a13n Logging

a13n-logging is the shared logging library for Agent Foundation. The distribution is a13n-logging; the import package is a13n_logging. It requires Python 3.13 and uses standard logging plus Rich.

Use it

from a13n_logging import LogFormat, configure_logging, get_logger

configure_logging(
    log_format=LogFormat.json,
    logger_names=("my_application",),
)
get_logger("my_application.tasks").info("ready", extra={"task_id": "task-example"})

Configure once at the executable boundary. Libraries only create namespaced loggers. JSON goes to stdout; LogFormat.pretty selects Rich terminal rendering, and a LogFile adds a size-rotated JSON file. log_context(**fields) binds fields to every record logged in a block. No logger namespace or root logger is configured by default, and this package does not redact secret values.

The Logging guide documents the public exports, configuration defaults, bound fields and their precedence, file rotation, exception behavior, output ownership, and customization.

Validate

uv run --locked pytest packages/a13n-logging/tests

Release boundary

a13n-logging publishes independently through release/a13n-logging-v<version>. Service and Harness releases consume it but do not republish it. See the repository release model.