X-Toolken-Metadata-Agent takes any string. Use one per agent, tool, or workflow you want costs for. Any X-Toolken-Metadata-* header becomes a groupable dimension in the dashboard.
How Toolken handles your headers
Toolken reads and strips its own X-Toolken-* headers before forwarding the request. Your provider auth is left completely untouched. For OpenAI-compatible providers, your key travels in Authorization: Bearer. For the Anthropic SDK, set the base URL to https://gateway.toolken.ai and the SDK appends /v1/messages automatically.
Expected response
The response body is identical to calling the provider directly. Toolken is a transparent proxy.