Graph Edge

An edge is a typed, directed connection between two graph nodes. Edges are the key differentiator between Lito Graph and flat document search — they encode relationships agents can traverse.

Overview

Edges are resolved automatically from frontmatter fields during the build pipeline. When a reference can’t be resolved, it creates an unresolved: edge with a warning instead of failing the build.

Edge Categories

Structural Edges

Derived from file system hierarchy:

TypeDescriptionSource
PARENT_OFDirectory index → child pagesFolder structure
CHILD_OFChild page → directory indexFolder structure
NEXT_SECTIONSequential navigationSidebar order

Semantic Edges

Derived from concept relationships:

TypeDescriptionSource
RELATED_TOBidirectional concept linkrelated_entities field
DEPENDS_ONHard dependencyExplicit annotation
CONTAINSParent-child containmentWorkflow → StepNodes
DEPRECATED_BYSuperseded by newer versionExplicit annotation

Capability Edges

Derived from API metadata:

TypeDescriptionSource
ACTS_ONAPI operates on an entityresource field
REQUIRESPrerequisite for operationpreconditions field
EMITSProduces events/effectsside_effects field
USES_APIStep calls an APIBacktick refs in workflow steps

Procedural Edges

Derived from workflow structure:

TypeDescriptionSource
NEXT_STEP_OFSequential step chainStep ordering
ON_FAILURE_TRIGGERError recovery workflowRecovery section
ESCALATES_TOHuman escalation pathRecovery section

Edge Fields

FieldTypeDescription
sourcestringSource node ID
targetstringTarget node ID (or unresolved:Name for broken refs)
typeEdgeTypeOne of the 14 edge types above
labelstring?Human-readable label for the relationship