Glossary: Task Lineage

Mirrored from docs/design/task-lineage/references/glossary.md. Edit the source document in the repository, not this generated page.

Terms specific to the lineage system. Generic vocabulary (graph, edge, node, closure, recursive CTE, provenance) is excluded except where lineage gives a term a narrower meaning. Standard task store, knowledge graph, and ADR vocabulary lives in those features’ own glossaries; this document covers only what’s lineage-internal.

Term	Meaning
Agent memory (durable)	The framing in 1_overview.md §1: lineage exists to give discontinuous agent sessions the persistent symbol-grain context that human engineers carry in their heads. The biography surface is the read shape; the edge store is the substrate.
Bipartite bridge	The structural commitment that the task graph and the code knowledge graph are one graph with two node types, not two graphs that reference each other. See 2_design.md §4, 4_decisions.md ADR-007.
Biography closure	The closure operation (orbit.lineage.biography) that returns a rendered prose narrative for a code selector, alongside the structured feature payload. The headline read surface of the minimal Phase 1. See 2_design.md §5.2, §6.
Closure	A named, opinionated graph-traversal projection. The minimal Phase 1 surface is feature and biography; additional closures are deferred. See 2_design.md §5.
Confidence	Per-edge score in [0, 1] indicating derivation strength. Declared edges are 1.0; derived edges score by signal source. See 2_design.md §2.3.
Co-touches edge	An edge between two tasks that share at least one file in context_files or commit attribution. The default file-grain edge.
Co-touches-symbol edge	A stronger version of co-touches that requires shared knowledge-graph node attribution rather than file-level overlap.
Declared edge	An edge whose source is declared — set explicitly by a human or agent, not inferred from a deriver. Confidence 1.0 by definition.
Derivation cursor	Per-deriver watermark stored in derivation_cursors, used to make the derivation pipeline incremental. See 2_design.md §2.4.
Derivation source	One of commit-grep, kg-attribution, task-text, declared (minimal Phase 1). Stamped on every edge for provenance. Additional sources are deferred.
Derived edge	Any edge whose source is not declared. The dominant edge category by ADR-003 design.
Deterministic renderer	The Phase 1 biography renderer, which pulls strings from canonical fields and arranges them per a fixed grammar derived from the edge taxonomy — no LLM in the path. Auditable line-by-line. See 4_decisions.md ADR-009, 2_design.md §6.2.
Edge type	One of the typed relationships in 2_design.md §1.1. The system’s causal vocabulary; also the grammar of the biography. The minimal Phase 1 ships 7 task-task and 4 task-code types; others are named-and-deferred.
Evidence	The JSON payload stored on each edge that names the original source row, line range, commit SHA, or ADR section that justified the derivation. See 2_design.md §1.2.
Feature closure	The closure operation that takes a code selector and returns all attributed tasks chronologically; the structured substrate the biography renderer consumes. See 2_design.md §5.1.
Open concerns	Distinct from “honest limitations.” The §9 list in 2_design.md of unresolved items the minimal Phase 1 has not yet decided on, ordered by ship-blocking priority — to be addressed one by one as follow-up tasks.
Oral history (for agents)	The metaphor in 1_overview.md §1.3: institutional context that humans pass informally and remember continuously is, for agents, replaced by symbol biographies attached to KG nodes and surfaced automatically on artifact load.
Orphan biography	A biography keyed on a KG stable_id that no longer survives the structural change it was meant to outlive (extract-into-multiple, inline-into-caller, cross-language port, wholesale rewrite). The renderer surfaces orphan cases via a footnote. See 2_design.md §7.
Symbol biography	The rendered narrative attached to a KG node — chronologically-ordered, edge-typed, deterministic-templated. The headline read surface of the minimal Phase 1. See 2_design.md §6, 4_decisions.md ADR-008.
Symbol identity stability	The load-bearing assumption that KG stable_id survives the structural changes lineage is meant to outlive. Named explicitly so it can be challenged; failure modes documented in 2_design.md §7, 4_decisions.md ADR-010.
Task-code edge	An edge in task_code_edges between a task node and a code-graph node. Distinct from task-task edges in task_edges.
Verb upgrade	The task-text deriver’s mechanism for promoting a default references edge to a typed edge (supersedes, extends, reverts, motivates) when an adjacent verb in the source text matches an upgrade rule. The renderer’s primary source of narrative verbs; ship-blocking eval set in 2_design.md §9.1. See 2_design.md §2.2.