Decision-bearing Branches
“A decision-bearing branch is a point in the agent session at which one course of action was selected from a set of plausible alternatives, where the choice has structural, behavioural, or interpretive consequences for a future maintainer. A branch is preserved when the choice (and, where relevant, the reason for it) is recoverable from the artefact alone—commit body, code, comments, or tests.”
— Code Structure Evolution (2026), §5
Why it matters
Decision-bearing branches are the empirically observable unit of justificatory loss in the CSE probe. They translate the abstract claim of "epistemic drift" into a measurable per-edit quantity—how many deliberations entered the session, and how many survived as recoverable reasons in what was committed—giving the framework a diagnostic foothold.
Notes
The construct connects the philosophical claim to the empirical methodology of CSE. Across the seven-edit probe, sessions contain between three and six decision-bearing branches per edit; commits typically preserve only one or two. The gap between branches deliberated and branches preserved is what the proxies Structural Integrity, Invariant Preservation, and Traceability Continuity attempt to detect.
The unit is interpretive: identifying a branch requires reading the agent transcript and exercising analytical judgment about what counted as a genuine alternative. The CSE methodology exposes the per-edit ledger to permit reviewer audit precisely because the construct is not algorithmically extractable.