Event schema

Every AgentEvent contains the same envelope:

Field	Type	Meaning
`schema_version`	`str`	Serialized contract version, currently `1.0`
`event_id`	`str`	UUID4 identifier for this event
`run_id`	`str`	UUID4 identifier shared by a run
`event_type`	`str`	Validated standard or explicitly allowed custom type
`timestamp`	`str`	ISO 8601 UTC timestamp ending in `Z`
`agent_name`	`str \\| null`	Stable logical agent name
`workflow_name`	`str \\| null`	Stable workflow name
`parent_event_id`	`str \\| null`	Optional causal parent event
`provider`	`str \\| null`	Model provider where applicable
`model`	`str \\| null`	Model identifier where applicable
`tool_name`	`str \\| null`	Tool identifier where applicable
`status`	`str \\| null`	Outcome or lifecycle status
`payload`	`object`	Event-specific data
`risk`	`object`	Classification and risk context
`metadata`	`object`	Operational context

Standard types

run_start, run_end, user_message, system_instruction, model_call, model_response, tool_call, tool_result, retrieval_query, retrieval_result, policy_check, human_approval, decision, error, and custom.

Serialization

event.to_dict()
event.to_json()
AgentEvent.from_dict(data)

to_json() produces compact UTF-8-compatible JSON without ASCII-escaping Unicode. The allow_custom_event_types construction option is not part of the serialized event envelope.

JSON Schema

The Draft 2020-12 schema is packaged at agentlogsafe/schemas/agent-event.schema.json, available through AgentEvent.json_schema(), and published with this site at /schemas/agent-event.schema.json.

Consumers should select validation and migration behavior using schema_version, not the installed package version. New optional fields can be introduced in a future compatible schema; breaking field or meaning changes require a new schema version.