llm-connect/contracts/functional/rates.md

Model Rate Registry

llm_connect.rates owns static model list prices used for planning and post-hoc estimates.

Contract

• ModelRate records model_id, prompt and completion rates in USD per 1,000 tokens, currency, source_url, and captured_at.
• ModelRateRegistry.default() returns the bundled OpenRouter snapshot captured on 2026-05-17.
• ModelRateRegistry.from_yaml(path) accepts the package/consumer override shape:

schema_version: 1
currency: USD
source_url: https://openrouter.ai/models
captured_at: "2026-05-17"
rates:
  openai/gpt-4o-mini:
    prompt_per_1k: 0.00015
    completion_per_1k: 0.00060

• merged_with(override) returns a new registry where matching override entries replace default entries by model_id.

Rates are a static snapshot. Consumers decide whether captured_at is fresh enough for their workflow.