Causal Spine
Represent work as a traceable sequence from request through events to receipts.
Primitive Harness records Thread → Turn → Event → Receipt. The causal spine makes it possible to distinguish what was asked, what happened and what effect was actually recorded.
It is the trail of breadcrumbs from 'please do this' to 'this is what happened'.
The causal spine is how Primitive avoids confusing conversation with execution. A message can cause a turn; a turn can produce events; events can produce receipts. Control can add transition receipts around authority changes, creating a trace across both execution and governance.
Where this concept shows up
Execution records
The canonical Workspace runtime includes durable Thread, Turn, Event and Receipt records through Primitive Harness.
Transition records
Primitive Control's transition programme extends causal inspection to commands such as merge, spawn and revoke, with detectors for unexplained transitions or causal drift.
Why receipts matter
A plan or tool call is not equivalent to an effect. Receipts provide a durable representation of what execution boundary was crossed and what was observed.
Source lineage
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