Reserved identifiers

Some names and prefixes are reserved by ScaiLog and rejected if you try to use them as your own field names, call-site ids, subjects, or tenants. They come from constants.py and the spec's Annex B. This page lists all of them plus the call_site_id format, so you can name your own fields and sites without colliding.

Reserved top-level entry field names#

These names are the wire keys ScaiLog uses for the entry envelope, so you cannot use them as your own structured field names — an entry that does is rejected with RESERVED_FIELD:

event_id, tenant, service, env, site, level, ts, msg, fields, pi, subject, trace_id, request_id.

Put your own structured data inside fields (or mark PI with pi()); the reserved names above are the envelope around it.

Reserved call-site prefixes#

Two prefixes are reserved on call_site_id values and cannot be used by application code:

SCAILOG-* — ScaiLog's own components use these for their internal call sites.
AUTO-* — the SDK derives these as a fallback when code emits a log without a developer-assigned call_site_id (an AUTO-<hash> id from the module, function, and line). Treat an AUTO-* site as a to-do: graduate it to a named, declared site. scailog sites --diff flags them.

Both prefixes are accepted from the components/SDK that own them but are not valid for you to author, and the CI validator (scailog-ci) rejects them in your source.

The `call_site_id` format#

A developer-assigned call_site_id must match this regular expression:

maxima
^[A-Z0-9]+(-[A-Z0-9]+){2,}$

That is: uppercase letters and digits only, in at least three hyphen-joined segments — conceptually <PRODUCT>-<MODULE>-<EVENT>-.... For example BILLING-CHARGE-CAPTURED is valid; billing-charge (lowercase, only two segments) is not. The same pattern is enforced by the SDK at emit time, by the server at ingest, and by scailog-ci at build time.

Reserved subject#

_service — the reserved data subject for PI-like fields that belong to no natural person (for example a service account's own identifiers). It is not a real data subject and is handled distinctly from person subjects.

Reserved tenant#

default — the reserved default tenant. It is the fallback tenant for the SDK, agent, CLI, and audit job when none is configured.