Anthropic

Anthropic is the AI lab behind the Claude model family and the Claude API, with a research focus on interpretability and safety, the creator of the MCP standard, and the vendor whose models are the default choice in coding and agentic workloads.

Why founders use it: Claude's reputation in code, long documents and instruction-following makes it the default backend for developer tools, agents and anything that must act reliably on structured input. The API's tool use and prompt caching, which cuts the cost of long stable contexts dramatically, are the practical differentiators for product builders.

A realistic use: an agent product standardizing on Claude for planning and code execution, with prompt caching on the system prompt and tool definitions, streaming for responsiveness, and batch endpoints for offline workloads.

Trade-offs: pricing sits at the premium end per token, rate limits scale with spend history, and multimodal breadth trails some competitors. Compare with the OpenAI and Gemini blocks here per workload; the honest answer is benchmarking your prompts, not the marketing leaderboards.