Developed foundational global model definitions and cost evaluation scaffolding within the braintrustdata/braintrust-proxy repository, enabling cost analytics for Claude Sonnet 4.5, Sonnet 4.6, and Haiku 4.5 models. Leveraged TypeScript and JSON to implement integration-ready configurations that support multi-model cost calculation, directly addressing a business requirement for platform cost visibility. Focused on backend development and data modeling, the work established a unified model layer to facilitate accurate pricing analytics and cross-model comparisons in production. Documented blockers and outlined resolution paths, ensuring the groundwork for future cost visibility features was robust and aligned with ongoing business augmentation needs.