Sonnet 5 propagated across harnesses in one week: Claude Code makes it the default (1M context); Pi adds support
What this changes for operators
- Claude Code v2.1.197 (2026-06-30) makes Claude Sonnet 5 the default model, with native 1M-token context. Pi v0.80.3 (2026-06-30) added Sonnet 5 support (Anthropic-compatible + Bedrock) the same week. A new frontier model became a default and a cross-harness option within days.
- Know your default changed: if you pin models for cost/behavior reasons, confirm whether you are now on Sonnet 5 with a 1M window (and the cost/latency that implies), or set the model explicitly.
Primary sources
Signal metadata
Source findings
- 2026-07-01-claude-code-v2-1-197-claude-sonnet-5-becomes-the-default-model-in-cl 2026-07-01-claude-code-v2-1-197-claude-sonnet-5-becomes-the-default-model-in-cl
- 2026-07-01-pi-coding-agent-v0-80-3-adds-claude-sonnet-5-support-anthropic-compatibl 2026-07-01-pi-coding-agent-v0-80-3-adds-claude-sonnet-5-support-anthropic-compatibl
Featured in
- Patched for Whom / 2026-07-01
Run: 2026-07-01-weekly-digest-2026-06-24_2026-07-01-frontier-v0
Schema: bitter.frontier_signals.v0 / ID: 2026-07-01-sonnet-5-propagation-default-and-adopted
Research evidence and publication history are open in the repository.