- Added designer model role for UI/UX design tasks with Gemini 3.1 Pro as default model.
- Implemented model role fallback list support enabling automatic fallback to next available model when primary is unavailable.
- Refactored model role resolution to support multiple fallback patterns per role with thinking level mapping.
- Updated designer agent to use pi/designer role alias instead of explicit model list, removing spawns configuration.
- Added test coverage for model resolver fallback patterns and designer role override preferences.
- Added test coverage for geminiImageTool X-Title header routing through OpenRouter.
- Added serviceTier option to OpenAI providers for controlling processing priority and cost across agent, completions, responses, and codex APIs.
- Added providerPayload field to messages for transport-native history reconstruction in OpenAI Responses and Codex APIs.
- Added /fast slash command and serviceTier setting to coding-agent for toggling OpenAI priority mode with fast mode indicator.
- Added remote compaction support with encrypted reasoning preservation for OpenAI models in coding-agent.
- Removed usage caching layer across all providers and refactored UsageFetchContext to eliminate cache and now dependencies.
- Fixed OpenAI Codex streaming service_tier inclusion, provider retry logic with exponential backoff, and email-based credential deduplication.
- Extracted model priority configuration from TypeScript constants to external priority.json file.
- Updated agent prompts (reviewer, explore, plan) to reference new model tier aliases (pi/slow, pi/smol, pi/plan).
- Removed hardcoded SMOL_MODEL_PRIORITY and SLOW_MODEL_PRIORITY constants from model-resolver.ts.
- Improved prompt formatting with consistent newlines and whitespace in agent configuration files.
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