Entities

The base has 10 tables and 189 fields. Six native tables describe the systems. Four mirrors bring in the people, organizations, tools and tags those descriptions link to.

Table	Fields	Documentation	Ownership
System	21	Open reference	Systems Central
Record Type	10	Open reference	Systems Central
System Rule	12	Open reference	Systems Central
Architecture Decision	17	Open reference	Systems Central
Work Item	20	Open reference	Systems Central
Feedback	32	Open reference	Systems Central
Membership (mirror)	25	Open reference	Core
Organization (mirror)	27	Open reference	Core
Tool (mirror)	13	Open reference	Tooling and Access
Tags (mirror)	12	Open reference	Core

How the native tables connect

System is the hub. Every other native table links to it:

• Record Type → System twice: System of Record (exactly one) and Mirrored In (many).
• System Rule → System (where the rule holds), → Record Type through Applies To and → Architecture Decision through Based On ADR.
• Architecture Decision → System and Record Type, and → itself through Supersedes / Superseded By.
• Work Item → System, Record Type, System Rule and Architecture Decision, plus Blocked By / Blocks between Work Items.
• Feedback → System (one system per report).

Each of those links has an inverse column on the other side, which is read only by convention: change the link on the row that owns it, as named in each reference page.

Cardinality and identifiers

Only Record Type → System of Record is configured as a single-record link. Every other link allows several records, even where the description asks for exactly one (Feedback → System, System → Maintainer, Feedback → Reporter (Membership) and Accountable). The picker does not enforce those limits; people do. Use names to cite rows: System Name, Record Type Name, rule Name, Architecture Decision Name (ADR-NNNN · Title) and Work Item Title. Airtable record IDs are local to this base.