[jayypatel18]

What

This moves the API requests that send claude-sonnet-4-5 to claude-sonnet-5-5.

• src/lib/analyzer.ts: DEFAULT_ANALYZER_MODEL goes from claude-sonnet-4-5-20250929 to claude-sonnet-5-5, because the analyzer sends this default as its request model and the old id is retiring.
• src/lib/env-check.ts: the model in the client.messages.create call inside checkApiKey changes from claude-sonnet-4-5-20250929 to claude-sonnet-5-5, so the key check runs against a model that stays available.
• src/commands/analyze.ts: the --model help text now says the default is claude-sonnet-5-5, so it matches the new DEFAULT_ANALYZER_MODEL.
• src/commands/run.ts: the --analyzer-model help text and the oasis config set default-model hint now name claude-sonnet-5-5 instead of claude-sonnet-4-5-20250929, so users are pointed at the model that is still served.

What changes for you

• Thinking runs by default. A request with no thinking field ran without thinking on Claude Sonnet 4.5 and runs with adaptive thinking on Claude Sonnet 5.5. Thinking tokens are billed as output tokens, and max_tokens covers thinking plus text. max_tokens is not changed here.
• The guide says to revisit max_tokens. What these requests send today, unchanged: src/lib/env-check.ts (max_tokens: 1).
• The same text produces about 30% more tokens than on Claude Sonnet 4.5, depending on the content.
• Not changed, because they describe the old model and send no request: src/commands/providers.ts (line 20), src/lib/providers.ts (line 19), tests/unit/report.test.ts (lines 14, 73, 116).

Why

Claude Sonnet 4.5 (claude-sonnet-4-5-20250929) is deprecated and retires on November 30, 2026. Requests to a retired model fail. The recommended replacement is claude-sonnet-5-5.

• Model deprecations: https://platform.claude.com/docs/en/about-claude/model-deprecations
• Migration guide: https://platform.claude.com/docs/en/models/sonnet-5-5/migration-guide

How

Only the places that send a request, or tell a user which model is the default, were changed. Entries that describe the old model (the provider list and the test fixtures) are left as they are. src/commands/run.ts line 21 still shows claude-sonnet-4-5-20250929 in a help example; say if you want that changed too.

Checklist

• Tests added/updated
• npm run typecheck passes
• npm test passes
• npm run build succeeds

What I checked

In a clean Node 20 container, on main (22b57a4) and then on this branch, with install scripts off:

Step	main	this branch
npm install	ok	ok
npm test	466 passed	466 passed
tsc --noEmit	no errors	no errors
npm run typecheck	ok	ok
npm run build	ok	ok

Not checked: No request was sent to the API, so the model's answers, cost and latency were not compared. The app was not run.