When no explicit session signals (session_id, conversation_id, prompt_cache_key)
are provided, derive a stable session seed from the request body content
(model + tools + system prompt + first user message) to enable sticky routing
and prompt caching for non-Codex clients using the Chat Completions API.
This mirrors the content-based fallback already present in GatewayService.
GenerateSessionHash, adapted for the OpenAI gateway's request formats (both
Chat Completions messages and Responses API input).
JSON fragments are canonicalized via normalizeCompatSeedJSON to ensure
semantically identical requests produce the same seed regardless of
whitespace or key ordering.
Closes#1421
Anthropic compat requests normalize reasoning suffixes before forwarding, but the account mapping step was still using the raw request model. Resolve billing and upstream models from the normalized compat model so explicit account mappings win over fallback defaults.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
When multiple goroutines/workers concurrently refresh the same OAuth token,
the first succeeds but invalidates the old refresh_token (rotation). Subsequent
attempts using the stale token get invalid_grant, which was incorrectly treated
as non-retryable, permanently marking the account as ERROR.
Three complementary fixes:
1. Race-aware recovery: after invalid_grant, re-read DB to check if another
worker already refreshed (refresh_token changed) — return success instead
of error
2. In-process mutex (sync.Map of per-account locks): prevents concurrent
refreshes within the same process, complementing the Redis distributed lock
3. Increase default lock TTL from 30s to 60s to reduce TTL-expiry races
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Replace charset→base64url double-encoding with standard random
bytes→base64url approach to match official client behavior and avoid
risk control detection.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Align OAuth scopes with upstream Claude Code client which now includes
the user:file_upload scope for file upload support.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Cover isAntigravityInternalServerError body matching,
applyInternal500Penalty tier escalation, handleInternal500RetryExhausted
nil-safety and error handling, and resetInternal500Counter paths.
Move constants, detection, and penalty functions from
antigravity_gateway_service.go to antigravity_internal500_penalty.go.
Fix gofmt alignment and replace hardcoded duration strings with
constant references.
