Call schema reference

This page provides a reference for the Call object schema in W&B Weave. For information on querying calls, see Query and export calls.

Call properties

The table below outlines the key properties of a Call in Weave. For the complete implementation, see:

Property	Type	Description
`id`	string (uuid)	Unique identifier for the call
`project_id`	string (optional)	Associated project identifier
`op_name`	string	Name of the operation (can be a reference)
`display_name`	string (optional)	User-friendly name for the call
`trace_id`	string (uuid)	Identifier for the trace this call belongs to
`parent_id`	string (uuid)	Identifier of the parent call
`started_at`	datetime	Timestamp when the call started
`attributes`	Dict[str, Any]	User-defined metadata about the call (read-only during execution)
`inputs`	Dict[str, Any]	Input parameters for the call
`ended_at`	datetime (optional)	Timestamp when the call ended
`exception`	string (optional)	Error message if the call failed
`output`	Any (optional)	Result of the call
`summary`	Optional[SummaryMap]	Post-execution summary information. You can modify this during execution to record custom metrics.
`wb_user_id`	Optional[str]	Associated W&B user ID
`wb_run_id`	Optional[str]	Associated W&B run ID
`deleted_at`	datetime (optional)	Timestamp of call deletion, if applicable

CallSchema properties play an important role in tracking and managing function calls:

The id, trace_id, and parent_id properties help organize and relate calls within the system.
Timing information (started_at, ended_at) support performance analysis.
The attributes and inputs properties provide context for the call. Attributes are frozen once the call starts, so set them before invocation with weave.attributes. output and summary capture the results. -You can store metrics or other post-call values in the summary property. Modify call.summary during execution. Any values you add is merged with Weave’s computed summary data when the Call finishes.
- Weave’s computed summary data:
  - costs: The total cost of the call based on LLM model usage data and token pricing data. For more information on cost calculation, see Track costs.
  - latency_ms: The duration, in milliseconds, elapsed between started_at and ended_at. null if status is RUNNING.
  - status: The execution status: SUCCESS, ERROR, RUNNING, DESCENDANT_ERROR (meaning the call itself succeeded but a descendant call errored).
Integration with W&B is facilitated through wb_user_id and wb_run_id.

This comprehensive set of properties enables detailed tracking and analysis of function calls throughout your project.