> ## Documentation Index
> Fetch the complete documentation index at: https://openrouter.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# CostDetails

Breakdown of upstream inference costs

## Fields

| Field | Type | Required | Description |
| - | - | - | - |
| `server_tool_cost` | *OptionalNullable\[float]* | :heavy\_minus\_sign: | Metered server-tool execution cost (for example, shell sandbox time) billed for this request, in USD. Matches the billed checkpoint and settlement amounts exactly. 0 when a metered server tool ran but settled at zero dollars; absent when no metered server tool ran. |
| `upstream_inference_completions_cost` | *float* | :heavy\_check\_mark: | N/A |
| `upstream_inference_cost` | *OptionalNullable\[float]* | :heavy\_minus\_sign: | N/A |
| `upstream_inference_prompt_cost` | *float* | :heavy\_check\_mark: | N/A |