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>
Propagate UpstreamModel through ForwardResult and OpenAIForwardResult in Anthropic direct, API-key passthrough, Bedrock, and OpenAI gateway flows. Extract optionalNonEqualStringPtr and optionalTrimmedStringPtr into usage_log_helpers.go. Store upstream_model only when it differs from the requested model.
Also introduces anthropicPassthroughForwardInput struct to reduce parameter count.
Two SSE scanners in openai_gateway_messages.go were hardcoded to 1MB
while all other scanners use defaultMaxLineSize (500MB) with config
override. This caused Responses API streams to fail on large payloads.
- Add recoverAnthropicMessagesPanic for Messages handler to return
Anthropic-formatted errors instead of OpenAI Responses format on panic
- Add nil check for rateLimitService.HandleUpstreamError in
ForwardAsAnthropic to match defensive pattern used elsewhere
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add Anthropic Messages API support for OpenAI platform groups, enabling
clients using Claude-style /v1/messages format to access OpenAI accounts
through automatic protocol conversion.
- Add apicompat package with type definitions and bidirectional converters
(Anthropic ↔ Chat, Chat ↔ Responses, Anthropic ↔ Responses)
- Implement /v1/messages endpoint for OpenAI gateway with streaming support
- Add model mapping UI for OpenAI OAuth accounts (whitelist + mapping modes)
- Support prompt caching fields and codex OAuth transforms
- Fix tool call ID conversion for Responses API (fc_ prefix)
- Ensure function_call_output has non-empty output field
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
