Reference

Glossary

Terms are grouped by where they come from. Where a term is used differently in different places, the difference is stated rather than resolved by picking one meaning.

Terms

As-experienced and architecture-potential MDR

Engineering metric

Two different measures of the same thing: what one agent's own strict self-classification recorded, against what the architecture structurally guarantees regardless of which behaviour happened to trigger it first. Introduced in Experiment 3 because raw self-reports from two agents were not comparable.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Boundary

Paradigm

A crossing point between architectural responsibilities, or between the system and the outside world. Boundaries are where this research programme found most of its defects, in every experiment that looked.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Boundary Change Amplification (BCA)

Engineering metric

Boundary files, or mechanical boundary edits, per semantic decision. Measured at 4.0 files across three independent experiments in one application — and unchanged by the hardening that was expected to reduce it.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Bounded reasoning scope

Methodology

Ordo's unifying design objective: limiting how much a human or an agent must infer at once in order to make a safe change. Its causal effect on cost or correctness is an open research question, not a result.

Sourcekemiller2002/state-directed-engineering / doctrine/STATE-DIRECTED-ENGINEERING.md

Capability

Paradigm

What an actor or a state is permitted to do next. Under Ordo a capability is derived from the same predicates the transitions use as preconditions — never a second, independently maintained copy.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Change classes

Methodology

Semantic change, boundary change, mechanical propagation and presentation change. Which one a task is decides where implementation starts.

Sourcekemiller2002/state-directed-engineering / method/CHANGE-CLASSIFICATION.md

Confidence class

Evidence practice

REQUIRED, RECOMMENDED, EXPERIMENTAL, RESEARCH ONLY or DEPRECATED — how strongly a rule is held. Distinct from evidence state, which is about what supports it.

Sourcekemiller2002/state-directed-engineering / doctrine/STATE-DIRECTED-ENGINEERING.md

Construction optimisation

Methodology

Reducing how many representations or implementation locations have to exist at all. Experiment 2 produced one instance of this: making a boundary value single-sourced removed a required change site rather than mechanising its discovery.

Sourcekemiller2002/state-directed-engineering / research/theories/TH-SDE-2026-0004--detection-vs-construction-optimization.md

Context Expansion Ratio (CER)

Engineering metric

Actual context surface divided by the context a feature manifest declared, under a counting unit fixed in advance. An experimental diagnostic; never a conformance score.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Context Surface

Navigation

The state, transitions, invariants, contracts, tests, direct dependencies and composition context a change actually requires.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Detection optimisation

Methodology

Making an already-necessary change visible earlier or mechanically. Distinct from construction optimisation, and conflating the two is how a discovery improvement gets reported as a cost saving.

Sourcekemiller2002/state-directed-engineering / research/theories/TH-SDE-2026-0004--detection-vs-construction-optimization.md

Discovery Expansion

Engineering metric

Files read outside a declared feature boundary, optionally classified by whether the dependency was declared. An experimental diagnostic.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Effect

Paradigm

An externally observable consequence, requested as data rather than performed in place. This is what lets a transition be tested without the outside world.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Evidence state

Evidence practice

Supported, Provisional, Contradicted or Open — what the evidence currently says about a proposition. A contradicted row stays in the map permanently so nobody can silently re-propose it.

Sourcekemiller2002/state-directed-engineering / doctrine/EVIDENCE-TO-ENGINEERING-MAP.md

Feature manifest

Navigation

Navigation metadata declaring a feature's ownership, contracts, tests, dependencies and modification boundaries by reference. It is navigation, not semantic authority.

Sourcekemiller2002/state-directed-engineering / method/FEATURE-MANIFESTS.md

Heterogeneous verification

Verification

Using several verification mechanisms whose blind spots differ, rather than more of one. In the 2B replication, an independent reviewer's five findings had zero overlap with a 90-test suite and an adversarial self-review.

Sourcekemiller2002/state-directed-engineering / method/VERIFICATION-METHOD.md

Invariant

Paradigm

A property that must hold across every reachable state.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Legal transition

Paradigm

A change the model explicitly permits. A change the model does not permit is not a bug to be caught later; it is a thing the model does not offer.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Mechanical Discovery Rate (MDR)

Engineering metric

The proportion of required change sites a machine reported rather than a person found by looking. Experiment 3 showed it is not a proxy for cost: it fell while search and repair costs also fell.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

NOT OBSERVABLE

Evidence practice

The required label for a metric whose telemetry genuinely does not exist for the environment that produced it. Never estimated, never silently omitted. Several metrics on this site carry it.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Obligation

Paradigm

What must still happen for a transition to be complete. An obligation makes unfinished work visible in the model rather than leaving it implied.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Ordo

The public name of the methodology this site describes. In the repository that develops it, and in every research record cited here, the same methodology is called State-Directed Engineering. They are one thing under two names, not two things.

Sourcekemiller2002/state-directed-engineering / research/decisions/DF-SDE-2026-0005--adopt-ordo-as-the-public-methodology-name.md

ROS (Repository Operating System)

Operations

The operating layer this repository runs on: it governs work items, research artifact lifecycle, evidence records and validation. Ordo defines the engineering method; ROS is the process used to produce and record it.

Sourcekemiller2002/state-directed-engineering / AGENTS.md

Repository semantic map

Navigation

A small top-level index routing from major semantic areas to their locations and manifests, so navigation is deterministic rather than exploratory.

Sourcekemiller2002/state-directed-engineering / method/NAVIGATION-AND-CONTEXT.md

Representation collapse

Boundary preservation

A closed or constrained value becoming weaker or open as it crosses a boundary — a named alternative arriving on the far side as an arbitrary string.

Sourcekemiller2002/state-directed-engineering / doctrine/BOUNDARY-PRESERVATION.md

Responsibility cluster

Structural locality

A human-scale implementation grouping inside a semantic area — transitions, validation, capabilities, projections. A cluster is not automatically a separate authority.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Semantic area

Structural locality

A coherent feature, workflow or concern whose behaviour belongs together. It may span several files.

Sourcekemiller2002/state-directed-engineering / doctrine/STRUCTURAL-LOCALITY.md

Semantic authority

Structural locality

The single representation that decides a semantic fact or rule. A semantic area may span many files; its authority does not.

Sourcekemiller2002/state-directed-engineering / doctrine/STRUCTURAL-LOCALITY.md

Semantic no-op

Engineering metric

Code that compiles, satisfies architecture rules and satisfies contract checks, yet performs the wrong behaviour or none. In every trial in this programme so far, it was caught only by integration testing or direct data inspection.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Semantic state

Paradigm

A named, explicit representation of what can be true, as opposed to a combination of flags and nulls that a reader has to infer a meaning from.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

State Programming

Paradigm

The paradigm Ordo works within: explicit semantic states, legal transitions, invariants, evidence, capabilities, obligations, effects, uncertainty and boundary preservation. State Programming defines the constraints; Ordo defines how to work within them.

Sourcekemiller2002/state-directed-engineering / doctrine/STATE-PROGRAMMING.md

State-Directed Engineering (SDE)

Methodology

The name Ordo carries in the research record: the engineering methodology for building software under State Programming constraints. Research artifacts keep this name because their names are part of the experimental record.

Sourcekemiller2002/state-directed-engineering / doctrine/STATE-DIRECTED-ENGINEERING.md

Structural locality

Organisation that keeps a feature's owned state, behaviour, contracts and tests coherently bounded and composable.

Sourcekemiller2002/state-directed-engineering / doctrine/STRUCTURAL-LOCALITY.md

Uncertainty

Paradigm

A first-class explicit state for an outcome that is not yet known — distinct from null, from an exception, and from a default value. Both greenfield builds independently arrived at a four-outcome write result at the storage boundary for exactly this reason.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Uncoordinated duplication

Boundary preservation

The same fact independently maintained in two or more places with no mechanism that makes them agree. Experiment 1 found the facts outside the compiler's reach duplicated four times and twice, with no agreement check between the copies.

Sourcekemiller2002/state-directed-engineering / doctrine/BOUNDARY-PRESERVATION.md

Wire contract

Boundary preservation

The deliberately specified representation of a value crossing a boundary, as opposed to whatever a serialiser happens to emit.

Sourcekemiller2002/state-directed-engineering / doctrine/GLOSSARY.md

Also available as data

This glossary is generated from the same manifest the rest of the site is built from, and is published as JSON at /data/glossary.json alongside /data/evidence.json and /llms.txt. An agent reading the machine files and a person reading this page cannot disagree, because there is only one source.