Anthropic releases Claude Sonnet 5
Anthropic releases Claude Sonnet 5 with stronger agent planning, tool use, coding, knowledge work and long-running autonomous execution.
What happened
Event details
Claude Sonnet 5 is a generational upgrade over Sonnet 4.6 for workloads that balance speed, cost and agent capability. It supports planning and tools such as browser and terminal use, and can carry out multi-step coding and knowledge work. It provides a 1-million-token context window and up to 128K output. Anthropic deployed it to all Claude plans, Claude Code, the Claude API and major cloud platforms on June 30, 2026; the API identifier is claude-sonnet-5.
Assessment
Why it matters
A published model record with a documented capability or availability change.
Availability
Access notes
Publicly available in all Claude plans, Claude Code, the Claude API and major cloud platforms from June 30, 2026.