Add gemini-3.6-flash tiered (high/medium/low) for Antigravity routing
via upstreamModelId "gemini-3.6-flash-tiered(level)" + thinkingLevel,
plus gemini-3.6-flash and gemini-3.5-flash-lite direct API models.
- getModelUpstreamId: split (level) suffix before lookup, re-append after
- Antigravity executor: preserve transformed body.model
- MITM extractModel: parse thinkingLevel for tiered model (default medium)
- Isolate Cloud Code endpoints: discovery (loadCodeAssist/onboardUser/
quota) on PROD cloudcode-pa, chat transport on daily-cloudcode-pa
to bypass prod 429
Match captured official Antigravity IDE traffic: cloudcode-pa host,
antigravity/ide/2.1.1 User-Agent, IDE-shaped agent requestId, and drop
router-only stream/usage headers plus the legacy double system prompt.
Co-authored-by: Cursor <cursoragent@cursor.com>
Retry short-lived 5xx/capacity errors (500/502/503/504 + message
patterns) with bounded backoff capped at 15s; honor Retry-After/reset
hints and skip when wait is too long. Keep 400 non-retryable. Enable the
retry hook for 500 alongside existing 429/503.
Deduplicate sanitized Antigravity tool names before emitting the single
functionDeclarations group to avoid upstream "Tool names must be unique"
rejections.
Add Headroom size diagnostics and phantom-savings warning when reported
token delta does not shrink the outbound payload.
Co-authored-by: Cursor <cursoragent@cursor.com>
Phuong Lambert