Tighten evidence context source excerpts

Document evidence context source unit excerpts
Update evidence context output coverage
2026-08-09 20:04:46 +00:00 · 2026-08-09 19:47:27 +00:00 · 2026-08-09 19:45:21 +00:00 · 2026-08-09 19:42:33 +00:00
18 changed files with 290 additions and 718 deletions
--- a/docs/config.md
+++ b/docs/config.md
@@ -319,7 +319,8 @@ Unknown outer or nested option fields are rejected, as are incompatible YAML
 types. The allowlist remains valid when a run uses lane filtering: a configured
 lane that is not active for that invocation simply contributes no evidence.
 Evidence publication is opt-in because it can persist source text and metadata.
-Its payload contract is [Published Evidence Context](integrations/evidence-context.md).
+When enabled, it publishes the selected source-unit excerpt defined by the
+[Published Evidence Context contract](integrations/evidence-context.md).

 ## References And Ordered Handoffs

--- a/docs/consumers/subprocess.md
+++ b/docs/consumers/subprocess.md
@@ -55,10 +55,10 @@ contract. The JSON bundle contract links to the available lane contracts.
 If `index.json` has an `evidence_context` descriptor, treat it as a
 pipeline-wide artifact rather than a lane entry. Verify its six descriptor
 fields before decoding the linked file according to the [Published Evidence
-Context contract](../integrations/evidence-context.md). Use each
-`evidence_refs` entry as the citation to source material. Its surrounding
-context range and included units explain the citation, but do not widen or
-replace the cited source reference.
+Context contract](../integrations/evidence-context.md). Decode its top-level
+source-unit array as a reading excerpt. Obtain authoritative citations and lane
+provenance from the normalized lane artifacts; the excerpt has neither and its
+nearby units do not widen a lane artifact's cited source reference.

 A zero exit status may still report rejected outputs, warnings, or absent
 lanes. The caller decides which lane IDs are required for its own work and
@@ -73,5 +73,5 @@ them. Treat the input, output bundle, cache, debug bundle, and captured process
 logs as potentially sensitive data. Apply the caller's access controls and
 retention policy, and avoid copying secrets into arguments, logs, or
 provenance records. An evidence-context artifact contains source-unit text and
-metadata, and selected lanes can cover most of an input; preserve and share it
-only when that source content is authorized for the recipient.
+metadata and can cover most of an input; preserve and share it only when that
+source content is authorized for the recipient.
--- a/docs/integrations/evidence-context.md
+++ b/docs/integrations/evidence-context.md
@@ -1,9 +1,11 @@
 # Published Evidence Context

 This contract defines the optional `source/evidence-context` artifact emitted
-by the production JSON output. Its configuration is owned by
-[Configuration](../config.md#module-bindings-and-validators); its logical-file
-discovery is owned by [Published JSON Output](json-output.md).
+by the production JSON output. It is a selected source-unit excerpt for
+convenient reading alongside normalized lane artifacts; it is not a second
+citation or provenance model. Its configuration is owned by
+[Configuration](../config.md#module-bindings-and-validators), and its
+logical-file discovery is owned by [Published JSON Output](json-output.md).

 ## Identity And Discovery

@@ -26,91 +28,80 @@ its absence means evidence publication was not enabled for that bundle.

 ## Payload

-The v1 payload is a JSON object with required `source_id`, `source_digest`,
-`window_units`, `selected_lanes`, and `contexts` fields. `selected_lanes` and
-`contexts` are always arrays; an enabled configuration with no accepted direct
-evidence publishes `contexts: []`.
+The v1 payload is a top-level JSON array of generic source units. There is no
+wrapper, source-level metadata, context grouping, lane identifier, or evidence
+reference in the payload. An enabled configuration with no contributing
+accepted evidence publishes `[]`.

 ```json
-{
-  "source_id": "session-alpha",
-  "source_digest": "sha256:0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef",
-  "window_units": 1,
-  "selected_lanes": ["npc_registry", "spells"],
-  "contexts": [
-    {
-      "context_ref": {
-        "source_id": "session-alpha",
-        "start_unit_id": 10,
-        "end_unit_id": 20
-      },
-      "evidence_refs": [
-        {
-          "lane_id": "spells",
-          "source_ref": {
-            "source_id": "session-alpha",
-            "start_unit_id": 10,
-            "end_unit_id": 10
-          }
-        }
-      ],
-      "units": [
-        {
-          "id": 10,
-          "kind": "transcript_segment",
-          "text": "Aria casts Cure Wounds.",
-          "ref": {
-            "source_id": "session-alpha",
-            "start_unit_id": 10,
-            "end_unit_id": 10
-          }
-        },
-        {
-          "id": 20,
-          "kind": "transcript_segment",
-          "text": "The party regroups.",
-          "ref": {
-            "source_id": "session-alpha",
-            "start_unit_id": 20,
-            "end_unit_id": 20
-          }
-        }
-      ]
+[
+  {
+    "id": 10,
+    "kind": "transcript_segment",
+    "text": "Aria casts Cure Wounds.",
+    "ref": {
+      "source_id": "session-alpha",
+      "start_unit_id": 10,
+      "end_unit_id": 10
    }
-  ]
-}
+  },
+  {
+    "id": 20,
+    "kind": "transcript_segment",
+    "text": "The party regroups.",
+    "ref": {
+      "source_id": "session-alpha",
+      "start_unit_id": 20,
+      "end_unit_id": 20
+    }
+  }
+]
 ```

-Each context requires a `context_ref` object and `evidence_refs` and `units`
-arrays. `context_ref` identifies the first and last included unit. Each
-evidence entry contains a selected `lane_id` and an original `source_ref`. A
-unit uses the existing source-unit shape: required `id`, `kind`, `text`, and
-self `ref`, plus optional JSON-object `metadata`. Fixed payload objects reject
-unknown fields; unit metadata may contain application-defined JSON values.
+Each source unit has required `id`, `kind`, `text`, and self `ref` fields.
+`ref` contains `source_id`, `start_unit_id`, and `end_unit_id`, and both unit
+endpoints identify that unit's `id`. A unit may also contain source-owned
+`metadata`, an open-ended JSON object. Fixed unit and reference fields are
+strict: consumers must reject unknown fixed fields, malformed units, invalid
+self-references, units whose `source_id` differs from other units in the same
+excerpt, and a payload that is not the array described here.

-## Citations And Context
+The excerpt preserves each selected unit exactly as represented by the
+validated generic source document. It does not add evidence-context-specific
+annotations or reshape source-owned metadata.

-`evidence_refs` are the authoritative citations. They identify the direct
-references emitted by accepted normalized artifacts. `context_ref` and the
-units collection include those cited units plus nearby source units selected by
-the configured window. They are explanatory context, not widened citations.
+## Selection And Citations

-Only accepted outputs from the configured lane allowlist contribute. Rejected,
-failed, absent, and lane-filtered outputs do not contribute. The artifact never
-contains raw input bytes, prompts, model responses, auxiliary reference
-content, credentials, or filesystem paths.
+The framework obtains direct source references only through typed evidence
+projections of accepted normalized artifacts in the configured lane allowlist.
+It validates each reference against the current source document, expands its
+range by `window_units` source-unit positions on each side, clamps at document
+boundaries, and takes the union of all expanded ranges. The output contains
+each selected source unit once in source-document position order, regardless
+of numeric unit IDs. Repeated references, overlapping windows, and citations
+from multiple lanes do not duplicate a unit. Rejected, failed, absent,
+inactive, and unselected lanes contribute nothing.

-## Ordering And Compatibility
+Normalized lane artifacts remain authoritative for citations and for which lane
+cited a range. The excerpt has no lane attribution and must not be used to
+reconstruct it. Its included nearby units provide reading context only; they
+do not widen any citation in a lane artifact.

-The selected lane allowlist is lexical. Contexts and units are in source
-document position order, not numeric unit-ID order. Direct evidence entries
-are deterministically ordered by lane and source reference. Overlapping or
-contiguous windows merge, and each source unit appears at most once in the
-resulting contexts.
+The excerpt contains at most every generic source unit once. It can therefore
+equal the complete generic source document when coverage is broad or the
+window is large. No byte-, token-, or compression-size guarantee is made, and
+the framework does not truncate the excerpt to meet an arbitrary size limit.
+
+## Consumer Responsibilities And Data Handling

 The artifact is additive to the JSON bundle and is not a lane payload,
 normalized-output count, checkpoint, or generated reference. Consumers that
-do not need it must tolerate the absent optional descriptor. Consumers that do
-use it should preserve the artifact and its schema identity with the run
-provenance, and should treat its source text and metadata as sensitive durable
-content.
+do not need it must tolerate an absent descriptor. Consumers that do use it
+should validate the descriptor and payload before use, retain the artifact with
+its schema identity when needed for a run record, and read citations from the
+corresponding normalized lane artifacts.
+
+The excerpt contains source-unit text and source-owned metadata and is durable
+output. Treat it as sensitive source content, apply appropriate access controls
+and retention, and do not assume its selected form is materially smaller or
+less sensitive than the original input.
--- a/docs/integrations/json-output.md
+++ b/docs/integrations/json-output.md
@@ -24,7 +24,7 @@ root for the logical discovery described here.
 | `warnings.json` | Accepted-output and run warnings. |
 | `lanes/<safe-lane-id>.json` | One normalized artifact payload for each lane. |
 | `chunk-map.json` | Optional accepted chunk map, when its export is enabled and available. |
-| `evidence-context.json` | Optional source-context artifact, when evidence publication is enabled. |
+| `evidence-context.json` | Optional selected source-unit excerpt, when evidence publication is enabled. |

 JSON files are pretty-printed with a trailing newline. Lane payloads are
 accepted only when their media type is `application/json`.
--- a/docs/internal/modules.md
+++ b/docs/internal/modules.md
@@ -42,7 +42,8 @@ generic source references and must use the codec's exact Go type. It does not
 interpret surrounding context or publish files; the pipeline validates the
 capability during preparation and the output boundary owns publication. See
 the [Published Evidence Context contract](../integrations/evidence-context.md)
-for the durable result.
+for the durable source-unit excerpt. Lane artifacts retain citation and lane
+provenance; the framework does not add either to that published excerpt.

 An artifact family is broader than a module: it owns the cohesive domain
 feature across its artifact type, codec, stage modules, validators, prompt
--- a/docs/operations.md
+++ b/docs/operations.md
@@ -110,9 +110,9 @@ are defined in [Accepted Chunk Map](integrations/chunk-map.md). An optional
 [evidence context](integrations/evidence-context.md) contains source-unit text
 and metadata. It is not a cache or debug artifact: retain it with the output
 bundle only for as long as consumers need it, and apply source-content access
-controls to the entire bundle. Selected lanes may collectively cite most of a
-transcript, so a broad allowlist can make the evidence artifact nearly as
-sensitive and large as the source itself.
+controls to the entire bundle. Its selected source-unit excerpt may include
+every source unit once when coverage is broad or its configured window is
+large, so do not assume a byte or token reduction or reduced sensitivity.

 ## Chunk-Plan Cache

--- a/internal/cli/dnd_enemy_events_contract_test.go
+++ b/internal/cli/dnd_enemy_events_contract_test.go
@@ -189,10 +189,18 @@ func TestMaintainedCompleteExamplePublishesRegistryBackedEntityOccurrences(t *te
 	}

 	evidence := readProductionJSON[evidencecontext.Document](t, filepath.Join(runRoot, "evidence-context.json"))
-	for _, laneID := range []string{"enemy-events", "npc-registry", "npc-occurrences", "item-registry", "item-occurrences", "location-registry", "location-occurrences"} {
-		if !containsString(evidence.SelectedLanes, laneID) || !evidenceHasLane(evidence, laneID) {
-			t.Fatalf("evidence context = %#v, want direct %s evidence", evidence, laneID)
+	if len(evidence) == 0 {
+		t.Fatalf("evidence context = %#v, want selected source-unit evidence", evidence)
+	}
+	seenEvidenceUnits := make(map[int]struct{}, len(evidence))
+	for _, unit := range evidence {
+		if unit.Ref.SourceID != "session-ravenfall" || unit.Ref.StartUnitID != unit.ID || unit.Ref.EndUnitID != unit.ID {
+			t.Fatalf("evidence unit = %#v, want unchanged source-unit self-reference", unit)
 		}
+		if _, exists := seenEvidenceUnits[unit.ID]; exists {
+			t.Fatalf("evidence context = %#v, want each source unit once", evidence)
+		}
+		seenEvidenceUnits[unit.ID] = struct{}{}
 	}

 	requests := client.requestsFor(enemyevents.PromptID)
@@ -415,17 +423,6 @@ func containsString(values []string, want string) bool {
 	return false
 }

-func evidenceHasLane(value evidencecontext.Document, laneID string) bool {
-	for _, context := range value.Contexts {
-		for _, reference := range context.EvidenceRefs {
-			if reference.LaneID == laneID {
-				return true
-			}
-		}
-	}
-	return false
-}
-
 func generatedReferenceBinding(bindings []pipeline.ReferenceBinding, slotName string) (pipeline.ReferenceBinding, bool) {
 	for _, binding := range bindings {
 		if binding.SlotName == slotName && binding.Artifact != nil {
--- a/internal/framework/evidencecontext/assets/schemas/source_evidence_context.v1.json
+++ b/internal/framework/evidencecontext/assets/schemas/source_evidence_context.v1.json
@@ -2,24 +2,8 @@
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "notarius.source.evidence_context",
  "title": "notarius_source_evidence_context_v1",
-  "type": "object",
-  "additionalProperties": false,
-  "required": ["source_id", "source_digest", "window_units", "selected_lanes", "contexts"],
-  "properties": {
-    "source_id": {"type": "string", "minLength": 1},
-    "source_digest": {"type": "string", "pattern": "^sha256:[0-9a-f]{64}$"},
-    "window_units": {"type": "integer", "minimum": 0},
-    "selected_lanes": {
-      "type": "array",
-      "minItems": 1,
-      "uniqueItems": true,
-      "items": {"type": "string", "minLength": 1}
-    },
-    "contexts": {
-      "type": "array",
-      "items": {"$ref": "#/$defs/context"}
-    }
-  },
+  "type": "array",
+  "items": {"$ref": "#/$defs/unit"},
  "$defs": {
    "source_ref": {
      "type": "object",
@@ -42,25 +26,6 @@
        "ref": {"$ref": "#/$defs/source_ref"},
        "metadata": {"type": "object", "additionalProperties": true}
      }
-    },
-    "evidence_ref": {
-      "type": "object",
-      "additionalProperties": false,
-      "required": ["lane_id", "source_ref"],
-      "properties": {
-        "lane_id": {"type": "string", "minLength": 1},
-        "source_ref": {"$ref": "#/$defs/source_ref"}
-      }
-    },
-    "context": {
-      "type": "object",
-      "additionalProperties": false,
-      "required": ["context_ref", "evidence_refs", "units"],
-      "properties": {
-        "context_ref": {"$ref": "#/$defs/source_ref"},
-        "evidence_refs": {"type": "array", "minItems": 1, "items": {"$ref": "#/$defs/evidence_ref"}},
-        "units": {"type": "array", "minItems": 1, "items": {"$ref": "#/$defs/unit"}}
-      }
    }
  }
 }
--- a/internal/framework/evidencecontext/build.go
+++ b/internal/framework/evidencecontext/build.go
@@ -3,118 +3,62 @@ package evidencecontext
 import (
 	"fmt"
 	"sort"
-	"strings"

 	"gitea.maximumdirect.net/eric/notarius/internal/core/source"
 )

-type contribution struct {
-	laneID   string
-	ref      source.SourceRef
+type expandedRange struct {
 	startPos int
 	endPos   int
 }

-type expandedRange struct {
-	startPos      int
-	endPos        int
-	contributions []contribution
-}
-
-// Build validates accepted direct references, expands them by source-document
-// position, and returns their deterministic context union.
+// Build validates projected source references, expands them by source-document
+// position, and returns their ordered union as an owned source-unit excerpt.
 func Build(request BuildRequest) (Document, error) {
 	if request.WindowUnits < 0 {
-		return Document{}, fmt.Errorf("window_units must not be negative")
-	}
-	lanes, err := normalizeSelectedLanes(request.SelectedLanes)
-	if err != nil {
-		return Document{}, err
+		return nil, fmt.Errorf("window_units must not be negative")
 	}
 	if err := source.ValidateDocument(request.Source); err != nil {
-		return Document{}, fmt.Errorf("validate source document: %w", err)
+		return nil, fmt.Errorf("validate source document: %w", err)
 	}
 	digest, err := source.DigestDocument(request.Source)
 	if err != nil {
-		return Document{}, fmt.Errorf("digest source document: %w", err)
+		return nil, fmt.Errorf("digest source document: %w", err)
 	}
 	if digest != request.Source.Digest {
-		return Document{}, fmt.Errorf("source digest does not match source document digest")
+		return nil, fmt.Errorf("source digest does not match source document digest")
 	}

-	selected := make(map[string]struct{}, len(lanes))
-	for _, laneID := range lanes {
-		selected[laneID] = struct{}{}
-	}
 	index := source.NewDocumentIndex(request.Source)
-	seen := make(map[evidenceKey]struct{})
-	contributions := make([]contribution, 0)
-	for laneIndex, laneEvidence := range request.LaneEvidence {
-		laneID := strings.TrimSpace(laneEvidence.LaneID)
-		if _, ok := selected[laneID]; !ok {
-			return Document{}, fmt.Errorf("lane evidence[%d] lane %q is not selected", laneIndex, laneID)
+	ranges := make([]expandedRange, 0, len(request.SourceRefs))
+	for refIndex, ref := range request.SourceRefs {
+		if err := index.ValidateRef(ref); err != nil {
+			return nil, fmt.Errorf("source reference[%d]: %w", refIndex, err)
 		}
-		for refIndex, ref := range laneEvidence.SourceRefs {
-			if err := index.ValidateRef(ref); err != nil {
-				return Document{}, fmt.Errorf("lane %q source reference[%d]: %w", laneID, refIndex, err)
+		startPos, _ := index.Position(ref.StartUnitID)
+		endPos, _ := index.Position(ref.EndUnitID)
+		ranges = append(ranges, expandedRange{
+			startPos: expandStart(startPos, request.WindowUnits),
+			endPos:   expandEnd(endPos, len(request.Source.Units), request.WindowUnits),
+		})
+	}
+
+	merged := mergeRanges(ranges)
+	unitCount := 0
+	for _, value := range merged {
+		unitCount += value.endPos - value.startPos + 1
+	}
+	document := make(Document, 0, unitCount)
+	for _, value := range merged {
+		for position := value.startPos; position <= value.endPos; position++ {
+			unit, err := cloneSourceUnit(request.Source.Units[position])
+			if err != nil {
+				return nil, fmt.Errorf("clone source unit at position %d: %w", position, err)
 			}
-			key := evidenceKey{laneID: laneID, ref: ref}
-			if _, exists := seen[key]; exists {
-				continue
-			}
-			seen[key] = struct{}{}
-			startPos, _ := index.Position(ref.StartUnitID)
-			endPos, _ := index.Position(ref.EndUnitID)
-			contributions = append(contributions, contribution{laneID: laneID, ref: ref, startPos: expandStart(startPos, request.WindowUnits), endPos: expandEnd(endPos, len(request.Source.Units), request.WindowUnits)})
+			document = append(document, unit)
 		}
 	}
-
-	sort.Slice(contributions, func(i, j int) bool { return lessContribution(contributions[i], contributions[j]) })
-	document := Document{
-		SourceID:      request.Source.ID,
-		SourceDigest:  digest,
-		WindowUnits:   request.WindowUnits,
-		SelectedLanes: lanes,
-		Contexts:      make([]Context, 0),
-	}
-	for _, rangeValue := range mergeRanges(contributions) {
-		context, err := buildContext(request.Source, rangeValue)
-		if err != nil {
-			return Document{}, err
-		}
-		document.Contexts = append(document.Contexts, context)
-	}
-	canonical, err := canonicalizeOwned(document)
-	if err != nil {
-		return Document{}, fmt.Errorf("validate evidence context: %w", err)
-	}
-	return canonical, nil
-}
-
-type evidenceKey struct {
-	laneID string
-	ref    source.SourceRef
-}
-
-func normalizeSelectedLanes(values []string) ([]string, error) {
-	if len(values) == 0 {
-		return nil, fmt.Errorf("selected_lanes must not be empty")
-	}
-	seen := make(map[string]struct{}, len(values))
-	lanes := make([]string, 0, len(values))
-	for index, raw := range values {
-		laneID := strings.TrimSpace(raw)
-		if laneID == "" {
-			return nil, fmt.Errorf("selected_lanes[%d] must not be empty", index)
-		}
-		if _, exists := seen[laneID]; exists {
-			return nil, fmt.Errorf("selected_lanes lane %q is duplicated", laneID)
-		}
-		seen[laneID] = struct{}{}
-		lanes = append(lanes, laneID)
-	}
-	sort.Strings(lanes)
-	return lanes, nil
+	return document, nil
 }

 func expandStart(position, window int) int {
@@ -132,65 +76,25 @@ func expandEnd(position, length, window int) int {
 	return position + window
 }

-func lessContribution(left, right contribution) bool {
-	if left.startPos != right.startPos {
-		return left.startPos < right.startPos
-	}
-	if left.endPos != right.endPos {
-		return left.endPos < right.endPos
-	}
-	return lessEvidenceRef(EvidenceRef{LaneID: left.laneID, SourceRef: left.ref}, EvidenceRef{LaneID: right.laneID, SourceRef: right.ref})
-}
-
-func mergeRanges(values []contribution) []expandedRange {
+func mergeRanges(values []expandedRange) []expandedRange {
 	if len(values) == 0 {
 		return nil
 	}
-	ranges := make([]expandedRange, 0, len(values))
+	sort.Slice(values, func(i, j int) bool {
+		if values[i].startPos != values[j].startPos {
+			return values[i].startPos < values[j].startPos
+		}
+		return values[i].endPos < values[j].endPos
+	})
+	merged := make([]expandedRange, 0, len(values))
 	for _, value := range values {
-		if len(ranges) == 0 || value.startPos > ranges[len(ranges)-1].endPos+1 {
-			ranges = append(ranges, expandedRange{startPos: value.startPos, endPos: value.endPos, contributions: []contribution{value}})
+		if len(merged) == 0 || value.startPos > merged[len(merged)-1].endPos+1 {
+			merged = append(merged, value)
 			continue
 		}
-		current := &ranges[len(ranges)-1]
-		if value.endPos > current.endPos {
-			current.endPos = value.endPos
+		if value.endPos > merged[len(merged)-1].endPos {
+			merged[len(merged)-1].endPos = value.endPos
 		}
-		current.contributions = append(current.contributions, value)
 	}
-	return ranges
-}
-
-func buildContext(document *source.SourceDocument, value expandedRange) (Context, error) {
-	evidenceRefs := make([]EvidenceRef, 0, len(value.contributions))
-	for _, contribution := range value.contributions {
-		evidenceRefs = append(evidenceRefs, EvidenceRef{LaneID: contribution.laneID, SourceRef: contribution.ref})
-	}
-	sort.Slice(evidenceRefs, func(i, j int) bool { return lessEvidenceRef(evidenceRefs[i], evidenceRefs[j]) })
-	units := make([]source.SourceUnit, 0, value.endPos-value.startPos+1)
-	for position := value.startPos; position <= value.endPos; position++ {
-		unit, err := cloneSourceUnit(document.Units[position])
-		if err != nil {
-			return Context{}, fmt.Errorf("clone source unit at position %d: %w", position, err)
-		}
-		units = append(units, unit)
-	}
-	return Context{
-		ContextRef:   source.SourceRef{SourceID: document.ID, StartUnitID: units[0].ID, EndUnitID: units[len(units)-1].ID},
-		EvidenceRefs: evidenceRefs,
-		Units:        units,
-	}, nil
-}
-
-func lessEvidenceRef(left, right EvidenceRef) bool {
-	if left.LaneID != right.LaneID {
-		return left.LaneID < right.LaneID
-	}
-	if left.SourceRef.SourceID != right.SourceRef.SourceID {
-		return left.SourceRef.SourceID < right.SourceRef.SourceID
-	}
-	if left.SourceRef.StartUnitID != right.SourceRef.StartUnitID {
-		return left.SourceRef.StartUnitID < right.SourceRef.StartUnitID
-	}
-	return left.SourceRef.EndUnitID < right.SourceRef.EndUnitID
+	return merged
 }
--- a/internal/framework/evidencecontext/codec.go
+++ b/internal/framework/evidencecontext/codec.go
@@ -6,7 +6,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"regexp"
 	"strings"
 	"sync"

@@ -18,8 +17,6 @@ import (
 //go:embed assets/schemas/source_evidence_context.v1.json
 var schemaAssets embed.FS

-var digestPattern = regexp.MustCompile(`^sha256:[0-9a-f]{64}$`)
-
 var (
 	loadSchemaOnce sync.Once
 	loadedSchema   []byte
@@ -78,24 +75,24 @@ func (c *Codec) Encode(value Document) ([]byte, error) {

 func (c *Codec) Decode(content []byte) (Document, error) {
 	if _, err := c.schemaBytes(); err != nil {
-		return Document{}, err
+		return nil, err
 	}
 	if err := validateSchemaInstance(content); err != nil {
-		return Document{}, fmt.Errorf("decode evidence context: %w", err)
+		return nil, fmt.Errorf("decode evidence context: %w", err)
 	}
 	decoder := json.NewDecoder(bytes.NewReader(content))
 	decoder.DisallowUnknownFields()
 	var value Document
 	if err := decoder.Decode(&value); err != nil {
-		return Document{}, fmt.Errorf("decode evidence context: %w", err)
+		return nil, fmt.Errorf("decode evidence context: %w", err)
 	}
 	var trailing any
 	if err := decoder.Decode(&trailing); err != io.EOF {
-		return Document{}, fmt.Errorf("decode evidence context: multiple JSON values")
+		return nil, fmt.Errorf("decode evidence context: multiple JSON values")
 	}
 	canonical, err := canonicalizeOwned(value)
 	if err != nil {
-		return Document{}, fmt.Errorf("decode evidence context: %w", err)
+		return nil, fmt.Errorf("decode evidence context: %w", err)
 	}
 	return canonical, nil
 }
@@ -115,17 +112,16 @@ func loadAndCompileSchema() {
 		return
 	}
 	var identity struct {
-		ID       string   `json:"$id"`
-		Title    string   `json:"title"`
-		Type     string   `json:"type"`
-		Required []string `json:"required"`
+		ID    string `json:"$id"`
+		Title string `json:"title"`
+		Type  string `json:"type"`
 	}
 	if err := json.Unmarshal(raw, &identity); err != nil {
 		loadSchemaErr = fmt.Errorf("decode source evidence context schema: %w", err)
 		return
 	}
-	if identity.ID != SchemaID || identity.Title != SchemaName || identity.Type != "object" || !hasRequiredFields(identity.Required) {
-		loadSchemaErr = fmt.Errorf("source evidence context schema identity or required fields are invalid")
+	if identity.ID != SchemaID || identity.Title != SchemaName || identity.Type != "array" {
+		loadSchemaErr = fmt.Errorf("source evidence context schema identity is invalid")
 		return
 	}
 	schemaDocument, err := jsonschema.UnmarshalJSON(bytes.NewReader(raw))
@@ -158,164 +154,65 @@ func validateSchemaInstance(content []byte) error {
 	return nil
 }

-func hasRequiredFields(required []string) bool {
-	want := map[string]bool{"source_id": true, "source_digest": true, "window_units": true, "selected_lanes": true, "contexts": true}
-	for _, field := range required {
-		delete(want, field)
-	}
-	return len(want) == 0
-}
-
 func canonicalize(value Document) (Document, error) {
 	owned, err := clone(value)
 	if err != nil {
-		return Document{}, err
+		return nil, err
 	}
 	return canonicalizeOwned(owned)
 }

 func canonicalizeOwned(value Document) (Document, error) {
-	if err := requireIdentity("source_id", value.SourceID); err != nil {
-		return Document{}, err
+	if value == nil {
+		return nil, fmt.Errorf("document must be a JSON array")
 	}
-	if !digestPattern.MatchString(value.SourceDigest) {
-		return Document{}, fmt.Errorf("source_digest must be a sha256 digest")
-	}
-	if value.WindowUnits < 0 {
-		return Document{}, fmt.Errorf("window_units must not be negative")
-	}
-	if err := validateSelectedLanes(value.SelectedLanes); err != nil {
-		return Document{}, err
-	}
-	if value.Contexts == nil {
-		value.Contexts = make([]Context, 0)
-	}
-	selected := make(map[string]struct{}, len(value.SelectedLanes))
-	for _, laneID := range value.SelectedLanes {
-		selected[laneID] = struct{}{}
-	}
-	seenUnits := make(map[int]struct{})
-	for contextIndex := range value.Contexts {
-		context, err := canonicalizeContext(value.SourceID, selected, seenUnits, value.Contexts[contextIndex], contextIndex)
-		if err != nil {
-			return Document{}, err
-		}
-		value.Contexts[contextIndex] = context
-	}
-	return value, nil
-}
-
-func validateSelectedLanes(lanes []string) error {
-	if len(lanes) == 0 {
-		return fmt.Errorf("selected_lanes must not be empty")
-	}
-	for index, laneID := range lanes {
-		if err := requireIdentity(fmt.Sprintf("selected_lanes[%d]", index), laneID); err != nil {
-			return err
-		}
-		if index > 0 && lanes[index-1] >= laneID {
-			return fmt.Errorf("selected_lanes must be unique and in lexical order")
-		}
-	}
-	return nil
-}
-
-func canonicalizeContext(sourceID string, selected map[string]struct{}, seenUnits map[int]struct{}, value Context, contextIndex int) (Context, error) {
-	prefix := fmt.Sprintf("contexts[%d]", contextIndex)
-	if len(value.EvidenceRefs) == 0 {
-		return Context{}, fmt.Errorf("%s.evidence_refs must not be empty", prefix)
-	}
-	if len(value.Units) == 0 {
-		return Context{}, fmt.Errorf("%s.units must not be empty", prefix)
-	}
-	if err := validateRefIdentity(sourceID, value.ContextRef, prefix+".context_ref"); err != nil {
-		return Context{}, err
-	}
-	positions := make(map[int]int, len(value.Units))
-	for unitIndex := range value.Units {
-		unit := value.Units[unitIndex]
+	seenUnitIDs := make(map[int]struct{}, len(value))
+	sourceID := ""
+	for unitIndex := range value {
+		unit := value[unitIndex]
 		if unit.ID <= 0 || strings.TrimSpace(unit.Kind) == "" || strings.TrimSpace(unit.Text) == "" {
-			return Context{}, fmt.Errorf("%s.units[%d] has invalid required fields", prefix, unitIndex)
+			return nil, fmt.Errorf("units[%d] has invalid required fields", unitIndex)
 		}
-		if err := validateRefIdentity(sourceID, unit.Ref, fmt.Sprintf("%s.units[%d].ref", prefix, unitIndex)); err != nil {
-			return Context{}, err
+		if err := validateUnitRef(unit, unitIndex); err != nil {
+			return nil, err
 		}
-		if unit.Ref.StartUnitID != unit.ID || unit.Ref.EndUnitID != unit.ID {
-			return Context{}, fmt.Errorf("%s.units[%d].ref must identify unit id %d", prefix, unitIndex, unit.ID)
+		if sourceID == "" {
+			sourceID = unit.Ref.SourceID
+		} else if unit.Ref.SourceID != sourceID {
+			return nil, fmt.Errorf("units[%d].ref.source_id must match units[0].ref.source_id", unitIndex)
 		}
-		if _, exists := positions[unit.ID]; exists {
-			return Context{}, fmt.Errorf("%s.units contains duplicate unit id %d", prefix, unit.ID)
-		}
-		if _, exists := seenUnits[unit.ID]; exists {
-			return Context{}, fmt.Errorf("contexts contain duplicate unit id %d", unit.ID)
-		}
-		positions[unit.ID] = unitIndex
-		seenUnits[unit.ID] = struct{}{}
-	}
-	if value.ContextRef.StartUnitID != value.Units[0].ID || value.ContextRef.EndUnitID != value.Units[len(value.Units)-1].ID {
-		return Context{}, fmt.Errorf("%s.context_ref must identify the first and last units", prefix)
-	}
-	for evidenceIndex := range value.EvidenceRefs {
-		evidence := value.EvidenceRefs[evidenceIndex]
-		if _, ok := selected[evidence.LaneID]; !ok {
-			return Context{}, fmt.Errorf("%s.evidence_refs[%d].lane_id is not selected", prefix, evidenceIndex)
-		}
-		if err := requireIdentity(fmt.Sprintf("%s.evidence_refs[%d].lane_id", prefix, evidenceIndex), evidence.LaneID); err != nil {
-			return Context{}, err
-		}
-		if err := validateRefIdentity(sourceID, evidence.SourceRef, fmt.Sprintf("%s.evidence_refs[%d].source_ref", prefix, evidenceIndex)); err != nil {
-			return Context{}, err
-		}
-		start, startOK := positions[evidence.SourceRef.StartUnitID]
-		end, endOK := positions[evidence.SourceRef.EndUnitID]
-		if !startOK || !endOK || start > end {
-			return Context{}, fmt.Errorf("%s.evidence_refs[%d].source_ref is outside context units", prefix, evidenceIndex)
-		}
-		if evidenceIndex > 0 && !lessEvidenceRef(value.EvidenceRefs[evidenceIndex-1], evidence) {
-			return Context{}, fmt.Errorf("%s.evidence_refs must be unique and in deterministic order", prefix)
+		if _, exists := seenUnitIDs[unit.ID]; exists {
+			return nil, fmt.Errorf("units contains duplicate unit id %d", unit.ID)
 		}
+		seenUnitIDs[unit.ID] = struct{}{}
 	}
 	return value, nil
 }

-func validateRefIdentity(sourceID string, ref source.SourceRef, field string) error {
-	if ref.SourceID != sourceID {
-		return fmt.Errorf("%s.source_id does not match source_id", field)
+func validateUnitRef(unit source.SourceUnit, unitIndex int) error {
+	prefix := fmt.Sprintf("units[%d].ref", unitIndex)
+	if strings.TrimSpace(unit.Ref.SourceID) == "" || strings.TrimSpace(unit.Ref.SourceID) != unit.Ref.SourceID {
+		return fmt.Errorf("%s.source_id must be a non-empty trimmed string", prefix)
 	}
-	if ref.StartUnitID <= 0 || ref.EndUnitID <= 0 {
-		return fmt.Errorf("%s endpoints must be positive", field)
-	}
-	return nil
-}
-
-func requireIdentity(field, value string) error {
-	if strings.TrimSpace(value) == "" || strings.TrimSpace(value) != value {
-		return fmt.Errorf("%s must be a non-empty trimmed string", field)
+	if unit.Ref.StartUnitID != unit.ID || unit.Ref.EndUnitID != unit.ID {
+		return fmt.Errorf("%s must identify unit id %d", prefix, unit.ID)
 	}
 	return nil
 }

 func clone(value Document) (Document, error) {
-	value.SelectedLanes = append([]string(nil), value.SelectedLanes...)
-	if value.Contexts == nil {
-		value.Contexts = make([]Context, 0)
-	} else {
-		contexts := make([]Context, len(value.Contexts))
-		for contextIndex, context := range value.Contexts {
-			contexts[contextIndex].ContextRef = context.ContextRef
-			contexts[contextIndex].EvidenceRefs = append([]EvidenceRef(nil), context.EvidenceRefs...)
-			contexts[contextIndex].Units = make([]source.SourceUnit, len(context.Units))
-			for unitIndex, unit := range context.Units {
-				cloned, err := cloneSourceUnit(unit)
-				if err != nil {
-					return Document{}, fmt.Errorf("clone contexts[%d].units[%d]: %w", contextIndex, unitIndex, err)
-				}
-				contexts[contextIndex].Units[unitIndex] = cloned
-			}
-		}
-		value.Contexts = contexts
+	if value == nil {
+		return nil, nil
 	}
-	return value, nil
+	cloned := make(Document, len(value))
+	for unitIndex, unit := range value {
+		owned, err := cloneSourceUnit(unit)
+		if err != nil {
+			return nil, fmt.Errorf("clone units[%d]: %w", unitIndex, err)
+		}
+		cloned[unitIndex] = owned
+	}
+	return cloned, nil
 }

 func cloneSourceUnit(unit source.SourceUnit) (source.SourceUnit, error) {
--- a/internal/framework/evidencecontext/evidencecontext_test.go
+++ b/internal/framework/evidencecontext/evidencecontext_test.go
@@ -2,7 +2,6 @@ package evidencecontext

 import (
 	"bytes"
-	"encoding/json"
 	"math"
 	"os"
 	"reflect"
@@ -12,126 +11,57 @@ import (
 	"gitea.maximumdirect.net/eric/notarius/internal/core/source"
 )

-func TestBuildExpandsAndMergesEvidenceByDocumentPosition(t *testing.T) {
+func TestBuildSelectsExpandedSourceUnitUnion(t *testing.T) {
 	for _, test := range []struct {
-		name      string
-		window    int
-		evidence  []LaneEvidence
-		wantUnits [][]int
-		wantRefs  [][]EvidenceRef
+		name    string
+		window  int
+		refs    []source.SourceRef
+		wantIDs []int
 	}{
-		{
-			name:      "zero window",
-			evidence:  []LaneEvidence{{LaneID: "npcs", SourceRefs: []source.SourceRef{ref(3, 3)}}},
-			wantUnits: [][]int{{3}},
-			wantRefs:  [][]EvidenceRef{{{LaneID: "npcs", SourceRef: ref(3, 3)}}},
-		},
-		{
-			name:      "non monotonic ids use positions and clip boundaries",
-			window:    1,
-			evidence:  []LaneEvidence{{LaneID: "npcs", SourceRefs: []source.SourceRef{ref(3, 3)}}},
-			wantUnits: [][]int{{10, 3, 30}},
-			wantRefs:  [][]EvidenceRef{{{LaneID: "npcs", SourceRef: ref(3, 3)}}},
-		},
-		{
-			name:      "separate gaps stay separate",
-			evidence:  []LaneEvidence{{LaneID: "npcs", SourceRefs: []source.SourceRef{ref(10, 10), ref(50, 50)}}},
-			wantUnits: [][]int{{10}, {50}},
-			wantRefs:  [][]EvidenceRef{{{LaneID: "npcs", SourceRef: ref(10, 10)}}, {{LaneID: "npcs", SourceRef: ref(50, 50)}}},
-		},
-		{
-			name:      "overlapping windows merge",
-			window:    1,
-			evidence:  []LaneEvidence{{LaneID: "npcs", SourceRefs: []source.SourceRef{ref(3, 3), ref(30, 30)}}},
-			wantUnits: [][]int{{10, 3, 30, 7}},
-			wantRefs:  [][]EvidenceRef{{{LaneID: "npcs", SourceRef: ref(3, 3)}, {LaneID: "npcs", SourceRef: ref(30, 30)}}},
-		},
-		{
-			name:      "contiguous windows merge",
-			window:    1,
-			evidence:  []LaneEvidence{{LaneID: "npcs", SourceRefs: []source.SourceRef{ref(10, 10), ref(7, 7)}}},
-			wantUnits: [][]int{{10, 3, 30, 7, 50}},
-			wantRefs:  [][]EvidenceRef{{{LaneID: "npcs", SourceRef: ref(7, 7)}, {LaneID: "npcs", SourceRef: ref(10, 10)}}},
-		},
-		{
-			name: "duplicate contributions retain unique lane attribution",
-			evidence: []LaneEvidence{
-				{LaneID: "spells", SourceRefs: []source.SourceRef{ref(30, 30), ref(30, 30)}},
-				{LaneID: "npcs", SourceRefs: []source.SourceRef{ref(30, 30)}},
-			},
-			wantUnits: [][]int{{30}},
-			wantRefs:  [][]EvidenceRef{{{LaneID: "npcs", SourceRef: ref(30, 30)}, {LaneID: "spells", SourceRef: ref(30, 30)}}},
-		},
-		{
-			name:      "empty contributions retain explicit empty contexts",
-			evidence:  []LaneEvidence{{LaneID: "npcs"}},
-			wantUnits: [][]int{},
-			wantRefs:  [][]EvidenceRef{},
-		},
-		{
-			name:      "largest window clips without overflow",
-			window:    math.MaxInt,
-			evidence:  []LaneEvidence{{LaneID: "npcs", SourceRefs: []source.SourceRef{ref(30, 30)}}},
-			wantUnits: [][]int{{10, 3, 30, 7, 50}},
-			wantRefs:  [][]EvidenceRef{{{LaneID: "npcs", SourceRef: ref(30, 30)}}},
-		},
+		{name: "zero window", refs: []source.SourceRef{ref(3, 3)}, wantIDs: []int{3}},
+		{name: "multi unit citation includes complete range", refs: []source.SourceRef{ref(3, 7)}, wantIDs: []int{3, 30, 7}},
+		{name: "non monotonic IDs use document positions", window: 1, refs: []source.SourceRef{ref(3, 3)}, wantIDs: []int{10, 3, 30}},
+		{name: "boundary clamping", window: 1, refs: []source.SourceRef{ref(10, 10), ref(50, 50)}, wantIDs: []int{10, 3, 7, 50}},
+		{name: "overlapping and adjacent windows merge", window: 1, refs: []source.SourceRef{ref(3, 3), ref(30, 30), ref(30, 30)}, wantIDs: []int{10, 3, 30, 7}},
+		{name: "adjacent expanded ranges merge", window: 1, refs: []source.SourceRef{ref(10, 10), ref(7, 7)}, wantIDs: []int{10, 3, 30, 7, 50}},
+		{name: "largest window clips without overflow", window: math.MaxInt, refs: []source.SourceRef{ref(30, 30)}, wantIDs: []int{10, 3, 30, 7, 50}},
+		{name: "no references returns an initialized empty document", wantIDs: []int{}},
 	} {
 		t.Run(test.name, func(t *testing.T) {
-			document := testDocument(t)
-			got, err := Build(BuildRequest{Source: document, WindowUnits: test.window, SelectedLanes: []string{"spells", "npcs"}, LaneEvidence: test.evidence})
+			got, err := Build(BuildRequest{Source: testDocument(t), WindowUnits: test.window, SourceRefs: test.refs})
 			if err != nil {
 				t.Fatalf("Build() error = %v", err)
 			}
-			if want := []string{"npcs", "spells"}; !reflect.DeepEqual(got.SelectedLanes, want) {
-				t.Fatalf("SelectedLanes = %#v, want %#v", got.SelectedLanes, want)
+			if got == nil {
+				t.Fatal("Build() returned a nil document")
 			}
-			if got.WindowUnits != test.window || got.SourceID != document.ID || got.SourceDigest != document.Digest {
-				t.Fatalf("Build() identity = %#v, want source and window identity", got)
-			}
-			if actual := contextUnitIDs(got.Contexts); !reflect.DeepEqual(actual, test.wantUnits) {
-				t.Fatalf("context unit ids = %#v, want %#v", actual, test.wantUnits)
-			}
-			if actual := contextEvidenceRefs(got.Contexts); !reflect.DeepEqual(actual, test.wantRefs) {
-				t.Fatalf("context evidence refs = %#v, want %#v", actual, test.wantRefs)
+			if actual := unitIDs(got); !reflect.DeepEqual(actual, test.wantIDs) {
+				t.Fatalf("unit IDs = %#v, want %#v", actual, test.wantIDs)
 			}
 		})
 	}
 }

-func TestBuildIsStableAndOwnsSourceAndInputs(t *testing.T) {
+func TestBuildCopiesSelectedUnitsAndMetadata(t *testing.T) {
 	document := testDocument(t)
-	refs := []source.SourceRef{ref(30, 30), ref(3, 3)}
-	request := BuildRequest{
-		Source:        document,
-		WindowUnits:   1,
-		SelectedLanes: []string{"spells", "npcs"},
-		LaneEvidence:  []LaneEvidence{{LaneID: "spells", SourceRefs: refs}, {LaneID: "npcs", SourceRefs: []source.SourceRef{ref(3, 3)}}},
-	}
-	first, err := Build(request)
+	first, err := Build(BuildRequest{Source: document, WindowUnits: 1, SourceRefs: []source.SourceRef{ref(3, 3)}})
 	if err != nil {
 		t.Fatal(err)
 	}
-	secondRequest := request
-	secondRequest.LaneEvidence = []LaneEvidence{{LaneID: "npcs", SourceRefs: []source.SourceRef{ref(3, 3)}}, {LaneID: "spells", SourceRefs: []source.SourceRef{ref(3, 3), ref(30, 30)}}}
-	second, err := Build(secondRequest)
+	second, err := Build(BuildRequest{Source: document, WindowUnits: 1, SourceRefs: []source.SourceRef{ref(3, 3)}})
 	if err != nil {
 		t.Fatal(err)
 	}
-	if !reflect.DeepEqual(first, second) {
-		t.Fatalf("Build() order differs:\nfirst: %#v\nsecond: %#v", first, second)
+	if !reflect.DeepEqual(first[0], document.Units[0]) {
+		t.Fatalf("first unit = %#v, want unchanged source unit %#v", first[0], document.Units[0])
 	}
-	first.SelectedLanes[0] = "changed"
-	first.Contexts[0].Units[0].Metadata["nested"].(map[string]any)["value"] = "changed"
+	first[0].Metadata["nested"].(map[string]any)["value"] = "changed"
 	if document.Units[0].Metadata["nested"].(map[string]any)["value"] != "original" {
-		t.Fatal("Build() returned metadata aliases to source document")
+		t.Fatal("Build() returned metadata aliases to the source document")
 	}
 	document.Units[0].Metadata["nested"].(map[string]any)["value"] = "later"
-	if second.Contexts[0].Units[0].Metadata["nested"].(map[string]any)["value"] != "original" {
-		t.Fatal("Build() retained metadata aliases to source document")
-	}
-	refs[0].StartUnitID = 999
-	if !containsEvidenceRef(second.Contexts[0].EvidenceRefs, ref(30, 30)) {
-		t.Fatal("Build() retained source-reference input aliases")
+	if second[0].Metadata["nested"].(map[string]any)["value"] != "original" {
+		t.Fatal("Build() retained metadata aliases to the source document")
 	}
 }

@@ -142,18 +72,11 @@ func TestBuildRejectsInvalidInputs(t *testing.T) {
 		want   string
 	}{
 		{name: "negative window", mutate: func(request *BuildRequest) { request.WindowUnits = -1 }, want: "window_units"},
-		{name: "blank selected lane", mutate: func(request *BuildRequest) { request.SelectedLanes = []string{" "} }, want: "selected_lanes"},
-		{name: "duplicate selected lane", mutate: func(request *BuildRequest) { request.SelectedLanes = []string{"npcs", " npcs "} }, want: "duplicated"},
-		{name: "unselected contribution", mutate: func(request *BuildRequest) {
-			request.LaneEvidence = []LaneEvidence{{LaneID: "other", SourceRefs: []source.SourceRef{ref(3, 3)}}}
-		}, want: "not selected"},
 		{name: "source digest mismatch", mutate: func(request *BuildRequest) { request.Source.Digest = "sha256:" + strings.Repeat("0", 64) }, want: "does not match"},
-		{name: "invalid reference", mutate: func(request *BuildRequest) {
-			request.LaneEvidence = []LaneEvidence{{LaneID: "npcs", SourceRefs: []source.SourceRef{ref(99, 99)}}}
-		}, want: "source reference[0]"},
+		{name: "invalid reference", mutate: func(request *BuildRequest) { request.SourceRefs = []source.SourceRef{ref(99, 99)} }, want: "source reference[0]"},
 	} {
 		t.Run(test.name, func(t *testing.T) {
-			request := BuildRequest{Source: testDocument(t), SelectedLanes: []string{"npcs"}, LaneEvidence: []LaneEvidence{{LaneID: "npcs", SourceRefs: []source.SourceRef{ref(3, 3)}}}}
+			request := BuildRequest{Source: testDocument(t), SourceRefs: []source.SourceRef{ref(3, 3)}}
 			test.mutate(&request)
 			if _, err := Build(request); err == nil || !strings.Contains(err.Error(), test.want) {
 				t.Fatalf("Build() error = %v, want %q", err, test.want)
@@ -162,7 +85,7 @@ func TestBuildRejectsInvalidInputs(t *testing.T) {
 	}
 }

-func TestCodecRoundTripsCompactFixtureAndOwnsDecodedValues(t *testing.T) {
+func TestCodecRoundTripsFixtureAndOwnsValues(t *testing.T) {
 	fixture, err := os.ReadFile("testdata/source_evidence_context.v1.json")
 	if err != nil {
 		t.Fatal(err)
@@ -179,15 +102,16 @@ func TestCodecRoundTripsCompactFixtureAndOwnsDecodedValues(t *testing.T) {
 	if !bytes.Equal(encoded, bytes.TrimSpace(fixture)) {
 		t.Fatalf("fixture does not use canonical encoding\nwant: %s\n got: %s", fixture, encoded)
 	}
-	value.Contexts[0].Units[0].Text = "changed"
+	value[0].Text = "changed"
 	decoded, err := codec.Decode(encoded)
 	if err != nil {
 		t.Fatal(err)
 	}
-	if decoded.Contexts[0].Units[0].Text != "The party meets Rowan." {
+	if decoded[0].Text != "The party meets Rowan." {
 		t.Fatal("Encode() retained mutable document storage")
 	}
-	built, err := Build(BuildRequest{Source: testDocument(t), WindowUnits: 1, SelectedLanes: []string{"npcs"}, LaneEvidence: []LaneEvidence{{LaneID: "npcs", SourceRefs: []source.SourceRef{ref(3, 3)}}}})
+
+	built, err := Build(BuildRequest{Source: testDocument(t), WindowUnits: 1, SourceRefs: []source.SourceRef{ref(3, 3)}})
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -203,82 +127,52 @@ func TestCodecRoundTripsCompactFixtureAndOwnsDecodedValues(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	first.Contexts[0].Units[0].Metadata["nested"].(map[string]any)["value"] = "changed"
-	if second.Contexts[0].Units[0].Metadata["nested"].(map[string]any)["value"] != "original" {
+	first[0].Metadata["nested"].(map[string]any)["value"] = "changed"
+	if second[0].Metadata["nested"].(map[string]any)["value"] != "original" {
 		t.Fatal("Decode() returned metadata aliases")
 	}
 }

-func TestCodecRejectsInvalidDurableBoundaries(t *testing.T) {
-	value, err := Build(BuildRequest{Source: testDocument(t), SelectedLanes: []string{"npcs"}, LaneEvidence: []LaneEvidence{{LaneID: "npcs", SourceRefs: []source.SourceRef{ref(3, 3)}}}})
-	if err != nil {
-		t.Fatal(err)
-	}
+func TestCodecRejectsInvalidDurablePayloads(t *testing.T) {
 	for _, test := range []struct {
-		name   string
-		mutate func(*Document)
+		name    string
+		content string
 	}{
-		{name: "unsorted lanes", mutate: func(value *Document) { value.SelectedLanes = []string{"z", "a"} }},
-		{name: "context range mismatch", mutate: func(value *Document) { value.Contexts[0].ContextRef.EndUnitID = 999 }},
-		{name: "mismatched evidence source", mutate: func(value *Document) { value.Contexts[0].EvidenceRefs[0].SourceRef.SourceID = "other" }},
-		{name: "invalid evidence range", mutate: func(value *Document) {
-			value.Contexts[0].EvidenceRefs[0].SourceRef.StartUnitID = 10
-		}},
-		{name: "duplicate context unit", mutate: func(value *Document) { value.Contexts = append(value.Contexts, value.Contexts[0]) }},
+		{name: "null", content: "null"},
+		{name: "wrapper object", content: `{"units":[]}`},
+		{name: "missing required unit field", content: `[{"id":1,"kind":"segment","ref":{"source_id":"session","start_unit_id":1,"end_unit_id":1}}]`},
+		{name: "unknown unit field", content: `[{"id":1,"kind":"segment","text":"text","ref":{"source_id":"session","start_unit_id":1,"end_unit_id":1},"unknown":true}]`},
+		{name: "unknown reference field", content: `[{"id":1,"kind":"segment","text":"text","ref":{"source_id":"session","start_unit_id":1,"end_unit_id":1,"unknown":true}}]`},
+		{name: "invalid self reference", content: `[{"id":1,"kind":"segment","text":"text","ref":{"source_id":"session","start_unit_id":1,"end_unit_id":2}}]`},
+		{name: "mixed source documents", content: `[{"id":1,"kind":"segment","text":"one","ref":{"source_id":"session-one","start_unit_id":1,"end_unit_id":1}},{"id":2,"kind":"segment","text":"two","ref":{"source_id":"session-two","start_unit_id":2,"end_unit_id":2}}]`},
+		{name: "duplicate units", content: `[{"id":1,"kind":"segment","text":"one","ref":{"source_id":"session","start_unit_id":1,"end_unit_id":1}},{"id":1,"kind":"segment","text":"two","ref":{"source_id":"session","start_unit_id":1,"end_unit_id":1}}]`},
+		{name: "multiple JSON values", content: `[] []`},
 	} {
 		t.Run(test.name, func(t *testing.T) {
-			candidate, err := clone(value)
-			if err != nil {
-				t.Fatal(err)
-			}
-			test.mutate(&candidate)
-			if _, err := New().Encode(candidate); err == nil {
-				t.Fatal("Encode() error = nil, want durable model rejection")
-			}
-		})
-	}
-	content, err := New().Encode(value)
-	if err != nil {
-		t.Fatal(err)
-	}
-	for _, test := range []struct {
-		name   string
-		mutate func(map[string]any)
-	}{
-		{name: "missing contexts", mutate: func(value map[string]any) { delete(value, "contexts") }},
-		{name: "null contexts", mutate: func(value map[string]any) { value["contexts"] = nil }},
-		{name: "unknown fixed field", mutate: func(value map[string]any) { value["unknown"] = true }},
-		{name: "missing units", mutate: func(value map[string]any) { delete(contextObject(value, 0), "units") }},
-		{name: "null evidence refs", mutate: func(value map[string]any) { contextObject(value, 0)["evidence_refs"] = nil }},
-	} {
-		t.Run(test.name, func(t *testing.T) {
-			raw := decodeJSON(t, content)
-			test.mutate(raw)
-			mutated, err := json.Marshal(raw)
-			if err != nil {
-				t.Fatal(err)
-			}
-			if _, err := New().Decode(mutated); err == nil {
+			if _, err := New().Decode([]byte(test.content)); err == nil {
 				t.Fatal("Decode() error = nil, want strict payload rejection")
 			}
 		})
 	}
-	if _, err := New().Decode(append(content, []byte(" {}")...)); err == nil {
-		t.Fatal("Decode() error = nil, want trailing JSON rejection")
+	if _, err := New().Encode(nil); err == nil {
+		t.Fatal("Encode(nil) error = nil, want array rejection")
 	}
 }

-func TestSerializeUsesFixedArtifactIdentity(t *testing.T) {
-	artifact, err := Serialize(BuildRequest{Source: testDocument(t), SelectedLanes: []string{"npcs"}})
+func TestSerializeUsesFixedArtifactIdentityAndEmptyArray(t *testing.T) {
+	artifact, err := Serialize(BuildRequest{Source: testDocument(t)})
 	if err != nil {
 		t.Fatal(err)
 	}
 	if artifact.Kind != ArtifactKind || artifact.MediaType != MediaType || artifact.Schema.ID != SchemaID || artifact.Schema.Name != SchemaName || artifact.Schema.Version != SchemaVersion {
 		t.Fatalf("Serialize() = %#v, want fixed artifact identity", artifact)
 	}
+	if string(artifact.Content) != "[]" {
+		t.Fatalf("Serialize() content = %s, want []", artifact.Content)
+	}
 	decoded, err := New().Decode(artifact.Content)
-	if err != nil || len(decoded.Contexts) != 0 || decoded.Contexts == nil {
-		t.Fatalf("Decode(Serialize()) = %#v, %v; want explicit empty contexts", decoded, err)
+	if err != nil || decoded == nil || len(decoded) != 0 {
+		t.Fatalf("Decode(Serialize()) = %#v, %v; want explicit empty array", decoded, err)
 	}
 }

@@ -306,45 +200,10 @@ func ref(start, end int) source.SourceRef {
 	return source.SourceRef{SourceID: "session", StartUnitID: start, EndUnitID: end}
 }

-func contextUnitIDs(contexts []Context) [][]int {
-	values := make([][]int, len(contexts))
-	for index, context := range contexts {
-		values[index] = make([]int, len(context.Units))
-		for unitIndex, unit := range context.Units {
-			values[index][unitIndex] = unit.ID
-		}
+func unitIDs(units Document) []int {
+	values := make([]int, len(units))
+	for index, unit := range units {
+		values[index] = unit.ID
 	}
 	return values
 }
-
-func contextEvidenceRefs(contexts []Context) [][]EvidenceRef {
-	values := make([][]EvidenceRef, len(contexts))
-	for index, context := range contexts {
-		values[index] = append([]EvidenceRef(nil), context.EvidenceRefs...)
-	}
-	return values
-}
-
-func containsEvidenceRef(values []EvidenceRef, want source.SourceRef) bool {
-	for _, value := range values {
-		if value.SourceRef == want {
-			return true
-		}
-	}
-	return false
-}
-
-func decodeJSON(t *testing.T, content []byte) map[string]any {
-	t.Helper()
-	decoder := json.NewDecoder(bytes.NewReader(content))
-	decoder.UseNumber()
-	var value map[string]any
-	if err := decoder.Decode(&value); err != nil {
-		t.Fatal(err)
-	}
-	return value
-}
-
-func contextObject(value map[string]any, index int) map[string]any {
-	return value["contexts"].([]any)[index].(map[string]any)
-}
--- a/internal/framework/evidencecontext/model.go
+++ b/internal/framework/evidencecontext/model.go
@@ -14,37 +14,12 @@ const (
 	MediaType                            = "application/json"
 )

-// Document is the durable union of direct evidence and surrounding source
-// context selected for one accepted source document.
-type Document struct {
-	SourceID      string    `json:"source_id"`
-	SourceDigest  string    `json:"source_digest"`
-	WindowUnits   int       `json:"window_units"`
-	SelectedLanes []string  `json:"selected_lanes"`
-	Contexts      []Context `json:"contexts"`
-}
+// Document is the durable selected source-unit excerpt.
+type Document []source.SourceUnit

-type Context struct {
-	ContextRef   source.SourceRef    `json:"context_ref"`
-	EvidenceRefs []EvidenceRef       `json:"evidence_refs"`
-	Units        []source.SourceUnit `json:"units"`
-}
-
-type EvidenceRef struct {
-	LaneID    string           `json:"lane_id"`
-	SourceRef source.SourceRef `json:"source_ref"`
-}
-
-// LaneEvidence attributes direct source references to one selected lane.
-type LaneEvidence struct {
-	LaneID     string             `json:"lane_id"`
-	SourceRefs []source.SourceRef `json:"source_refs"`
-}
-
-// BuildRequest supplies accepted source material and direct lane evidence.
+// BuildRequest supplies accepted source material and projected source references.
 type BuildRequest struct {
-	Source        *source.SourceDocument
-	WindowUnits   int
-	SelectedLanes []string
-	LaneEvidence  []LaneEvidence
+	Source      *source.SourceDocument
+	WindowUnits int
+	SourceRefs  []source.SourceRef
 }
--- a/internal/framework/evidencecontext/testdata/source_evidence_context.v1.json
+++ b/internal/framework/evidencecontext/testdata/source_evidence_context.v1.json
@@ -1 +1 @@
-{"source_id":"session-alpha","source_digest":"sha256:0000000000000000000000000000000000000000000000000000000000000000","window_units":0,"selected_lanes":["npcs"],"contexts":[{"context_ref":{"source_id":"session-alpha","start_unit_id":13,"end_unit_id":13},"evidence_refs":[{"lane_id":"npcs","source_ref":{"source_id":"session-alpha","start_unit_id":13,"end_unit_id":13}}],"units":[{"id":13,"kind":"transcript_segment","text":"The party meets Rowan.","ref":{"source_id":"session-alpha","start_unit_id":13,"end_unit_id":13}}]}]}
+[{"id":13,"kind":"transcript_segment","text":"The party meets Rowan.","ref":{"source_id":"session-alpha","start_unit_id":13,"end_unit_id":13}}]
--- a/internal/framework/pipeline/evidence_output.go
+++ b/internal/framework/pipeline/evidence_output.go
@@ -20,7 +20,6 @@ type debugEvidenceContextSummary struct {
 	SchemaVersion string                 `json:"schema_version"`
 	SelectedLanes []string               `json:"selected_lanes"`
 	WindowUnits   int                    `json:"window_units"`
-	ContextCount  int                    `json:"context_count"`
 	UnitCount     int                    `json:"unit_count"`
 	SourceDigest  string                 `json:"source_digest"`
 }
@@ -49,10 +48,9 @@ func buildOutputEvidenceContext(prepared *PreparedPipeline, doc *source.SourceDo
 	}

 	request := evidencecontext.BuildRequest{
-		Source:        doc,
-		WindowUnits:   prepared.evidencePlan.policy.WindowUnits,
-		SelectedLanes: append([]string(nil), prepared.evidencePlan.policy.LaneIDs...),
-		LaneEvidence:  make([]evidencecontext.LaneEvidence, 0, len(prepared.evidencePlan.lanes)),
+		Source:      doc,
+		WindowUnits: prepared.evidencePlan.policy.WindowUnits,
+		SourceRefs:  make([]source.SourceRef, 0),
 	}
 	for _, lane := range prepared.evidencePlan.lanes {
 		output, ok := byLane[lane.laneID]
@@ -73,10 +71,7 @@ func buildOutputEvidenceContext(prepared *PreparedPipeline, doc *source.SourceDo
 		if err != nil {
 			return nil, nil, fmt.Errorf("evidence context output lane %q: accepted normalized artifact cannot be projected", lane.laneID)
 		}
-		request.LaneEvidence = append(request.LaneEvidence, evidencecontext.LaneEvidence{
-			LaneID:     lane.laneID,
-			SourceRefs: append([]source.SourceRef(nil), references...),
-		})
+		request.SourceRefs = append(request.SourceRefs, references...)
 	}

 	document, err := evidencecontext.Build(request)
@@ -99,13 +94,10 @@ func buildOutputEvidenceContext(prepared *PreparedPipeline, doc *source.SourceDo
 		SchemaID:      artifact.Schema.ID,
 		SchemaName:    artifact.Schema.Name,
 		SchemaVersion: artifact.Schema.Version,
-		SelectedLanes: append([]string(nil), document.SelectedLanes...),
-		WindowUnits:   document.WindowUnits,
-		ContextCount:  len(document.Contexts),
-		SourceDigest:  document.SourceDigest,
-	}
-	for _, context := range document.Contexts {
-		summary.UnitCount += len(context.Units)
+		SelectedLanes: append([]string(nil), prepared.evidencePlan.policy.LaneIDs...),
+		WindowUnits:   prepared.evidencePlan.policy.WindowUnits,
+		SourceDigest:  doc.Digest,
+		UnitCount:     len(document),
 	}
 	return contracts.CloneSerializedArtifactPointer(artifact), &summary, nil
 }
--- a/internal/framework/pipeline/evidence_output_test.go
+++ b/internal/framework/pipeline/evidence_output_test.go
@@ -97,14 +97,11 @@ func TestRunnerBuildsEvidenceContextFromSelectedNormalizedOutputs(t *testing.T)
 	}

 	value := decodeCapturedEvidence(t, encoder)
-	if !reflect.DeepEqual(value.SelectedLanes, []string{"alpha", "beta", "inactive"}) || len(value.Contexts) != 1 || len(value.Contexts[0].Units) != 3 {
+	if actual := []int{value[0].ID, value[1].ID, value[2].ID}; !reflect.DeepEqual(actual, []int{1, 2, 3}) {
 		t.Fatalf("evidence context = %#v, want selected union", value)
 	}
-	if got := value.Contexts[0].EvidenceRefs; len(got) != 2 || got[0].LaneID != "alpha" || got[1].LaneID != "beta" {
-		t.Fatalf("evidence refs = %#v, want both selected lanes", got)
-	}
 	debugJSON := string(debug.json["output/evidence-context.json"])
-	if strings.Contains(debugJSON, "text-1") || strings.Contains(debugJSON, "metadata") || !strings.Contains(debugJSON, `"artifact_kind":"source/evidence-context"`) || !strings.Contains(debugJSON, `"schema_id":"notarius.source.evidence_context"`) || !strings.Contains(debugJSON, `"context_count":1`) || !strings.Contains(debugJSON, `"unit_count":3`) {
+	if strings.Contains(debugJSON, "text-1") || strings.Contains(debugJSON, "metadata") || !strings.Contains(debugJSON, `"artifact_kind":"source/evidence-context"`) || !strings.Contains(debugJSON, `"schema_id":"notarius.source.evidence_context"`) || strings.Contains(debugJSON, "context_count") || !strings.Contains(debugJSON, `"unit_count":3`) {
 		t.Fatalf("evidence debug envelope = %s, want only allowlisted summary", debugJSON)
 	}
 }
@@ -134,7 +131,7 @@ func TestRunnerEvidenceContextOmitsAbsentAndRejectedLanes(t *testing.T) {
 		t.Fatalf("rejections = %#v, want rejected lane unchanged", result.Rejected)
 	}
 	value := decodeCapturedEvidence(t, encoder)
-	if len(value.Contexts) != 1 || len(value.Contexts[0].EvidenceRefs) != 1 || value.Contexts[0].EvidenceRefs[0].LaneID != "present" {
+	if len(value) != 1 || value[0].ID != 1 {
 		t.Fatalf("evidence context = %#v, want present lane only", value)
 	}
 }
@@ -232,7 +229,7 @@ func TestRunnerEvidenceContextRebuildsFromAcceptedCheckpoint(t *testing.T) {
 		t.Fatalf("Run() error = %v", err)
 	}
 	value := decodeCapturedEvidence(t, encoder)
-	if len(value.Contexts) != 1 || value.Contexts[0].EvidenceRefs[0].LaneID != "notes" {
+	if len(value) != 1 || value[0].ID != 1 {
 		t.Fatalf("evidence context = %#v, want checkpointed normalized output", value)
 	}
 }
--- a/internal/modules/generic/output/json/encoder_test.go
+++ b/internal/modules/generic/output/json/encoder_test.go
@@ -353,8 +353,8 @@ func TestEncodeIncludesValidatedEvidenceContext(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Decode(evidence context file) error = %v", err)
 	}
-	if len(value.Contexts) != 0 {
-		t.Fatalf("evidence context = %#v, want explicit empty contexts", value)
+	if len(value) != 1 || value[0].ID != 7 || value[0].Text != "Source content retained only in the evidence artifact." {
+		t.Fatalf("evidence context = %#v, want the published source-unit array", value)
 	}
 	index := decodeObject(t, fileBytes(t, result.Files, "index.json"))
 	if got, want := index["evidence_context"], map[string]any{
@@ -786,7 +786,8 @@ func acceptedEvidenceContextArtifact(t *testing.T) contracts.SerializedArtifact
 	}
 	document.Digest = digest
 	artifact, err := evidencecontext.Serialize(evidencecontext.BuildRequest{
-		Source: document, WindowUnits: 3, SelectedLanes: []string{"spells"},
+		Source: document, WindowUnits: 3,
+		SourceRefs: []source.SourceRef{{SourceID: "source-1", StartUnitID: 7, EndUnitID: 7}},
 	})
 	if err != nil {
 		t.Fatal(err)
--- a/internal/modules/integration/dnd_location_registry_runner_test.go
+++ b/internal/modules/integration/dnd_location_registry_runner_test.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"reflect"
 	"strings"
 	"sync"
 	"testing"
@@ -71,20 +72,17 @@ func TestLocationRegistryHandoffProducesOccurrencesAndEvidence(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Decode(evidence context) error = %v", err)
 	}
-	if !locationEvidenceHasLane(evidence, "locations") || !locationEvidenceHasLane(evidence, "occurrences") {
-		t.Fatalf("evidence context = %#v, want registry and occurrence evidence from their own artifacts", evidence)
+	if actual := locationEvidenceUnitIDs(evidence); !reflect.DeepEqual(actual, []int{1, 2, 3, 4, 5}) {
+		t.Fatalf("evidence context = %#v, want deduplicated registry and occurrence source-unit evidence", evidence)
 	}
 }

-func locationEvidenceHasLane(document evidencecontext.Document, laneID string) bool {
-	for _, context := range document.Contexts {
-		for _, reference := range context.EvidenceRefs {
-			if reference.LaneID == laneID {
-				return true
-			}
-		}
+func locationEvidenceUnitIDs(document evidencecontext.Document) []int {
+	ids := make([]int, len(document))
+	for index, unit := range document {
+		ids[index] = unit.ID
 	}
-	return false
+	return ids
 }

 func TestLocationOccurrenceConsumerDoesNotRunAfterRejectedRegistry(t *testing.T) {
--- a/internal/modules/integration/dnd_npc_grounded_test.go
+++ b/internal/modules/integration/dnd_npc_grounded_test.go
@@ -279,22 +279,8 @@ func TestProductionDNDOutputPublishesSelectedEvidenceContext(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Decode(evidence context) error = %v", err)
 	}
-	if !reflect.DeepEqual(value.SelectedLanes, []string{"combat", "npc_registry", "spells"}) {
-		t.Fatalf("selected lanes = %#v, want configured production lanes without scene descriptions", value.SelectedLanes)
-	}
-	if len(value.Contexts) != 2 || len(value.Contexts[0].Units) != 1 || len(value.Contexts[1].Units) != 1 || value.Contexts[0].Units[0].ID != 10 || value.Contexts[1].Units[0].ID != 20 {
-		t.Fatalf("evidence contexts = %#v, want source-position union with non-monotonic unit IDs", value.Contexts)
-	}
-	firstRefs := value.Contexts[0].EvidenceRefs
-	if len(firstRefs) != 3 || firstRefs[0].LaneID != "combat" || firstRefs[1].LaneID != "npc_registry" || firstRefs[2].LaneID != "spells" {
-		t.Fatalf("first context evidence = %#v, want overlapping selected lane references", firstRefs)
-	}
-	for _, context := range value.Contexts {
-		for _, reference := range context.EvidenceRefs {
-			if reference.LaneID == "scene-descriptions" {
-				t.Fatalf("evidence refs = %#v, want scene descriptions excluded by allowlist", value.Contexts)
-			}
-		}
+	if actual := evidenceUnitIDs(value); !reflect.DeepEqual(actual, []int{10, 20}) {
+		t.Fatalf("evidence units = %#v, want deduplicated source-position union without scene descriptions", actual)
 	}
 }

@@ -312,11 +298,19 @@ func TestProductionDNDOutputCanExplicitlySelectSceneDescriptionEvidence(t *testi
 	if err != nil {
 		t.Fatalf("Decode(evidence context) error = %v", err)
 	}
-	if !reflect.DeepEqual(value.SelectedLanes, []string{"scene-descriptions"}) || len(value.Contexts) == 0 || len(value.Contexts[0].EvidenceRefs) == 0 || value.Contexts[0].EvidenceRefs[0].LaneID != "scene-descriptions" {
-		t.Fatalf("evidence context = %#v, want explicitly selected scene-description evidence", value)
+	if len(value) == 0 {
+		t.Fatalf("evidence context = %#v, want explicitly selected scene-description source units", value)
 	}
 }

+func evidenceUnitIDs(value evidencecontext.Document) []int {
+	ids := make([]int, len(value))
+	for index, unit := range value {
+		ids[index] = unit.ID
+	}
+	return ids
+}
+
 func TestGroundedPipelineSkipsCombatForExactNarrativeScene(t *testing.T) {
 	registries := productionNPCRegistries(t)
 	configValue := loadGroundedPipelineConfig(t)
Author	SHA1	Message	Date
Eric Rakestraw	bef8ca263b	Tighten evidence context source excerpts	2026-08-09 20:04:46 +00:00
Eric Rakestraw	f6d037b613	Document evidence context source unit excerpts	2026-08-09 19:47:27 +00:00
Eric Rakestraw	449b506804	Update evidence context output coverage	2026-08-09 19:45:21 +00:00
Eric Rakestraw	071a78ae22	Replace evidence context with source unit excerpts	2026-08-09 19:42:33 +00:00