diff --git a/src/main/tape/application/common.ts b/src/main/tape/application/common.ts
index 5f2fa5d24..898bab5ef 100644
--- a/src/main/tape/application/common.ts
+++ b/src/main/tape/application/common.ts
@@ -1,6 +1,5 @@
 import { TAPE_INCARNATION_META_KEY, type DeepChatTapeEntryRow } from '../domain/entry'
-
-const UUID_PATTERN = /^[0-9a-f]{8}-[0-9a-f]{4}-[1-8][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/
+import { CANONICAL_UUID_PATTERN } from '../domain/primitives'
 
 export function parseJsonObject(raw: string): Record<string, unknown> {
   try {
@@ -24,7 +23,7 @@ export function readCanonicalTapeIncarnationId(row: DeepChatTapeEntryRow): strin
     return null
   }
   const value = parseJsonObject(row.meta_json)[TAPE_INCARNATION_META_KEY]
-  return typeof value === 'string' && UUID_PATTERN.test(value) ? value : null
+  return typeof value === 'string' && CANONICAL_UUID_PATTERN.test(value) ? value : null
 }
 
 export function parseJsonValue(raw: string): unknown {
diff --git a/src/main/tape/application/factPersistence.ts b/src/main/tape/application/factPersistence.ts
index d15a66e74..67d6642a2 100644
--- a/src/main/tape/application/factPersistence.ts
+++ b/src/main/tape/application/factPersistence.ts
@@ -7,7 +7,6 @@ import {
 } from '@/tape/domain/facts'
 import type { DeepChatTapeEntryRow } from '@/tape/domain/entry'
 import type { TapeBootstrapStore, TapeEntryStore } from '@/tape/ports/storage'
-import { buildEffectiveTapeView } from '@/tape/domain/effectiveView'
 import {
   parseAssistantBlocks,
   parseTapeJsonObject,
@@ -612,9 +611,3 @@ export function appendMessageRetractionToTape(
 
   return 1
 }
-
-export function tapeEntriesToEffectiveMessageRecords(
-  rows: DeepChatTapeEntryRow[]
-): ChatMessageRecord[] {
-  return buildEffectiveTapeView(rows, { includePending: true }).messageRecords
-}
diff --git a/src/main/tape/application/factService.ts b/src/main/tape/application/factService.ts
index 09081b3cf..0a961e703 100644
--- a/src/main/tape/application/factService.ts
+++ b/src/main/tape/application/factService.ts
@@ -281,7 +281,7 @@ export class TapeFactService
   }
 
   getMessageRecords(sessionId: string): ChatMessageRecord[] {
-    return buildEffectiveTapeView(this.table.getEffectiveViewInputRows(sessionId), {
+    return buildEffectiveTapeView(this.table.getEffectiveMessageInputRows(sessionId), {
       includePending: true
     }).messageRecords
   }
diff --git a/src/main/tape/application/lineageService.ts b/src/main/tape/application/lineageService.ts
index 567fa2801..9939737cc 100644
--- a/src/main/tape/application/lineageService.ts
+++ b/src/main/tape/application/lineageService.ts
@@ -11,7 +11,8 @@ import {
 } from '../domain/entry'
 import type { TapeApplicationProviders } from '../ports/application'
 import { parseJsonObject, parseJsonValue } from './common'
-import { computeTapeIdentity, TAPE_IDENTITY_PATTERN } from '../domain/tapeIdentity'
+import { SHA256_HEX_PATTERN } from '../domain/primitives'
+import { computeTapeIdentity } from '../domain/tapeIdentity'
 
 type TapeLineageProviders = Pick<
   TapeApplicationProviders,
@@ -141,7 +142,7 @@ function parseSubagentTapeLink(row: DeepChatTapeEntryRow): ParsedSubagentTapeLin
     (linkVersion === 1 && childTapeIdentity === undefined) ||
     (linkVersion === SUBAGENT_TAPE_LINK_VERSION &&
       typeof childTapeIdentity === 'string' &&
-      TAPE_IDENTITY_PATTERN.test(childTapeIdentity))
+      SHA256_HEX_PATTERN.test(childTapeIdentity))
   if (
     row.kind !== 'event' ||
     row.name !== SUBAGENT_TAPE_LINK_EVENT_NAME ||
diff --git a/src/main/tape/application/viewReplayService.ts b/src/main/tape/application/viewReplayService.ts
index 5abd28a7c..14d512d4a 100644
--- a/src/main/tape/application/viewReplayService.ts
+++ b/src/main/tape/application/viewReplayService.ts
@@ -15,7 +15,11 @@ import type {
 } from '@shared/types/tape-replay'
 import { SUMMARY_ANCHOR_NAMES, type DeepChatTapeEntryRow } from '../domain/entry'
 import { buildEffectiveTapeView } from '../domain/effectiveView'
-import { readTapeMessageRetractionId, tapeEntryToMessageRecord } from '../domain/effectiveSemantics'
+import {
+  isEffectiveMessageInputRow,
+  readTapeMessageRetractionId,
+  tapeEntryToMessageRecord
+} from '../domain/effectiveSemantics'
 import {
   collectEntryIds,
   hashString,
@@ -358,12 +362,10 @@ export class TapeViewReplayService {
       }
     }
 
-    const messageSourceRows = rows.filter(
-      (row) => row.kind === 'message' || (row.kind === 'event' && row.name === 'message/retracted')
-    )
-    for (const { entryId, record } of buildEffectiveTapeView(messageSourceRows, {
-      includePending: true
-    }).messageEntries) {
+    for (const { entryId, record } of buildEffectiveTapeView(
+      rows.filter(isEffectiveMessageInputRow),
+      { includePending: true }
+    ).messageEntries) {
       entryIdByMessageId.set(record.id, entryId)
       if (record.role === 'user') {
         messageContentHashByMessageId.set(record.id, hashJsonData(record.content))
diff --git a/src/main/tape/domain/effectiveSemantics.ts b/src/main/tape/domain/effectiveSemantics.ts
index 82a285c74..b4e9a5ab6 100644
--- a/src/main/tape/domain/effectiveSemantics.ts
+++ b/src/main/tape/domain/effectiveSemantics.ts
@@ -1,26 +1,58 @@
 import type { AssistantMessageBlock, ChatMessageRecord } from '@shared/types/agent-interface'
-import type { DeepChatTapeEntryRow } from './entry'
+import type { DeepChatTapeEntryKind, DeepChatTapeEntryRow } from './entry'
 
 const TERMINAL_TAPE_TOOL_STATUSES = new Set(['success', 'error'])
 
+export const TAPE_MESSAGE_RETRACTED_EVENT_NAME = 'message/retracted'
+
+/**
+ * Kinds an effective-state reader may select wholesale. `event` is excluded because the only event
+ * the effective view acts on is `message/retracted`, which every input set already selects by
+ * name (listing `event` would return those rows twice); `context` rows are behavioural evidence
+ * the fold skips outright.
+ */
+export type EffectiveInputKind = Exclude<DeepChatTapeEntryKind, 'event' | 'context'>
+
+/**
+ * Rows that can change effective message/tool state or anchor positions, plus `message/retracted`
+ * events. Every other row (ViewManifests, Journal, provider attempts, contracts, tool-surface
+ * provenance, indicators) is evidence the effective view only passes through, so readers that need
+ * effective state skip it at the store. `TapeEntryStore.getEffectiveViewInputRows` selects by the
+ * same constant.
+ */
+export const EFFECTIVE_VIEW_INPUT_KINDS = [
+  'message',
+  'tool_call',
+  'tool_result',
+  'anchor'
+] as const satisfies readonly EffectiveInputKind[]
+
 /**
- * Rows that can change effective message/tool state or anchor positions. Every other row
- * (ViewManifests, Journal, provider attempts, contracts, tool-surface provenance, indicators) is
- * evidence the effective view only passes through, so readers that need effective state can skip
- * it at the store. Must stay in sync with `TapeEntryStore.getEffectiveViewInputRows`.
+ * The subset that decides `messageRecords`/`messageEntries`: message rows plus the retraction
+ * events that remove them. Tool rows only join onto messages and anchors only pass through, so
+ * readers that need effective messages alone skip both at the store.
+ * `TapeEntryStore.getEffectiveMessageInputRows` selects by the same constant.
  */
+export const EFFECTIVE_MESSAGE_INPUT_KINDS = [
+  'message'
+] as const satisfies readonly EffectiveInputKind[]
+
+function isEffectiveInputRow(
+  row: { kind: string; name: string | null },
+  kinds: readonly string[]
+): boolean {
+  return (
+    kinds.includes(row.kind) ||
+    (row.kind === 'event' && row.name === TAPE_MESSAGE_RETRACTED_EVENT_NAME)
+  )
+}
+
 export function isEffectiveViewInputRow(row: { kind: string; name: string | null }): boolean {
-  switch (row.kind) {
-    case 'message':
-    case 'tool_call':
-    case 'tool_result':
-    case 'anchor':
-      return true
-    case 'event':
-      return row.name === 'message/retracted'
-    default:
-      return false
-  }
+  return isEffectiveInputRow(row, EFFECTIVE_VIEW_INPUT_KINDS)
+}
+
+export function isEffectiveMessageInputRow(row: { kind: string; name: string | null }): boolean {
+  return isEffectiveInputRow(row, EFFECTIVE_MESSAGE_INPUT_KINDS)
 }
 
 export interface DeepChatTapeToolIdentity {
@@ -130,7 +162,7 @@ export function tapeMessageRank(record: ChatMessageRecord, includePending: boole
 }
 
 export function readTapeMessageRetractionId(row: DeepChatTapeEntryRow): string | null {
-  if (row.kind !== 'event' || row.name !== 'message/retracted') {
+  if (row.kind !== 'event' || row.name !== TAPE_MESSAGE_RETRACTED_EVENT_NAME) {
     return null
   }
 
@@ -144,38 +176,46 @@ export function readTapeToolStatus(row: DeepChatTapeEntryRow): string | null {
   return typeof meta.status === 'string' ? meta.status : null
 }
 
-export function tapeToolRank(row: DeepChatTapeEntryRow, includePending: boolean): number {
-  const status = readTapeToolStatus(row)
+export function tapeToolRankFromStatus(status: string | null, includePending: boolean): number {
   if (status === 'pending') {
     return includePending ? 1 : 0
   }
   return status !== null && TERMINAL_TAPE_TOOL_STATUSES.has(status) ? 2 : 0
 }
 
-export function readTapeToolIdentity(row: DeepChatTapeEntryRow): DeepChatTapeToolIdentity | null {
-  if (row.kind !== 'tool_call' && row.kind !== 'tool_result') {
+export function tapeToolRank(row: DeepChatTapeEntryRow, includePending: boolean): number {
+  return tapeToolRankFromStatus(readTapeToolStatus(row), includePending)
+}
+
+/** `readTapeToolIdentity` for a caller that has already parsed `payload_json`. */
+export function readTapeToolIdentityFromPayload(
+  kind: DeepChatTapeEntryRow['kind'],
+  payload: Record<string, unknown>
+): DeepChatTapeToolIdentity | null {
+  if (kind !== 'tool_call' && kind !== 'tool_result') {
     return null
   }
 
-  const payload = parseTapeJsonObject(row.payload_json)
   const messageId = payload.messageId
   if (typeof messageId !== 'string' || messageId.length === 0) {
     return null
   }
 
-  let toolCallId: unknown
-  if (row.kind === 'tool_call') {
-    toolCallId = parseNestedTapeJsonObject(payload.toolCall).id
-  } else {
-    toolCallId = payload.toolCallId
-  }
-
+  const toolCallId =
+    kind === 'tool_call' ? parseNestedTapeJsonObject(payload.toolCall).id : payload.toolCallId
   if (typeof toolCallId !== 'string' || toolCallId.length === 0) {
     return null
   }
 
   return {
-    key: `${row.kind}:${messageId}:${toolCallId}`,
+    key: `${kind}:${messageId}:${toolCallId}`,
     messageId
   }
 }
+
+export function readTapeToolIdentity(row: DeepChatTapeEntryRow): DeepChatTapeToolIdentity | null {
+  if (row.kind !== 'tool_call' && row.kind !== 'tool_result') {
+    return null
+  }
+  return readTapeToolIdentityFromPayload(row.kind, parseTapeJsonObject(row.payload_json))
+}
diff --git a/src/main/tape/domain/effectiveView.ts b/src/main/tape/domain/effectiveView.ts
index 536d3c80a..0667b0799 100644
--- a/src/main/tape/domain/effectiveView.ts
+++ b/src/main/tape/domain/effectiveView.ts
@@ -6,13 +6,15 @@ import { CONTRACT_TAPE_EVENT_NAMES, isContractTapeReservedName } from './contrac
 import { TOOL_SURFACE_TAPE_EVENT_NAMES } from './toolSurfaceFacts'
 import { TAPE_VIEW_MANIFEST_EVENT_NAME } from './viewManifest'
 import {
+  TAPE_MESSAGE_RETRACTED_EVENT_NAME,
   parseNestedTapeJsonObject,
   parseTapeJsonObject,
   readTapeMessageRetractionId,
-  readTapeToolIdentity,
+  readTapeToolIdentityFromPayload,
+  readTapeToolStatus,
   tapeEntryToMessageRecord,
   tapeMessageRank,
-  tapeToolRank
+  tapeToolRankFromStatus
 } from './effectiveSemantics'
 import {
   parseTapeProviderAttemptEvent,
@@ -43,7 +45,7 @@ interface EffectiveTapeViewOptions {
 }
 
 export const DEFAULT_EXCLUDED_TAPE_EVENT_NAMES = [
-  'message/retracted',
+  TAPE_MESSAGE_RETRACTED_EVENT_NAME,
   'message/compaction_indicator',
   'migration/backfill',
   TAPE_COMPACTION_MODEL_CALL_EVENT_NAME,
@@ -60,18 +62,25 @@ type EffectiveMessageCandidate = {
   record: ChatMessageRecord
 }
 
+/** A tool row with everything the fold needs already parsed, so no JSON is parsed twice. */
+type EffectiveToolCandidate = {
+  row: DeepChatTapeEntryRow
+  messageId: string
+  rank: number
+  /** `payload.orderSeq` as stored; when it already matches the message, projection is a no-op. */
+  storedOrderSeq: unknown
+}
+
 export function projectTapeToolOrderSeq(
   row: DeepChatTapeEntryRow,
   effectiveMessageOrderSeqById: ReadonlyMap<string, number>
 ): DeepChatTapeEntryRow {
-  const identity = readTapeToolIdentity(row)
+  const payload = parseTapeJsonObject(row.payload_json)
+  const identity = readTapeToolIdentityFromPayload(row.kind, payload)
   if (!identity) return row
 
   const effectiveOrderSeq = effectiveMessageOrderSeqById.get(identity.messageId)
-  if (effectiveOrderSeq === undefined) return row
-
-  const payload = parseTapeJsonObject(row.payload_json)
-  if (payload.orderSeq === effectiveOrderSeq) return row
+  if (effectiveOrderSeq === undefined || payload.orderSeq === effectiveOrderSeq) return row
   return {
     ...row,
     payload_json: JSON.stringify({ ...payload, orderSeq: effectiveOrderSeq })
@@ -132,23 +141,16 @@ function isAuditEvent(row: DeepChatTapeEntryRow): boolean {
 }
 
 function shouldReplaceToolRow(
-  current: DeepChatTapeEntryRow | undefined,
-  next: DeepChatTapeEntryRow,
-  includePending: boolean
+  current: EffectiveToolCandidate | undefined,
+  next: EffectiveToolCandidate
 ): boolean {
   if (!current) {
     return true
   }
-
-  const currentRank = tapeToolRank(current, includePending)
-  const nextRank = tapeToolRank(next, includePending)
-  if (nextRank > currentRank) {
-    return true
-  }
-  if (nextRank < currentRank) {
-    return false
+  if (next.rank !== current.rank) {
+    return next.rank > current.rank
   }
-  return next.entry_id > current.entry_id
+  return next.row.entry_id > current.row.entry_id
 }
 
 function matchesKinds(
@@ -184,7 +186,7 @@ export function buildEffectiveTapeView(
   const includeAuditEvents = options.includeAuditEvents === true
   const messageCandidates = new Map<string, EffectiveMessageCandidate>()
   const retractedMessageIds = new Set<string>()
-  const toolRows = new Map<string, { row: DeepChatTapeEntryRow; messageId: string }>()
+  const toolCandidates = new Map<string, EffectiveToolCandidate>()
   const anchorRows: DeepChatTapeEntryRow[] = []
   const eventRows: DeepChatTapeEntryRow[] = []
 
@@ -227,13 +229,18 @@ export function buildEffectiveTapeView(
       continue
     }
 
-    const identity = readTapeToolIdentity(row)
-    if (!identity || tapeToolRank(row, includePending) === 0) {
+    const payload = parseTapeJsonObject(row.payload_json)
+    const identity = readTapeToolIdentityFromPayload(row.kind, payload)
+    if (!identity) {
       continue
     }
-    const current = toolRows.get(identity.key)?.row
-    if (shouldReplaceToolRow(current, row, includePending)) {
-      toolRows.set(identity.key, { row, messageId: identity.messageId })
+    const rank = tapeToolRankFromStatus(readTapeToolStatus(row), includePending)
+    if (rank === 0) {
+      continue
+    }
+    const candidate = { row, messageId: identity.messageId, rank, storedOrderSeq: payload.orderSeq }
+    if (shouldReplaceToolRow(toolCandidates.get(identity.key), candidate)) {
+      toolCandidates.set(identity.key, candidate)
     }
   }
 
@@ -244,13 +251,21 @@ export function buildEffectiveTapeView(
         left.record.orderSeq - right.record.orderSeq ||
         compareSqliteBinaryText(left.record.id, right.record.id)
     )
-  const effectiveMessageIds = new Set(messageRows.map((candidate) => candidate.record.id))
   const effectiveMessageOrderSeqById = new Map(
     messageRows.map((candidate) => [candidate.record.id, candidate.record.orderSeq])
   )
-  const effectiveToolRows = [...toolRows.values()]
-    .filter((candidate) => effectiveMessageIds.has(candidate.messageId))
-    .map((candidate) => projectTapeToolOrderSeq(candidate.row, effectiveMessageOrderSeqById))
+  // Tool rows only survive when their message did; the stored orderSeq matches unless a
+  // compaction shift moved the message, so the re-serialising projection is the rare path.
+  const effectiveToolRows: DeepChatTapeEntryRow[] = []
+  for (const candidate of toolCandidates.values()) {
+    const effectiveOrderSeq = effectiveMessageOrderSeqById.get(candidate.messageId)
+    if (effectiveOrderSeq === undefined) continue
+    effectiveToolRows.push(
+      candidate.storedOrderSeq === effectiveOrderSeq
+        ? candidate.row
+        : projectTapeToolOrderSeq(candidate.row, effectiveMessageOrderSeqById)
+    )
+  }
   const effectiveRows = [
     ...anchorRows,
     ...eventRows,
diff --git a/src/main/tape/domain/executionContract.ts b/src/main/tape/domain/executionContract.ts
index d656da985..166f289a5 100644
--- a/src/main/tape/domain/executionContract.ts
+++ b/src/main/tape/domain/executionContract.ts
@@ -31,6 +31,13 @@ import {
 } from '@shared/types/execution-contract'
 import type { DeepChatTaskContractContext } from '@shared/types/task-contract'
 import { canonicalJsonStringifyData, hashJsonData } from './canonicalJson'
+import {
+  canonicalUuid,
+  compareUtf16,
+  deepFreeze,
+  SHA256_HEX_PATTERN,
+  utf8Length
+} from './primitives'
 import { isDeepChatTaskContract, isDeepChatTaskContractRef } from './taskContract'
 import {
   isWorkspacePathWithin,
@@ -49,8 +56,6 @@ const MAX_SOURCE_REF_BYTES = 2_048
 const MAX_WORKSPACE_PATH_BYTES = 32 * 1_024
 const MAX_ASSEMBLER_VERSION_BYTES = 256
 const MAX_SECTION_DEGRADATION_CODES = 16
-const UUID_PATTERN = /^[0-9a-f]{8}-[0-9a-f]{4}-[1-8][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i
-const SHA_256_PATTERN = /^[0-9a-f]{64}$/
 const JSON_HASH_OPTIONS = Object.freeze({ omitUndefinedProperties: true })
 const PROMPT_SECTION_KINDS = new Set<string>(DEEPCHAT_PROMPT_SECTION_KINDS)
 const PROMPT_SECTION_INCLUSIONS = new Set<string>(DEEPCHAT_PROMPT_SECTION_INCLUSIONS)
@@ -218,10 +223,6 @@ export function restoreExecutionContract(value: unknown): DeepChatExecutionContr
   return isDeepChatExecutionContract(value) ? deepFreeze(value) : null
 }
 
-function utf8Length(value: string): number {
-  return Buffer.byteLength(value, 'utf8')
-}
-
 function requireString(
   value: unknown,
   label: string,
@@ -246,15 +247,15 @@ function requireString(
 }
 
 function requireUuid(value: unknown, label: string): string {
-  const uuid = requireString(value, label, MAX_IDENTITY_BYTES)
-  if (!UUID_PATTERN.test(uuid)) {
+  const uuid = canonicalUuid(requireString(value, label, MAX_IDENTITY_BYTES))
+  if (!uuid) {
     throw new ExecutionContractError(`${label} must be a UUID.`, 'invalid_input')
   }
-  return uuid.toLowerCase()
+  return uuid
 }
 
 function requireSha256(value: unknown, label: string): string {
-  if (typeof value !== 'string' || !SHA_256_PATTERN.test(value)) {
+  if (typeof value !== 'string' || !SHA256_HEX_PATTERN.test(value)) {
     throw new ExecutionContractError(`${label} must be a lowercase SHA-256 hash.`, 'invalid_input')
   }
   return value
@@ -335,11 +336,7 @@ function matchesNormalizedUuid(value: unknown, label: string): value is string {
 }
 
 function isSha256(value: unknown): value is string {
-  return typeof value === 'string' && SHA_256_PATTERN.test(value)
-}
-
-function compareCodePoints(left: string, right: string): number {
-  return left < right ? -1 : left > right ? 1 : 0
+  return typeof value === 'string' && SHA256_HEX_PATTERN.test(value)
 }
 
 function normalizeExecution(value: ToolExecutionContract, label: string): ToolExecutionContract {
@@ -490,7 +487,7 @@ function normalizeToolCeilings(
   })
 
   return [...ceilingByTarget.entries()]
-    .sort(([left], [right]) => compareCodePoints(left, right))
+    .sort(([left], [right]) => compareUtf16(left, right))
     .map(([, value]) => value.ceiling)
 }
 
@@ -532,7 +529,7 @@ function normalizePromptSections(
     if (degradationCodes.some((code) => !PROMPT_DEGRADATION_CODES.has(code))) {
       throw new ExecutionContractError(`${label}.degradationCodes is invalid.`, 'invalid_input')
     }
-    degradationCodes.sort(compareCodePoints)
+    degradationCodes.sort(compareUtf16)
     if (section.freshness !== undefined && !PROMPT_SOURCE_FRESHNESS_VALUES.has(section.freshness)) {
       throw new ExecutionContractError(`${label}.freshness is invalid.`, 'invalid_input')
     }
@@ -726,7 +723,7 @@ function isStoredPromptSection(value: unknown): value is DeepChatPromptSectionPr
         (code, index) =>
           typeof code !== 'string' ||
           !PROMPT_DEGRADATION_CODES.has(code) ||
-          (index > 0 && compareCodePoints(degradationCodes[index - 1], code) >= 0)
+          (index > 0 && compareUtf16(degradationCodes[index - 1], code) >= 0)
       )
     ) {
       return false
@@ -779,7 +776,7 @@ function isStoredExecutionCeilings(value: unknown): value is DeepChatExecutionCo
       return false
     }
     const targetKey = buildExecutionToolTargetKey(tool.target)
-    if (previousTargetKey !== null && compareCodePoints(previousTargetKey, targetKey) >= 0) {
+    if (previousTargetKey !== null && compareUtf16(previousTargetKey, targetKey) >= 0) {
       return false
     }
     const previousVisibleTarget = targetKeyByVisibleName.get(tool.target.providerVisibleName)
@@ -1041,14 +1038,6 @@ export function assertExecutionContractAllowsDispatch(
   }
 }
 
-function deepFreeze<T>(value: T): T {
-  if (!value || typeof value !== 'object' || Object.isFrozen(value)) return value
-  for (const nested of Object.values(value as Record<string, unknown>)) {
-    deepFreeze(nested)
-  }
-  return Object.freeze(value)
-}
-
 function buildContractHash(contract: Omit<DeepChatExecutionContract, 'contractHash'>): string {
   return hashData(contract, 'execution contract')
 }
@@ -1112,7 +1101,7 @@ export function verifyExecutionContractHash(contract: DeepChatExecutionContract)
     contract?.schemaVersion !== DEEPCHAT_EXECUTION_CONTRACT_SCHEMA_VERSION ||
     contract?.hashVersion !== DEEPCHAT_EXECUTION_CONTRACT_HASH_VERSION ||
     typeof contract.contractHash !== 'string' ||
-    !SHA_256_PATTERN.test(contract.contractHash)
+    !SHA256_HEX_PATTERN.test(contract.contractHash)
   ) {
     return false
   }
diff --git a/src/main/tape/domain/executionJournal.ts b/src/main/tape/domain/executionJournal.ts
index 68dfbf81b..ae48279ac 100644
--- a/src/main/tape/domain/executionJournal.ts
+++ b/src/main/tape/domain/executionJournal.ts
@@ -1,5 +1,6 @@
 import type { DeepChatTapeEntryRow } from './entry'
 import { hashJson, hashJsonData, stableJsonStringify } from './canonicalJson'
+import { canonicalUuid, SHA256_HEX_PATTERN } from './primitives'
 export const EXECUTION_JOURNAL_PROTOCOL_VERSION = 1 as const
 export const EXECUTION_JOURNAL_NESTED_PROTOCOL_VERSION = 2 as const
 export const MAX_EXECUTION_JOURNAL_NESTED_CHILDREN = 128
@@ -33,8 +34,6 @@ const MAX_IDENTITY_CHARS = 1_024
 export const MAX_EXECUTION_JOURNAL_TOOL_NAME_CHARACTERS = 512
 const MAX_TARGET_FIELD_CHARS = 1_024
 const MAX_STOP_REASON_CHARS = 1_024
-const SHA_256_PATTERN = /^[0-9a-f]{64}$/
-const UUID_PATTERN = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i
 
 export interface ExecutionOperationIdentity {
   runId: string
@@ -287,11 +286,11 @@ function requireMessageId(value: unknown): string {
 }
 
 export function requireExecutionRunId(value: unknown): string {
-  const runId = requireString(value, 'runId', MAX_IDENTITY_CHARS)
-  if (!UUID_PATTERN.test(runId)) {
+  const runId = canonicalUuid(requireString(value, 'runId', MAX_IDENTITY_CHARS))
+  if (!runId) {
     throw new ExecutionJournalError('runId must be a UUID.', 'invalid_fact')
   }
-  return runId.toLowerCase()
+  return runId
 }
 
 function requireRequestSeq(value: unknown): number {
@@ -435,7 +434,7 @@ function requireProtocolVersion(value: unknown): ExecutionJournalProtocolVersion
 }
 
 function requireHash(value: unknown, label: string): string {
-  if (typeof value !== 'string' || !SHA_256_PATTERN.test(value)) {
+  if (typeof value !== 'string' || !SHA256_HEX_PATTERN.test(value)) {
     throw new ExecutionJournalError(`${label} must be a lowercase SHA-256 hash.`, 'invalid_fact')
   }
   return value
diff --git a/src/main/tape/domain/primitives.ts b/src/main/tape/domain/primitives.ts
new file mode 100644
index 000000000..f6758e8e7
--- /dev/null
+++ b/src/main/tape/domain/primitives.ts
@@ -0,0 +1,36 @@
+/** Lower-case SHA-256 hex digest; the shape every stored Tape hash is validated against. */
+export const SHA256_HEX_PATTERN = /^[0-9a-f]{64}$/
+
+/**
+ * RFC 9562 UUID (versions 1-8) in canonical lower-case form; the shape every UUID identity is
+ * stored in. Validate stored values against it directly; normalise input with `canonicalUuid`.
+ */
+export const CANONICAL_UUID_PATTERN =
+  /^[0-9a-f]{8}-[0-9a-f]{4}-[1-8][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/
+
+/** The canonical form of a UUID given in any letter case, or null when it is not a UUID. */
+export function canonicalUuid(value: string): string | null {
+  const lower = value.toLowerCase()
+  return CANONICAL_UUID_PATTERN.test(lower) ? lower : null
+}
+
+/** Tape size limits are byte limits on the UTF-8 encoding, not JavaScript string lengths. */
+export function utf8Length(value: string): number {
+  return Buffer.byteLength(value, 'utf8')
+}
+
+/**
+ * Orders strings by UTF-16 code unit, which is what `<` does. Canonical key and target orderings
+ * inside persisted facts are defined on this comparison; a locale or code-point compare would
+ * reorder existing hashes.
+ */
+export function compareUtf16(left: string, right: string): number {
+  return left < right ? -1 : left > right ? 1 : 0
+}
+
+/** Freezes a plain-data tree in place and returns it; already-frozen subtrees are not revisited. */
+export function deepFreeze<T>(value: T): T {
+  if (!value || typeof value !== 'object' || Object.isFrozen(value)) return value
+  for (const nested of Object.values(value as Record<string, unknown>)) deepFreeze(nested)
+  return Object.freeze(value)
+}
diff --git a/src/main/tape/domain/replay.ts b/src/main/tape/domain/replay.ts
index 27952e458..6bd1e2adb 100644
--- a/src/main/tape/domain/replay.ts
+++ b/src/main/tape/domain/replay.ts
@@ -8,6 +8,7 @@ import { isDeepChatExecutionContract } from './executionContract'
 import { hashJson } from './viewManifest'
 import { validateSchema6SkillContexts, validateSchema7SkillContexts } from './skillContext'
 import { isBoundedSkillTapeIdentity } from './skillIdentity'
+import { SHA256_HEX_PATTERN } from './primitives'
 
 const VIEW_POLICIES = new Set([
   'cache_aware_context_v2',
@@ -36,7 +37,6 @@ const SCHEMA_V3_ENTRY_REASONS = new Set([
   'reconstruction_checkpoint',
   'memory_context'
 ])
-const SHA256_HEX_PATTERN = /^[a-f0-9]{64}$/
 
 const VIEW_EXCLUDED_REASONS = new Set([
   'before_summary_cursor',
diff --git a/src/main/tape/domain/skillContext.ts b/src/main/tape/domain/skillContext.ts
index 3823818f3..e3dafc536 100644
--- a/src/main/tape/domain/skillContext.ts
+++ b/src/main/tape/domain/skillContext.ts
@@ -16,8 +16,8 @@ import {
 } from './executionJournal'
 import { hashJsonData } from './canonicalJson'
 import { isBoundedSkillTapeIdentity } from './skillIdentity'
+import { SHA256_HEX_PATTERN } from './primitives'
 
-const HASH = /^[a-f0-9]{64}$/
 const MAX_SOURCE_REFS = 64
 export const MAX_SKILL_CONTEXTS_PER_VIEW = 64
 export const MAX_SKILL_VIEW_RESULT_FACT_BYTES = SKILL_RUNTIME_VIEW_RESULT_MAX_BYTES
@@ -219,7 +219,7 @@ function validateMaterializationRef(
     !isSkillSourceType(ref.sourceType) ||
     !isBoundedSkillTapeIdentity(ref.sourceId) ||
     !isBoundedSkillTapeIdentity(ref.skillName) ||
-    !HASH.test(ref.effectiveContentHash) ||
+    !SHA256_HEX_PATTERN.test(ref.effectiveContentHash) ||
     (projectedContentHash !== undefined && projectedContentHash !== ref.effectiveContentHash) ||
     ref.agentId !== context.agentId ||
     ref.sourceType !== context.sourceType ||
@@ -270,7 +270,7 @@ function validateSkillContexts(
       !ref ||
       !positive(ref.entryId) ||
       typeof context.projectedContentHash !== 'string' ||
-      !HASH.test(context.projectedContentHash) ||
+      !SHA256_HEX_PATTERN.test(context.projectedContentHash) ||
       !positive(context.projectionVersion) ||
       !Array.isArray(context.sourceEntryIds) ||
       context.sourceEntryIds.length > MAX_SOURCE_REFS ||
@@ -296,7 +296,7 @@ function validateSkillContexts(
         context.providerRole !== 'tool' ||
         ref.kind !== 'tool_result' ||
         typeof ref.contentHash !== 'string' ||
-        !HASH.test(ref.contentHash) ||
+        !SHA256_HEX_PATTERN.test(ref.contentHash) ||
         context.projectedContentHash !== ref.contentHash ||
         context.deduplicationSource !== 'runtime_view'
       )
diff --git a/src/main/tape/domain/skillMaterialization.ts b/src/main/tape/domain/skillMaterialization.ts
index 21ca83049..9d5028873 100644
--- a/src/main/tape/domain/skillMaterialization.ts
+++ b/src/main/tape/domain/skillMaterialization.ts
@@ -18,6 +18,7 @@ import {
 } from '@shared/types/skill'
 import type { DeepChatTapeEntryRow } from './entry'
 import { isBoundedSkillTapeIdentity, MAX_SKILL_TAPE_IDENTITY_BYTES } from './skillIdentity'
+import { SHA256_HEX_PATTERN } from './primitives'
 
 export const SKILL_MATERIALIZATION_NAME = 'skill/materialized' as const
 export const SKILL_MATERIALIZATION_SCHEMA_VERSION = 3 as const
@@ -32,8 +33,6 @@ export const MAX_SKILL_MATERIALIZATION_PACKAGE_BATCH_ENCODED_BYTES =
 const MAX_SKILL_MATERIALIZATION_STORED_PAYLOAD_BYTES =
   SKILL_EFFECTIVE_CONTENT_MAX_BYTES * 6 + SKILL_EXECUTION_PACKAGE_MAX_ENCODED_BYTES + 64 * 1024
 
-const SHA256 = /^[a-f0-9]{64}$/
-
 export interface TapeSkillIdentity {
   agentId: string
   sourceType: SkillSourceType
@@ -99,7 +98,7 @@ function requireIdentity(value: unknown, field: string): string {
 }
 
 function requireHash(value: unknown, field: string): string {
-  if (typeof value !== 'string' || !SHA256.test(value)) {
+  if (typeof value !== 'string' || !SHA256_HEX_PATTERN.test(value)) {
     throw new TypeError(`${field} must be a lowercase SHA-256 hash.`)
   }
   return value
diff --git a/src/main/tape/domain/tapeIdentity.ts b/src/main/tape/domain/tapeIdentity.ts
index 56b71a527..dfab914ef 100644
--- a/src/main/tape/domain/tapeIdentity.ts
+++ b/src/main/tape/domain/tapeIdentity.ts
@@ -1,8 +1,6 @@
 import { createHash } from 'node:crypto'
 import type { DeepChatTapeEntryRow } from './entry'
 
-export const TAPE_IDENTITY_PATTERN = /^[a-f0-9]{64}$/u
-
 export function computeTapeIdentity(row: DeepChatTapeEntryRow): string {
   return createHash('sha256')
     .update(
diff --git a/src/main/tape/domain/taskContract.ts b/src/main/tape/domain/taskContract.ts
index 46764e395..43f98afbd 100644
--- a/src/main/tape/domain/taskContract.ts
+++ b/src/main/tape/domain/taskContract.ts
@@ -1,4 +1,3 @@
-import { Buffer } from 'node:buffer'
 import {
   DEEPCHAT_TASK_CONTRACT_HASH_VERSION,
   DEEPCHAT_TASK_CONTRACT_SCHEMA_VERSION,
@@ -11,6 +10,7 @@ import {
   type DeepChatTaskWorkspaceCeiling
 } from '@shared/types/task-contract'
 import { canonicalJsonStringifyData, hashJsonData } from './canonicalJson'
+import { compareUtf16, deepFreeze, SHA256_HEX_PATTERN, utf8Length } from './primitives'
 import { normalizeAbsoluteWorkspacePath } from './workspacePath'
 
 const MAX_IDENTITY_BYTES = 1_024
@@ -20,7 +20,6 @@ const MAX_SECTION_NAME_BYTES = 256
 const MAX_WORKSPACE_PATH_BYTES = 32 * 1024
 const MAX_TASK_INPUT_BYTES = 64 * 1024
 const MAX_SUBAGENT_DEPTH = 1
-const SHA_256_PATTERN = /^[0-9a-f]{64}$/u
 
 const TASK_CONTRACT_KEYS = [
   'schemaVersion',
@@ -69,10 +68,6 @@ export class TaskContractError extends Error {
   }
 }
 
-function utf8Length(value: string): number {
-  return Buffer.byteLength(value, 'utf8')
-}
-
 function requireString(
   value: unknown,
   label: string,
@@ -111,10 +106,6 @@ function requireNonNegativeSafeInteger(value: unknown, label: string): number {
   return value as number
 }
 
-function compareCodePoints(left: string, right: string): number {
-  return left < right ? -1 : left > right ? 1 : 0
-}
-
 function normalizeWorkspace(workspace: DeepChatTaskWorkspaceCeiling): DeepChatTaskWorkspaceCeiling {
   if (workspace?.kind === 'runtime_default') return { kind: 'runtime_default' }
   if (workspace?.kind !== 'path' || typeof workspace.path !== 'string') {
@@ -143,8 +134,8 @@ function normalizeEvaluationRef(value: DeepChatEvaluationRef | null): DeepChatEv
   const entryId = requirePositiveSafeInteger(value?.entryId, 'predecessorEvaluationRef.entryId')
   if (
     value?.schemaVersion !== 1 ||
-    !SHA_256_PATTERN.test(value.tapeIdentity) ||
-    !SHA_256_PATTERN.test(value.evaluationHash)
+    !SHA256_HEX_PATTERN.test(value.tapeIdentity) ||
+    !SHA256_HEX_PATTERN.test(value.evaluationHash)
   ) {
     throw new TaskContractError('predecessorEvaluationRef is invalid.', 'invalid_input')
   }
@@ -207,16 +198,10 @@ function normalizeHandoffFormat(
     if (sections.length === 0 || sections.length > MAX_TASK_CONTRACT_REQUIREMENTS) {
       throw new TaskContractError(`${label}.sections has an invalid size.`, 'invalid_input')
     }
-    sections.sort(compareCodePoints)
+    sections.sort(compareUtf16)
     return { id, kind: 'required_sections' as const, level: 2 as const, sections }
   })
-  return normalized.sort((left, right) => compareCodePoints(left.id, right.id))
-}
-
-function deepFreeze<T>(value: T): T {
-  if (!value || typeof value !== 'object' || Object.isFrozen(value)) return value
-  for (const nested of Object.values(value as Record<string, unknown>)) deepFreeze(nested)
-  return Object.freeze(value)
+  return normalized.sort((left, right) => compareUtf16(left.id, right.id))
 }
 
 function hasExactKeys(value: unknown, keys: readonly string[]): value is Record<string, unknown> {
@@ -319,7 +304,7 @@ export function isDeepChatTaskContract(value: unknown): value is DeepChatTaskCon
     value.schemaVersion !== DEEPCHAT_TASK_CONTRACT_SCHEMA_VERSION ||
     value.hashVersion !== DEEPCHAT_TASK_CONTRACT_HASH_VERSION ||
     typeof value.contractHash !== 'string' ||
-    !SHA_256_PATTERN.test(value.contractHash)
+    !SHA256_HEX_PATTERN.test(value.contractHash)
   ) {
     return false
   }
@@ -365,9 +350,9 @@ export function isDeepChatTaskContractRef(value: unknown): value is DeepChatTask
       requireString(value.sessionId, 'TaskContractRef.sessionId', MAX_IDENTITY_BYTES, 256) ===
         value.sessionId &&
       typeof value.tapeIdentity === 'string' &&
-      SHA_256_PATTERN.test(value.tapeIdentity) &&
+      SHA256_HEX_PATTERN.test(value.tapeIdentity) &&
       typeof value.contractHash === 'string' &&
-      SHA_256_PATTERN.test(value.contractHash) &&
+      SHA256_HEX_PATTERN.test(value.contractHash) &&
       requirePositiveSafeInteger(value.entryId, 'TaskContractRef.entryId') === value.entryId
     )
   } catch {
diff --git a/src/main/tape/domain/taskEvaluation.ts b/src/main/tape/domain/taskEvaluation.ts
index 4bba818ef..6e26c805f 100644
--- a/src/main/tape/domain/taskEvaluation.ts
+++ b/src/main/tape/domain/taskEvaluation.ts
@@ -26,9 +26,9 @@ import {
 } from '@shared/types/task-contract'
 import { indexMarkdownLevelTwoSections } from '@shared/orchestration/liveDelegationMarkdown'
 import { canonicalJsonStringifyData, hashJsonData } from './canonicalJson'
+import { compareUtf16, deepFreeze, SHA256_HEX_PATTERN } from './primitives'
 import { isDeepChatTaskContract } from './taskContract'
 
-const SHA_256_PATTERN = /^[0-9a-f]{64}$/u
 const SUCCESS_REASON_CODES = new Set<DeepChatTaskEvaluationReasonCode>([
   'required_sections_present'
 ])
@@ -105,7 +105,7 @@ export function buildTaskEvaluation(input: BuildTaskEvaluationInput): DeepChatTa
       : 'valid'
   const reasonCodes = [
     ...new Set(records.filter((record) => record.outcome !== 'valid').map((record) => record.code))
-  ].sort(compareCodePoints)
+  ].sort(compareUtf16)
 
   return finalizeEvaluation({
     schemaVersion: DEEPCHAT_TASK_EVALUATION_SCHEMA_VERSION,
@@ -179,11 +179,11 @@ export function isDeepChatEvaluationRef(value: unknown): value is DeepChatEvalua
     ref.sessionId.length > 0 &&
     ref.sessionId.length <= 256 &&
     typeof ref.tapeIdentity === 'string' &&
-    SHA_256_PATTERN.test(ref.tapeIdentity) &&
+    SHA256_HEX_PATTERN.test(ref.tapeIdentity) &&
     Number.isSafeInteger(ref.entryId) &&
     (ref.entryId as number) > 0 &&
     typeof ref.evaluationHash === 'string' &&
-    SHA_256_PATTERN.test(ref.evaluationHash)
+    SHA256_HEX_PATTERN.test(ref.evaluationHash)
   )
 }
 
@@ -345,7 +345,7 @@ function isCanonicalEvaluation(evaluation: DeepChatTaskEvaluation): boolean {
   if (evaluation.reasonCodes.some((code) => SUCCESS_REASON_CODES.has(code))) return false
   if (
     canonicalJsonStringifyData(evaluation.reasonCodes) !==
-    canonicalJsonStringifyData([...new Set(evaluation.reasonCodes)].sort(compareCodePoints))
+    canonicalJsonStringifyData([...new Set(evaluation.reasonCodes)].sort(compareUtf16))
   ) {
     return false
   }
@@ -353,7 +353,7 @@ function isCanonicalEvaluation(evaluation: DeepChatTaskEvaluation): boolean {
     ...new Set(
       evaluation.records.filter((record) => record.outcome !== 'valid').map((record) => record.code)
     )
-  ].sort(compareCodePoints)
+  ].sort(compareUtf16)
   if (
     evaluation.omittedRecordCount === 0 &&
     canonicalJsonStringifyData(evaluation.reasonCodes) !==
@@ -380,7 +380,7 @@ function isCanonicalLegacyEvaluation(evaluation: DeepChatLegacyTaskEvaluation):
   if (evaluation.reasonCodes.some((code) => LEGACY_SUCCESS_REASON_CODES.has(code))) return false
   if (
     canonicalJsonStringifyData(evaluation.reasonCodes) !==
-    canonicalJsonStringifyData([...new Set(evaluation.reasonCodes)].sort(compareCodePoints))
+    canonicalJsonStringifyData([...new Set(evaluation.reasonCodes)].sort(compareUtf16))
   ) {
     return false
   }
@@ -390,7 +390,7 @@ function isCanonicalLegacyEvaluation(evaluation: DeepChatLegacyTaskEvaluation):
         .filter((record) => record.outcome !== 'passed')
         .map((record) => record.code)
     )
-  ].sort(compareCodePoints)
+  ].sort(compareUtf16)
   if (
     evaluation.omittedRecordCount === 0 &&
     canonicalJsonStringifyData(evaluation.reasonCodes) !==
@@ -450,7 +450,7 @@ function legacyEvaluationMatchesWriterState(evaluation: DeepChatLegacyTaskEvalua
       record.requirementKind !== 'required_sections' ||
       requirementIds.has(record.requirementId) ||
       (previousRequirementId !== null &&
-        compareCodePoints(previousRequirementId, record.requirementId) >= 0)
+        compareUtf16(previousRequirementId, record.requirementId) >= 0)
     ) {
       return false
     }
@@ -532,13 +532,3 @@ function reasonCodeOutcome(
   if (code === 'required_sections_missing') return 'invalid'
   return 'indeterminate'
 }
-
-function compareCodePoints(left: string, right: string): number {
-  return left < right ? -1 : left > right ? 1 : 0
-}
-
-function deepFreeze<T>(value: T): T {
-  if (!value || typeof value !== 'object' || Object.isFrozen(value)) return value
-  for (const nested of Object.values(value as Record<string, unknown>)) deepFreeze(nested)
-  return Object.freeze(value)
-}
diff --git a/src/main/tape/domain/toolSurfaceFacts.ts b/src/main/tape/domain/toolSurfaceFacts.ts
index ed68fa84d..c92e1af64 100644
--- a/src/main/tape/domain/toolSurfaceFacts.ts
+++ b/src/main/tape/domain/toolSurfaceFacts.ts
@@ -12,6 +12,7 @@ import type { DeepChatExecutionToolTargetIdentity } from '@shared/types/executio
 import type { DeepChatTaskContractRef } from '@shared/types/task-contract'
 import { canonicalJsonStringifyData, hashJsonData } from './canonicalJson'
 import { buildExecutionToolTargetKey, isDetachedStoredToolTarget } from './executionContract'
+import { CANONICAL_UUID_PATTERN, compareUtf16, deepFreeze, SHA256_HEX_PATTERN } from './primitives'
 import { isDeepChatTaskContractRef } from './taskContract'
 import { normalizeAbsoluteWorkspacePath } from './workspacePath'
 
@@ -62,8 +63,6 @@ const MAX_VERSION_BYTES = 256
 const MAX_PROGRAMMATIC_POLICY_VERSION_BYTES = MAX_IDENTITY_BYTES
 const MAX_PLAIN_DATA_DEPTH = 64
 const MAX_PLAIN_DATA_NODES = 100_000
-const UUID_PATTERN = /^[0-9a-f]{8}-[0-9a-f]{4}-[1-8][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/
-const SHA_256_PATTERN = /^[a-f0-9]{64}$/
 const MODEL_EXPOSURES = new Set<AgentToolExposure>(['user-configurable', 'system-model'])
 const TOOL_SURFACE_ADAPTER_MODES = new Set<TapeToolSurfaceAdapterMode>([
   'direct-native',
@@ -454,11 +453,11 @@ function isNormalizedBoundedString(value: unknown, maxBytes = MAX_IDENTITY_BYTES
 }
 
 function isHash(value: unknown): value is string {
-  return typeof value === 'string' && SHA_256_PATTERN.test(value)
+  return typeof value === 'string' && SHA256_HEX_PATTERN.test(value)
 }
 
 function isUuid(value: unknown): value is string {
-  return typeof value === 'string' && UUID_PATTERN.test(value)
+  return typeof value === 'string' && CANONICAL_UUID_PATTERN.test(value)
 }
 
 function isToolSurfaceAdapterMode(value: unknown): value is TapeToolSurfaceAdapterMode {
@@ -536,10 +535,6 @@ function cloneCatalogEntry(entry: TapeToolCatalogSourceEntry): TapeToolCatalogSo
   return cloneCatalogEntryFields(entry)
 }
 
-function compareCodePoints(left: string, right: string): number {
-  return left < right ? -1 : left > right ? 1 : 0
-}
-
 function catalogProjectionHash(input: {
   fullCatalogHash: string
   totalEntryCount: number
@@ -633,12 +628,6 @@ function findLargestFittingPrefix(maximum: number, build: (length: number) => un
   return lower
 }
 
-function deepFreeze<T>(value: T): T {
-  if (!value || typeof value !== 'object' || Object.isFrozen(value)) return value
-  for (const nested of Object.values(value as Record<string, unknown>)) deepFreeze(nested)
-  return Object.freeze(value)
-}
-
 export function createTapeToolCatalogFact(
   input: CreateTapeToolCatalogFactInput
 ): TapeToolCatalogFact {
@@ -662,7 +651,7 @@ function createTapeToolCatalogFactFromData(
 
   const entries = input.entries
     .map(cloneCatalogEntry)
-    .sort((left, right) => compareCodePoints(left.stableTargetKey, right.stableTargetKey))
+    .sort((left, right) => compareUtf16(left.stableTargetKey, right.stableTargetKey))
   const targetByVisibleName = new Map<string, string>()
   for (let index = 0; index < entries.length; index += 1) {
     if (index > 0 && entries[index - 1].stableTargetKey === entries[index].stableTargetKey) {
@@ -749,7 +738,7 @@ function isCatalogFactShape(value: unknown): value is TapeToolCatalogFact {
   for (let index = 0; index < value.entries.length; index += 1) {
     if (
       index > 0 &&
-      compareCodePoints(
+      compareUtf16(
         value.entries[index - 1].stableTargetKey,
         value.entries[index].stableTargetKey
       ) >= 0
@@ -1102,7 +1091,7 @@ function compareSearchRefs(
     left.originRequestSeq - right.originRequestSeq ||
     left.toolCallOrdinalWithinBatch - right.toolCallOrdinalWithinBatch ||
     left.resultRank - right.resultRank ||
-    compareCodePoints(left.stableTargetKey, right.stableTargetKey)
+    compareUtf16(left.stableTargetKey, right.stableTargetKey)
   )
 }
 
@@ -1201,8 +1190,8 @@ function requireCompleteAcceptedSearchProvenance(
   const expectedTargets = activeEntries
     .filter((entry) => entry.reason === 'search-result')
     .map((entry) => entry.stableTargetKey)
-    .sort(compareCodePoints)
-  const actualTargets = searchResultRefs.map((ref) => ref.stableTargetKey).sort(compareCodePoints)
+    .sort(compareUtf16)
+  const actualTargets = searchResultRefs.map((ref) => ref.stableTargetKey).sort(compareUtf16)
   if (canonicalJsonStringifyData(expectedTargets) !== canonicalJsonStringifyData(actualTargets)) {
     throw new TypeError('Tool surface is missing accepted ToolSearch result provenance.')
   }
@@ -1717,7 +1706,7 @@ function validateProgrammaticEntries(entries: readonly TapeToolCatalogSourceEntr
       )
     }
     if (index > 0) {
-      const order = compareCodePoints(entries[index - 1].stableTargetKey, entry.stableTargetKey)
+      const order = compareUtf16(entries[index - 1].stableTargetKey, entry.stableTargetKey)
       if (order === 0) {
         throw new TypeError('Programmatic Tool Surface contains a duplicate stable target.')
       }
@@ -1785,7 +1774,7 @@ export function createTapeProgrammaticToolSurfaceFact(
   }
   const entries = data.entries
     .map(cloneCatalogEntry)
-    .sort((left, right) => compareCodePoints(left.stableTargetKey, right.stableTargetKey))
+    .sort((left, right) => compareUtf16(left.stableTargetKey, right.stableTargetKey))
   validateProgrammaticEntries(entries)
   if (
     buildProgrammaticToolSurfaceHashV1({
diff --git a/src/main/tape/domain/viewManifest.ts b/src/main/tape/domain/viewManifest.ts
index 07996e106..ff0057e4a 100644
--- a/src/main/tape/domain/viewManifest.ts
+++ b/src/main/tape/domain/viewManifest.ts
@@ -23,6 +23,7 @@ import type {
 import { validateSchema6SkillContexts, validateSchema7SkillContexts } from './skillContext'
 import { estimateMessagesTokens } from '@shared/utils/messageTokens'
 import { hashJson, hashJsonData } from './canonicalJson'
+import { SHA256_HEX_PATTERN } from './primitives'
 import {
   buildProviderMessagesHash,
   buildProviderVisibleToolDefinitionsHash,
@@ -50,7 +51,6 @@ export function isCompactionRecord(record: ChatMessageRecord): boolean {
 /** Stable event name persisted for deterministic view reconstruction. */
 export const TAPE_VIEW_MANIFEST_EVENT_NAME = 'view/assembled'
 export const TAPE_VIEW_CONTEXT_BUILDER_VERSION = 'cache-aware-v2' as const
-const SHA256_HEX_PATTERN = /^[a-f0-9]{64}$/
 
 export function getTapeViewManifestExecutionContract(
   manifest: DeepChatTapeViewManifest
diff --git a/src/main/tape/infrastructure/sqlite/tapeEntryStore.ts b/src/main/tape/infrastructure/sqlite/tapeEntryStore.ts
index 034557156..e1a067d11 100644
--- a/src/main/tape/infrastructure/sqlite/tapeEntryStore.ts
+++ b/src/main/tape/infrastructure/sqlite/tapeEntryStore.ts
@@ -16,7 +16,13 @@ import {
   type TapeEventAppendInput
 } from '@/tape/domain/entry'
 import { DEFAULT_EXCLUDED_TAPE_EVENT_NAMES } from '@/tape/domain/effectiveView'
-import { parseTapeJsonObject } from '@/tape/domain/effectiveSemantics'
+import {
+  EFFECTIVE_MESSAGE_INPUT_KINDS,
+  EFFECTIVE_VIEW_INPUT_KINDS,
+  TAPE_MESSAGE_RETRACTED_EVENT_NAME,
+  parseTapeJsonObject,
+  type EffectiveInputKind
+} from '@/tape/domain/effectiveSemantics'
 import {
   EXECUTION_JOURNAL_EVENT_NAMES,
   type ExecutionJournalEventName,
@@ -249,6 +255,32 @@ const EXECUTION_JOURNAL_EVENT_NAMES_SQL = EXECUTION_JOURNAL_EVENT_NAMES.map(
   (name) => `'${name}'`
 ).join(', ')
 
+/**
+ * One session's rows of the given kinds plus its `message/retracted` events (every effective-state
+ * reader needs the retractions), merged in entry_id order; bind `{ session }`. Written as
+ * `WHERE kind IN (...)` the planner walks the whole session by primary key and, under SQLCipher,
+ * decrypts every page the session touches. One range per kind on
+ * `idx_deepchat_tape_entries_session_kind` (retractions on the partial event-name index) loads only
+ * the pages that hold the requested rows, and SQLite merges the ordered ranges without a sort. On a
+ * 10k-entry encrypted session this halves the cold read of the effective-view inputs. The ranges
+ * are disjoint because `EffectiveInputKind` cannot name `event`; the kind lists are the same
+ * constants the JS predicates test.
+ */
+function effectiveInputRowsSql(kinds: readonly EffectiveInputKind[]): string {
+  const ranges = [
+    ...kinds.map(
+      (kind) =>
+        `SELECT * FROM deepchat_tape_entries WHERE session_id = $session AND kind = '${kind}'`
+    ),
+    `SELECT * FROM deepchat_tape_entries
+     WHERE session_id = $session AND kind = 'event' AND name = '${TAPE_MESSAGE_RETRACTED_EVENT_NAME}'`
+  ]
+  return `SELECT * FROM (${ranges.join(' UNION ALL ')}) ORDER BY entry_id ASC`
+}
+
+const EFFECTIVE_VIEW_INPUT_ROWS_SQL = effectiveInputRowsSql(EFFECTIVE_VIEW_INPUT_KINDS)
+const EFFECTIVE_MESSAGE_INPUT_ROWS_SQL = effectiveInputRowsSql(EFFECTIVE_MESSAGE_INPUT_KINDS)
+
 export const UNTERMINATED_EXECUTION_JOURNAL_EVENTS_SQL = `
   WITH unterminated_runs AS (
     SELECT DISTINCT started.session_id, started.source_id AS run_id
@@ -1201,20 +1233,16 @@ export class DeepChatTapeEntriesTable
       .all(sessionId) as DeepChatTapeEntryRow[]
   }
 
-  /** SQL mirror of `isEffectiveViewInputRow`; skips the bulky rows the effective view ignores. */
   getEffectiveViewInputRows(sessionId: string): DeepChatTapeEntryRow[] {
     return this.db
-      .prepare(
-        `SELECT *
-         FROM deepchat_tape_entries
-         WHERE session_id = ?
-           AND (
-             kind IN ('message', 'tool_call', 'tool_result', 'anchor')
-             OR (kind = 'event' AND name = 'message/retracted')
-           )
-         ORDER BY entry_id ASC`
-      )
-      .all(sessionId) as DeepChatTapeEntryRow[]
+      .prepare(EFFECTIVE_VIEW_INPUT_ROWS_SQL)
+      .all({ session: sessionId }) as DeepChatTapeEntryRow[]
+  }
+
+  getEffectiveMessageInputRows(sessionId: string): DeepChatTapeEntryRow[] {
+    return this.db
+      .prepare(EFFECTIVE_MESSAGE_INPUT_ROWS_SQL)
+      .all({ session: sessionId }) as DeepChatTapeEntryRow[]
   }
 
   getByEntryIds(sessionId: string, entryIds: readonly number[]): DeepChatTapeEntryRow[] {
diff --git a/src/main/tape/ports/storage.ts b/src/main/tape/ports/storage.ts
index beb446916..4b837f89b 100644
--- a/src/main/tape/ports/storage.ts
+++ b/src/main/tape/ports/storage.ts
@@ -89,6 +89,8 @@ export interface TapeEntryStore {
   getBySessionExcludingContext(sessionId: string): DeepChatTapeEntryRow[]
   /** Rows selected by `isEffectiveViewInputRow`, ordered by entry_id. */
   getEffectiveViewInputRows(sessionId: string): DeepChatTapeEntryRow[]
+  /** Rows selected by `isEffectiveMessageInputRow`, ordered by entry_id. */
+  getEffectiveMessageInputRows(sessionId: string): DeepChatTapeEntryRow[]
   getByEntryIds(sessionId: string, entryIds: readonly number[]): DeepChatTapeEntryRow[]
   getMessageSourceEntries(sessionId: string, messageId: string): DeepChatTapeEntryRow[]
   getLatestViewManifestEvent(sessionId: string): DeepChatTapeEntryRow | undefined
diff --git a/test/main/agent/acp/compatibility/adapters.test.ts b/test/main/agent/acp/compatibility/adapters.test.ts
index aeee81511..542751f0d 100644
--- a/test/main/agent/acp/compatibility/adapters.test.ts
+++ b/test/main/agent/acp/compatibility/adapters.test.ts
@@ -8,7 +8,10 @@ import {
 } from '@/agent/acp/compatibility/adapters'
 import { SessionTranscript } from '@/session/data/transcript'
 import { SessionTape } from '@/tape/application/sessionTape'
-import { isEffectiveViewInputRow } from '@/tape/domain/effectiveSemantics'
+import {
+  isEffectiveMessageInputRow,
+  isEffectiveViewInputRow
+} from '@/tape/domain/effectiveSemantics'
 import type { MainDatabase } from '@/data/mainDatabase'
 
 const publishDeepchatEvent = vi.fn()
@@ -188,6 +191,9 @@ function createProjectionHarness() {
       ),
       getEffectiveViewInputRows: vi.fn((sessionId: string) =>
         tapeRows.filter((row) => row.session_id === sessionId && isEffectiveViewInputRow(row))
+      ),
+      getEffectiveMessageInputRows: vi.fn((sessionId: string) =>
+        tapeRows.filter((row) => row.session_id === sessionId && isEffectiveMessageInputRow(row))
       )
     }
   } as unknown as MainDatabase
diff --git a/test/main/agent/deepchat/harness/deepChatAgentHarness.test.ts b/test/main/agent/deepchat/harness/deepChatAgentHarness.test.ts
index aebbb1857..154092449 100644
--- a/test/main/agent/deepchat/harness/deepChatAgentHarness.test.ts
+++ b/test/main/agent/deepchat/harness/deepChatAgentHarness.test.ts
@@ -31,7 +31,10 @@ import {
   getUsableContextLength
 } from '@/agent/deepchat/runtime/contextBudget'
 import { appendMessageRecordToTape } from '@/tape/application/factPersistence'
-import { isEffectiveViewInputRow } from '@/tape/domain/effectiveSemantics'
+import {
+  isEffectiveMessageInputRow,
+  isEffectiveViewInputRow
+} from '@/tape/domain/effectiveSemantics'
 import { resolveInterleavedReasoningConfig } from '@/agent/deepchat/runtime/generationSettings'
 import { toAcpRemoteSessionId, toAppSessionId } from '@/agent/shared/agentSessionIds'
 import { createLoopRun, type LoopRunRequestToolSurfaceBinding } from '@/agent/deepchat/loop/loopRun'
@@ -563,6 +566,11 @@ function createMockSqlitePresenter() {
           (entry) => entry.session_id === sessionId && isEffectiveViewInputRow(entry)
         )
       ),
+      getEffectiveMessageInputRows: vi.fn((sessionId: string) =>
+        tapeEntries.filter(
+          (entry) => entry.session_id === sessionId && isEffectiveMessageInputRow(entry)
+        )
+      ),
       getByEntryIds: vi.fn((sessionId: string, entryIds: readonly number[]) => {
         const selected = new Set(entryIds)
         return tapeEntries.filter(
diff --git a/test/main/session/data/tables/deepchatTapeEntriesTable.test.ts b/test/main/session/data/tables/deepchatTapeEntriesTable.test.ts
index 04be38ba7..3440a2232 100644
--- a/test/main/session/data/tables/deepchatTapeEntriesTable.test.ts
+++ b/test/main/session/data/tables/deepchatTapeEntriesTable.test.ts
@@ -4,7 +4,10 @@ import {
   TOOL_SURFACE_TAPE_EVENT_NAMES
 } from '@/tape/domain/toolSurfaceFacts'
 import { buildTapeProviderAttemptEvent } from '@/tape/domain/providerAttempt'
-import { isEffectiveViewInputRow } from '@/tape/domain/effectiveSemantics'
+import {
+  isEffectiveMessageInputRow,
+  isEffectiveViewInputRow
+} from '@/tape/domain/effectiveSemantics'
 import { TapeProviderAttemptService } from '@/tape/application/providerAttemptService'
 
 const sqliteModule = await import('better-sqlite3-multiple-ciphers').catch(() => null)
@@ -815,6 +818,11 @@ describeIfSqlite('DeepChatTapeEntriesTable', () => {
     expect(effective.map((row) => row.entry_id)).toEqual([2, 3, 4, 5, 7])
     expect(effective).toEqual(table.getBySession('s1').filter(isEffectiveViewInputRow))
 
+    const messages = table.getEffectiveMessageInputRows('s1')
+
+    expect(messages.map((row) => row.entry_id)).toEqual([2, 5])
+    expect(messages).toEqual(table.getBySession('s1').filter(isEffectiveMessageInputRow))
+
     db.close()
   })
 })
diff --git a/test/main/session/data/tapeFacts.test.ts b/test/main/session/data/tapeFacts.test.ts
index 157cec7d7..56e1c9b15 100644
--- a/test/main/session/data/tapeFacts.test.ts
+++ b/test/main/session/data/tapeFacts.test.ts
@@ -11,7 +11,11 @@ import {
 } from '@/tape/domain/effectiveView'
 import { TAPE_COMPACTION_MODEL_CALL_EVENT_NAME } from '@/tape/domain/compactionUsage'
 import { TOOL_SURFACE_TAPE_EVENT_NAMES } from '@/tape/domain/toolSurfaceFacts'
-import { messageRecordHasFinalToolUse, tapeToolRank } from '@/tape/domain/effectiveSemantics'
+import {
+  isEffectiveMessageInputRow,
+  messageRecordHasFinalToolUse,
+  tapeToolRank
+} from '@/tape/domain/effectiveSemantics'
 import type { DeepChatTapeEntryRow } from '@/tape/domain/entry'
 
 function createTable() {
@@ -378,4 +382,43 @@ describe('buildEffectiveTapeView messageEntries (lineage pairing)', () => {
     const ids = buildEffectiveTapeView(table.rows).messageEntries.map((entry) => entry.record.id)
     expect(ids).toEqual(['u1'])
   })
+
+  it('derives messageRecords from message and retraction rows alone', () => {
+    const table = createTable()
+    table.append({ sessionId: 's1', kind: 'anchor', name: 'session/start', payload: {} })
+    appendMessageRecordToTape(table as any, userRecord('u1', 1, 'first'), 'live')
+    appendMessageRecordToTape(
+      table as any,
+      assistantRecord([toolCallBlock('success', 'tc1', 'result')], { status: 'sent' }),
+      'live'
+    )
+    appendMessageRecordToTape(table as any, userRecord('u2', 3, 'retract me'), 'live')
+    table.append({
+      sessionId: 's1',
+      kind: 'event',
+      name: 'message/retracted',
+      payload: { data: { messageId: 'u2' } }
+    })
+    appendMessageRecordToTape(
+      table as any,
+      userRecord('u3', 4, 'pending', { status: 'pending' }),
+      'live'
+    )
+    table.append({ sessionId: 's1', kind: 'event', name: 'view/assembled', payload: {} })
+    expect(new Set(table.rows.map((row) => row.kind))).toEqual(
+      new Set(['anchor', 'message', 'tool_call', 'tool_result', 'event'])
+    )
+
+    for (const includePending of [true, false]) {
+      const full = buildEffectiveTapeView(table.rows, { includePending })
+      const messagesOnly = buildEffectiveTapeView(table.rows.filter(isEffectiveMessageInputRow), {
+        includePending
+      })
+      expect(messagesOnly.messageRecords).toEqual(full.messageRecords)
+      expect(messagesOnly.messageEntries).toEqual(full.messageEntries)
+    }
+    expect(
+      buildEffectiveTapeView(table.rows, { includePending: true }).messageRecords.map((r) => r.id)
+    ).toEqual(['u1', 'a1', 'u3'])
+  })
 })
diff --git a/test/main/session/data/tapeTableMockContract.test.ts b/test/main/session/data/tapeTableMockContract.test.ts
index b39b2b175..021ecced0 100644
--- a/test/main/session/data/tapeTableMockContract.test.ts
+++ b/test/main/session/data/tapeTableMockContract.test.ts
@@ -168,7 +168,7 @@ function seedConversation(store: Store) {
     sessionId: SESSION,
     name: 'message/retracted',
     source: { type: 'message', id: 'm2', seq: 0 },
-    data: { reason: 'user_delete' },
+    data: { messageId: 'm2', reason: 'user_delete' },
     createdAt: 150
   })
   store.appendAnchor({
@@ -258,6 +258,82 @@ function seedConversation(store: Store) {
   })
 }
 
+const REVISION_SESSION = 's3'
+
+/**
+ * One assistant message written three times: a sent revision that is retracted, a sent revision
+ * at a shifted orderSeq that supersedes it, and a pending revision that must not. Its tool rows
+ * use the production payload shape (`messageId`/`orderSeq` in the payload, `toolCall` as an
+ * object for the first call and as legacy JSON text for the second) so the join, the orderSeq
+ * rewrite and both `toolCall` encodings are compared between the SQL and JS effective views.
+ */
+function seedRevisedAssistant(store: Store) {
+  bootstrap(store, REVISION_SESSION, '00000000-0000-4000-8000-000000000003')
+  const assistant = (orderSeq: number, text: string, status: 'sent' | 'pending', seq: number) =>
+    store.append({
+      sessionId: REVISION_SESSION,
+      kind: 'message',
+      name: 'message/assistant',
+      source: { type: 'message', id: 'a1', seq },
+      payload: {
+        record: createRecord({
+          id: 'a1',
+          sessionId: REVISION_SESSION,
+          role: 'assistant',
+          orderSeq,
+          status,
+          content: JSON.stringify([{ type: 'content', content: text }])
+        })
+      },
+      meta: { status },
+      createdAt: 100 + seq
+    })
+  const toolCall = (toolCallId: string, orderSeq: number, toolCall: unknown, createdAt: number) =>
+    store.append({
+      sessionId: REVISION_SESSION,
+      kind: 'tool_call',
+      name: 'read_file',
+      source: { type: 'tool_call', id: `a1:${toolCallId}`, seq: 0 },
+      payload: { messageId: 'a1', orderSeq, toolCall },
+      meta: { status: 'success' },
+      createdAt
+    })
+  const toolResult = (toolCallId: string, orderSeq: number, response: string, createdAt: number) =>
+    store.append({
+      sessionId: REVISION_SESSION,
+      kind: 'tool_result',
+      name: 'read_file',
+      source: { type: 'tool_result', id: `a1:${toolCallId}`, seq: 0 },
+      payload: { messageId: 'a1', orderSeq, toolCallId, response },
+      meta: { status: 'success' },
+      createdAt
+    })
+
+  assistant(2, 'draft one', 'sent', 0) // entry 2
+  toolCall('tc1', 2, { id: 'tc1', name: 'read_file' }, 110) // entry 3
+  toolResult('tc1', 2, 'needle one', 111) // entry 4
+  store.appendEvent({
+    sessionId: REVISION_SESSION,
+    name: 'message/retracted',
+    source: { type: 'message', id: 'a1', seq: 0 },
+    data: { messageId: 'a1', reason: 'edit' },
+    createdAt: 120
+  }) // entry 5
+  store.append({
+    sessionId: REVISION_SESSION,
+    kind: 'message',
+    name: 'message/user',
+    source: { type: 'message', id: 'u1', seq: 0 },
+    payload: { record: createRecord({ id: 'u1', sessionId: REVISION_SESSION, orderSeq: 1 }) },
+    meta: { status: 'sent' },
+    createdAt: 125
+  }) // entry 6
+  assistant(4, 'draft two', 'sent', 1) // entry 7, orderSeq shifted from 2 to 4
+  toolCall('tc2', 4, JSON.stringify({ id: 'tc2', name: 'read_file' }), 130) // entry 8
+  toolResult('tc2', 4, 'needle two', 131) // entry 9
+  assistant(4, 'draft three', 'pending', 2) // entry 10
+}
+
 describe('Tape table mock contract', () => {
   itIfSqlite('appends rows with the same ids, provenance keys and idempotency', () => {
     const stores = openStores()
@@ -442,6 +518,7 @@ describe('Tape table mock contract', () => {
         messageSourcesMissing: (store) => store.getMessageSourceEntries(SESSION, 'nope'),
         excludingContext: (store) => store.getBySessionExcludingContext(SESSION),
         effectiveViewInputs: (store) => store.getEffectiveViewInputRows(SESSION),
+        effectiveMessageInputs: (store) => store.getEffectiveMessageInputRows(SESSION),
         lineage: (store) => store.getSubagentLineageEvents(SESSION),
         effectiveSearchAtHeads: (store) =>
           store.searchEffectiveSourcesAtHeads(
@@ -459,13 +536,87 @@ describe('Tape table mock contract', () => {
             [2],
             { before: 1, after: 3, limit: 10 }
           ),
-        effectiveContextRetracted: (store) =>
+        // The retracted m2 (entry 8) neither anchors a window nor appears in its neighbour's.
+        retractedIsNotAnAnchor: (store) =>
           store.getEffectiveContextRowsAtHead(
             { sessionId: SESSION, maxEntryId: store.getMaxEntryId(SESSION) },
             [8],
             { before: 0, after: 0, limit: 10 }
+          ),
+        retractedLeavesTheWindow: (store) =>
+          store.getEffectiveContextRowsAtHead(
+            { sessionId: SESSION, maxEntryId: store.getMaxEntryId(SESSION) },
+            [5],
+            { before: 0, after: 2, limit: 10 }
           )
       })
+
+      const afterA1 = stores.real
+        .getEffectiveContextRowsAtHead(
+          { sessionId: SESSION, maxEntryId: stores.real.getMaxEntryId(SESSION) },
+          [5],
+          { before: 0, after: 2, limit: 10 }
+        )
+        .map((row) => row.entry_id)
+        .sort((left, right) => left - right)
+      expect(afterA1).toEqual([5, 10, 11])
+    } finally {
+      stores.close()
+    }
+  })
+
+  itIfSqlite('resolves revisions, retractions and tool joins identically', () => {
+    const stores = openStores()
+    try {
+      for (const store of [stores.real, stores.mock]) seedRevisedAssistant(store)
+
+      const head = (store: Store) => ({
+        sessionId: REVISION_SESSION,
+        maxEntryId: store.getMaxEntryId(REVISION_SESSION)
+      })
+      expectParity(stores, {
+        // The surviving a1 revision (entry 7) with every tool row joined onto it, each tool row's
+        // stored orderSeq rewritten to the revision's orderSeq.
+        effectiveWindow: (store) =>
+          store.getEffectiveContextRowsAtHead(head(store), [7], { before: 5, after: 5, limit: 20 }),
+        // The retracted first revision is not an effective row, so nothing anchors the window.
+        retractedRevision: (store) =>
+          store.getEffectiveContextRowsAtHead(head(store), [2], { before: 1, after: 1, limit: 20 }),
+        // Before the retraction the first revision and its object-form tool call are effective.
+        firstRevisionWindow: (store) =>
+          store.getEffectiveContextRowsAtHead({ sessionId: REVISION_SESSION, maxEntryId: 4 }, [2], {
+            before: 1,
+            after: 3,
+            limit: 20
+          }),
+        // Tool results of both revisions match; the pending third revision contributes nothing.
+        toolResultSearch: (store) => store.searchEffectiveSourcesAtHeads([head(store)], 'needle'),
+        pendingSearch: (store) => store.searchEffectiveSourcesAtHeads([head(store)], 'draft three')
+      })
+
+      // The reader lists requested rows before their neighbours; sort to assert the window's content.
+      const window = stores.real
+        .getEffectiveContextRowsAtHead(head(stores.real), [7], { before: 5, after: 5, limit: 20 })
+        .sort((left, right) => left.entry_id - right.entry_id)
+      expect(window.map((row) => [row.entry_id, row.kind])).toEqual([
+        [1, 'anchor'],
+        [3, 'tool_call'],
+        [4, 'tool_result'],
+        [6, 'message'],
+        [7, 'message'],
+        [8, 'tool_call'],
+        [9, 'tool_result']
+      ])
+      expect(
+        window
+          .filter((row) => row.kind === 'tool_call' || row.kind === 'tool_result')
+          .map((row) => JSON.parse(row.payload_json).orderSeq)
+      ).toEqual([4, 4, 4, 4])
+      expect(
+        stores.real
+          .searchEffectiveSourcesAtHeads([head(stores.real)], 'needle')
+          .map((row) => row.entry_id)
+      ).toEqual([9, 4])
     } finally {
       stores.close()
     }
diff --git a/test/main/session/data/tapeTestHarness.ts b/test/main/session/data/tapeTestHarness.ts
index 21a886e52..6cf78790a 100644
--- a/test/main/session/data/tapeTestHarness.ts
+++ b/test/main/session/data/tapeTestHarness.ts
@@ -20,7 +20,10 @@ import {
   DeepChatTapeEntriesTable,
   MAX_TAPE_SEARCH_TOKEN_CLAUSES
 } from '@/tape/infrastructure/sqlite/tapeEntryStore'
-import { isEffectiveViewInputRow } from '@/tape/domain/effectiveSemantics'
+import {
+  isEffectiveMessageInputRow,
+  isEffectiveViewInputRow
+} from '@/tape/domain/effectiveSemantics'
 import { SUMMARY_ANCHOR_NAMES } from '@/tape/domain/entry'
 import { EXECUTION_JOURNAL_EVENT_NAMES } from '@/tape/domain/executionJournal'
 import {
@@ -440,6 +443,9 @@ function createTapeTableMock() {
     getEffectiveViewInputRows: vi.fn((sessionId: string) =>
       entries.filter((entry) => entry.session_id === sessionId && isEffectiveViewInputRow(entry))
     ),
+    getEffectiveMessageInputRows: vi.fn((sessionId: string) =>
+      entries.filter((entry) => entry.session_id === sessionId && isEffectiveMessageInputRow(entry))
+    ),
     getByEntryIds: vi.fn((sessionId: string, entryIds: readonly number[]) => {
       const selected = new Set(entryIds)
       return entries.filter(
diff --git a/test/main/session/runtimeIntegration.test.ts b/test/main/session/runtimeIntegration.test.ts
index 7b21d50b7..b7c9aff41 100644
--- a/test/main/session/runtimeIntegration.test.ts
+++ b/test/main/session/runtimeIntegration.test.ts
@@ -14,7 +14,10 @@ import { createSessionQueryFixture } from './queryFixture'
 import { createSessionFixture } from './sessionFixture'
 import { createSessionData, createSessionDataFromDatabase } from '@/session/data'
 import { SessionTranscriptMutations } from '@/session/transcriptMutations'
-import { isEffectiveViewInputRow } from '@/tape/domain/effectiveSemantics'
+import {
+  isEffectiveMessageInputRow,
+  isEffectiveViewInputRow
+} from '@/tape/domain/effectiveSemantics'
 import { createPassthroughModelRequestPolicy } from '@shared/modelRequestPolicy'
 import { POSIX_COMMAND_SHELL } from '../../helpers/commandShell'
 
@@ -179,6 +182,11 @@ function createMockSqlitePresenter() {
         (entry) => entry.session_id === sessionId && isEffectiveViewInputRow(entry)
       )
     ),
+    getEffectiveMessageInputRows: vi.fn((sessionId: string) =>
+      tapeEntries.filter(
+        (entry) => entry.session_id === sessionId && isEffectiveMessageInputRow(entry)
+      )
+    ),
     getByEntryIds: vi.fn((sessionId: string, entryIds: readonly number[]) => {
       const requestedIds = new Set(entryIds)
       return tapeEntries.filter(
diff --git a/test/main/tape/executionJournal.test.ts b/test/main/tape/executionJournal.test.ts
index ddaa96ab3..b5d87d90f 100644
--- a/test/main/tape/executionJournal.test.ts
+++ b/test/main/tape/executionJournal.test.ts
@@ -848,6 +848,32 @@ describe('Execution Journal domain and strict persistence', () => {
     ])
   })
 
+  it('canonicalises the Run ID and only accepts UUID versions 1-8', () => {
+    const { table, entries } = createTapeTableMock()
+    const service = createTapeService(table)
+
+    // Hex letters, so the upper-case spelling really differs from the canonical one.
+    const canonical = 'abcdef01-2345-4678-8abc-def012345678'
+    const upperCase = canonical.toUpperCase()
+    expect(upperCase).not.toBe(canonical)
+
+    const first = commitStarted(service, upperCase)
+    const replay = commitStarted(service, canonical)
+    expect(first.created).toBe(true)
+    expect(replay).toEqual({ ...first, created: false })
+    expect(JSON.parse(entries[entries.length - 1].payload_json).data.runId).toBe(canonical)
+    expect(entries[entries.length - 1].provenance_key).toBe(
+      buildExecutionRunProvenanceKey(canonical, 'started')
+    )
+
+    for (const version of ['0', '9', 'f']) {
+      expect(() => commitStarted(service, `55555555-5555-${version}555-8555-555555555555`)).toThrow(
+        /runId must be a UUID/
+      )
+    }
+    expect(entries.filter((entry) => entry.name?.startsWith('execution/'))).toHaveLength(1)
+  })
+
   it('rejects non-JSON arguments and invalid timestamps before append', () => {
     const { table, entries } = createTapeTableMock()
     const service = createTapeService(table)