Semantic conventions

Attribute/Namespace	Meaning	When Required?	Is Namespace?	Type
`ai.observability.span_type`	Span type. This states what kind of span this is. E.g. "retrieval", "generation", "unknown", "record root". Given a span type, we can assume there might be relevant fields in `ai.observability.<span type>`. For example, for a span of type "record_root", there'll be more span attributes in the namespace `ai.observability.record_root`	Never		str
`ai.observability.record_id`	Record ID. This ties all spans of a single invocation to the app together. We don't use the trace id for this purpose because a trace may have multiple records (i.e. app invocations).	Always		str
`ai.observability.app_id`	App ID.	Always		str
`ai.observability.app_name`	App name.	Always		str
`ai.observability.app_version`	App version.	Always		str
`ai.observability.run.name`	Run name. Runs represent a set of invocations to the app.	Always for Snowflake for non-evaluation spans		str
`ai.observability.input_id`	ID of the input to the app for this record.	Always for Snowflake for non-evaluation spans		str
`ai.observability.span_groups`	List of groups that the span belongs to. This is primarily used for metric computation.	Never		str \| List[str]
`ai.observability.record_root`	Namespace for attributes specific to the record root.		Y
`ai.observability.record_root.input`	Main input to the app for this record.	Never		Any (but usually str)
`ai.observability.record_root.output`	Main output to the app for this record.	Never		Any (but usually str)
`ai.observability.record_root.error`	Error thrown by app for this record. Exclusive with main output.	Never		Any (but usually str)
`ai.observability.record_root.ground_truth_output`	Ground truth of the record.	Never		Any (but usually str)
`ai.observability.eval_root`	Namespace for attributes specific to the root span of a feedback evaluation.	Never	Y
`ai.observability.eval_root.metric_name`	Name of the feedback definition being evaluated.	Always for eval_root spans		str
`ai.observability.eval_root.span_group`	Span group of the inputs to this metric.	Never		str
`ai.observability.eval_root.args_metadata.span_id`	Mapping of argument name of the feedback function to the ID of the span that provided it. E.g. if the feedback function has an input `x` that came from a span with id "123", then `ai.observability.eval_root.args_metadata.span_id.x` will have value "123".	Always for evaluation root spans	Y	str -> str
`ai.observability.eval_root.args_metadata.span_attribute`	Mapping of argument name of the feedback function to the attribute of the span that provided it. E.g. if the feedback function has an input `x` that came from a span attribute "abc", then `ai.observability.eval_root.args_metadata.span_attribute.x` will have value "abc".	Never	Y	str -> str
`ai.observability.eval_root.error`	Error raised during evaluation.	Never		Any (but usually str)
`ai.observability.eval_root.score`	Score of the evaluation.	Always for evaluation root spans		float
`ai.observability.eval_root.higher_is_better`	Whether higher is better for this feedback function.	Never		bool
`ai.observability.eval_root.metadata`	Any other metadata of the evaluation.	Never	Y	str -> Any
`ai.observability.eval`	Namespace for attributes specific to feedback function evaluation spans.		Y
`ai.observability.eval.target_record_id`	Record id of the record being evaluated.	Never		str
`ai.observability.eval.eval_root_id`	Span id for the "eval_root" span this span is under.	Always for eval or eval_root spans		str
`ai.observability.eval.criteria`	Criteria for this sub-step.	Never		str
`ai.observability.eval.explanation`	Explanation for the score for this sub-step.	Never		str
`ai.observability.eval.score`	Score for this sub-step.	Never		float
`ai.observability.cost`	Namespace for cost information.	Never	Y
`ai.observability.cost.cost`	Cost.	Never		float
`ai.observability.cost.cost_currency`	Currency of the cost.	Never		str
`ai.observability.cost.model`	Model used that caused any costs.	Never		str
`ai.observability.cost.num_tokens`	Total tokens processed.	Never		int
`ai.observability.cost.num_prompt_tokens`	Number of prompt tokens supplied.	Never		int
`ai.observability.cost.num_completion_tokens`	Number of completion tokens generated.	Never		int
`ai.observability.call`	Namespace for instrumented method call attributes.		Y
`ai.observability.call.function`	Name of function being tracked.	Never		str
`ai.observability.call.kwargs`	Namespace from function's argument name to value. E.g. if the function has a parameter `x` whose value was "y", then we'd have `ai.observability.call.kwargs.x` have value "y".	Never	Y	str -> Any
`ai.observability.call.return`	Return value of the function if it executed without error.	Never		Any
`ai.observability.call.error`	Error raised by the function if it executed with an error.	Never		Any (but usually str)
`ai.observability.retrieval`	Namespace for attributes specific to a retrieval span.		Y
`ai.observability.retrieval.query_text`	Input text whose related contexts are being retrieved.	Never		str
`ai.observability.retrieval.num_contexts`	The number of contexts requested, not necessarily retrieved.	Never		int
`ai.observability.retrieval.retrieved_contexts`	The retrieved contexts.	Never		List[str]
`ai.observability.mcp`	Namespace for attributes specific to Model Context Protocol (MCP) tool calls.		Y
`ai.observability.mcp.tool_name`	Name of the MCP tool being called.	Never		str
`ai.observability.mcp.tool_description`	Description of the MCP tool.	Never		str
`ai.observability.mcp.server_name`	Name of the MCP server providing the tool.	Never		str
`ai.observability.mcp.input_schema`	Schema of the input parameters for the MCP tool.	Never		str
`ai.observability.mcp.input_arguments`	Arguments passed to the MCP tool.	Never		str
`ai.observability.mcp.output_content`	Content returned by the MCP tool.	Never		str
`ai.observability.mcp.output_is_error`	Whether the MCP tool call resulted in an error.	Never		bool
`ai.observability.mcp.execution_time_ms`	Time taken to execute the MCP tool call in milliseconds.	Never		float
`ai.observability.generation`	Namespace for attributes specific to a generation span.		Y
`ai.observability.graph_task`	Namespace for attributes specific to a graph task function execution span.		Y
`ai.observability.graph_task.task_name`	Name of the task function.	Never		str
`ai.observability.graph_task.input_state`	Input state to the task.	Never		Any
`ai.observability.graph_task.output_state`	Output state from the task.	Never		Any
`ai.observability.graph_task.error`	Error raised during task execution.	Never		Any (but usually str)
`ai.observability.graph_node`	Namespace for attributes specific to a graph node execution span.		Y
`ai.observability.graph_node.node_name`	Name of the node.	Never		str
`ai.observability.graph_node.input_state`	Input state to the graph.	Never		Any
`ai.observability.graph_node.output_state`	Output state from the graph.	Never		Any
`ai.observability.graph_node.latest_message`	Latest message flowing between nodes.	Never		Any
`ai.observability.graph_node.nodes_executed`	List of nodes executed in the graph.	Never		List[str]
`ai.observability.graph_node.error`	Error raised during graph execution.	Never		Any (but usually str)
`ai.observability.workflow`	Namespace for attributes specific to a workflow execution span.		Y
`ai.observability.workflow.input_event`	Input event to the workflow.	Never		Any
`ai.observability.workflow.output_event`	Output event from the workflow.	Never		Any
`ai.observability.workflow.error`	Error raised during workflow execution.	Never		Any (but usually str)
`ai.observability.workflow.agent_name`	Name of the agent executing in the workflow.	Never		str
`ai.observability.agent`	Namespace for attributes specific to an agent execution span.		Y
`ai.observability.tool`	Namespace for attributes specific to a tool/function call execution span.		Y
`ai.observability.reranking`	Namespace for attributes specific to a reranking operation span.		Y
`ai.observability.reranking.query_text`	Query text used for reranking.	Never		str
`ai.observability.reranking.model_name`	Name of the reranking model.	Never		str
`ai.observability.reranking.top_n`	Number of top results to return after reranking.	Never		int
`ai.observability.reranking.input_context_texts`	Input contexts before reranking.	Never		List[str]
`ai.observability.reranking.input_context_scores`	Input scores before reranking.	Never		List[float]
`ai.observability.reranking.input_ranks`	Input ranking order before reranking.	Never		List[int]
`ai.observability.reranking.output_ranks`	Output ranking order after reranking.	Never		List[int]
`ai.observability.reranking.output_context_texts`	Output contexts after reranking.	Never		List[str]
`ai.observability.reranking.output_context_scores`	Output scores after reranking.	Never		List[float]