration

You want image generation built in

You're doing data analysis with code interpreter

You want the widest ecosystem support