## Feature Already Exists This feature has been **fully implemented** as part of **PPLX-23**. **Evidence:** - `create_api_usage_log()` already accepts all cost breakdown fields (crud.py:412-459) - Database model has all columns: `input_tokens_cost`, `output_tokens_cost`, `request_cost`, `api_total_cost` (models.py:236-241) - `estimated_cost_usd` is maintained for backward compatibility - Migration `a534488c3a48` has been applied - Router already passes all cost data to CRUD function (queries.py:197-209) Marking as **cancelled** (duplicate of PPLX-23). See attached triage report for full details.