ADR 0005: Activity-based provenance

• Status: Accepted

• Date: 2026-09-19

Decision

Production provenance is stored as activities with representation input and output edges. Activity kinds and edge roles are extensible identifiers. An activity may record tool and agent identity, while parameters use the metadata model.

Derived lineage is a traversal query, not the sole stored fact. Generation cycles are rejected, fan-in/fan-out and cross-asset processing are supported, and malformed persisted cycles produce bounded errors.

Activities are complete facts in the current model: they may have no inputs, but must have at least one output because no in-progress lifecycle is exposed. Identical edges and a representation appearing on both sides are rejected. Timestamps, tool identity, agent identity, and edge roles are optional and bounded. Metadata assertions carry activity parameters.

SQLite schema version 2 stores activities and their edges. Creation and cycle validation occur inside the surrounding production transaction. Read APIs return deterministically ordered activities and support producing/consuming lookup plus transitive ancestor/descendant traversal.

Consequences

The model maps strongly at a conceptual level to W3C PROV activities and entities and accommodates MovieLabs OMC concepts without claiming compliance or inferring revision/variant semantics.