The engine's architectural roles each name one pattern

outcome

Define each architectural role the engine's anchors use, so the accepted set of significant units reads as a curated register of the engine's patterns and abstractions.

adapter · term.adapter line 22 · specs/protocol/role-vocabulary.sdp.md:22

Connects an external tool or runtime to an engine contract, such as a test runner or a TypeScript import reader.

codec · term.codec line 23 · specs/protocol/role-vocabulary.sdp.md:23

Parses, normalizes or encodes a representation while preserving the meaning owned by its contract, such as ids, carrier text, parameter input or source links.

contract · term.contract line 24 · specs/protocol/role-vocabulary.sdp.md:24

Owns a shared interface, data shape, closed vocabulary or public boundary that independently developed callers and providers must agree on.

decider · term.decider line 25 · specs/protocol/role-vocabulary.sdp.md:25

Computes a semantic answer from explicit inputs without reading or writing external state, such as delivery facts or example eligibility.

extractor · term.extractor line 26 · specs/protocol/role-vocabulary.sdp.md:26

Reads authored carriers or source bindings, or composes their reified results, into the graph and its located evidence.

interaction · term.interaction line 27 · specs/protocol/role-vocabulary.sdp.md:27

Adds browser controls and feedback to build-rendered content without owning its graph joins or layout. This is a corpus role for optional element behavior.

projection · term.projection line 28 · specs/protocol/role-vocabulary.sdp.md:28

Derives read-only presentation or generated contract content from the graph, the reader or an explicitly supplied answer. A page fragment and a complete page use the same role when both own presentation.

publisher · term.publisher line 29 · specs/protocol/role-vocabulary.sdp.md:29

Writes or synchronizes an owned artifact set, including its path checks, replacement, recovery and clean comparison.

index · term.index line 30 · specs/protocol/role-vocabulary.sdp.md:30

Builds a disposable lookup structure over the graph for the units that query it; it holds no authored state and is never a second read model.

reader · term.reader line 31 · specs/protocol/role-vocabulary.sdp.md:31

Answers queries over graph content, resolving or joining recorded identities and bindings without reading source files.

service · term.service line 32 · specs/protocol/role-vocabulary.sdp.md:32

Coordinates a use case or pipeline across collaborators, including execution and failure handling, while each collaborator owns its own contract.

validator · term.validator line 33 · specs/protocol/role-vocabulary.sdp.md:33

Evaluates a stated contract and reports its failures, including readiness clauses, import fidelity and corpus-selected checks. A role does not determine a Protocol validator family.

roleChoice line 37 · specs/protocol/role-vocabulary.sdp.md:37

Use the dominant responsibility of the anchored unit. A catalog of shared shapes is a contract, a table computing a semantic answer is a decider, and a failure-producing check is a validator. File size, caller count and naming style never select a role.

componentRole line 38 · specs/protocol/role-vocabulary.sdp.md:38

A component anchor's role names the dominant architectural responsibility its members serve together, read from their reviewed responsibilities rather than a count of role tokens. Omit the role when no responsibility dominates.

presentationWord line 39 · specs/protocol/role-vocabulary.sdp.md:39

Use projection for pure page, fragment and text-equivalent rendering. Use publisher for filesystem publication, codec for representation encoding and interaction for optional DOM behavior; a unit that presents uses projection, never renderer.

helperWord line 40 · specs/protocol/role-vocabulary.sdp.md:40

Choose a specific responsibility after reading the code. Graph indexes use index, concept queries use reader, parameter and path encoders use codec, browser controls use interaction and test-runtime integration uses adapter.

freeVocabulary line 41 · specs/protocol/role-vocabulary.sdp.md:41

These Model terms explain the engine's role values. Token grammar remains the only Protocol check on role, omission remains lawful, and this Model is not an adopter-wide allowlist; the self-hosting suite pins each accepted engine unit's role.

criteria

• Compare the graph's role taxonomy with these meanings and review every renamed unit against its implementation; keep an unfamiliar adopter role visible without reporting a Protocol finding.
• Check that pure presentation uses projection across the Markdown and Studio implementations, and that publication and optional browser interaction retain their distinct responsibilities.

mode

reviewed

Verifier bindings

No verifier binding recorded.

Requirement drawing

• Declared verifying examples: no declared verifying example.
• Test or oracle bindings: no recorded binding.

Decisions

• Architectural significance is annotated where it is realized

  Architectural significance is annotated on the anchor of the unit that realizes it. A code anchor may carry role, the architectural pattern the unit plays; a component: anchor may additionally carry layer, one of edge, application, domain, adapter, or infrastructure, and context, its bounded context. The component: anchor is anchored architecture: it is the declared component, and there is no separate architecture file, because the anchor sits where the component is realized. It is not the original design's declared Component that could exist before code; an unrealized component lives in Specs and never as an invented CodeNode. A role is a free, corpus-owned vocabulary whose taxonomy the census renders with counts from the graph; service, decider, projection, read-model, codec, contract, barrel, and utility are the lineage set, not a closed list. layer is a closed set, and a value outside it is an envelope error; layer or context on a non-component anchor is an envelope error. All three attributes are optional, and omission is lawful.

• impl:protocol.role-vocabulary · asserts realization of the role vocabulary in the engine anchors' pinned roles · test/self-hosting-graph.test.ts:143

  Uses

  None.

Runtime observation: not tracked.

Runtime observation: not tracked.

Build attestations: not tracked.

Deployments: not tracked.

Bills of materials: not tracked.