Refresh public links and include development screenshots

README.md

@@ -87,14 +87,21 @@ season enrollment, and instability controls. The client setting
 An operator can inspect Ages and instability with `/rivencraft age` and find
 libraries with `/rivencraft library nearest`. The creative-only Link Modifier
 can edit link properties and retire an Age; use it carefully and keep backups.
+Binder status messages are off by default. An OP can run
+`/rivencraft binder messages enable` or `/rivencraft binder messages disable`
+to control them; only OPs see the diagnostics even when enabled.
 
 ## Project and development
 
 This repository is the development source. See the [current implementation](docs/CURRENT_IMPLEMENTATION.md),
 [milestone summaries](docs/MILESTONES.md), [technical document index](docs/README.md),
-and [issues](https://truenas-scale.tail180fb1.ts.net:8443/dnorberg/rivencraft/issues).
-Milestone 7 is in progress; its [regression matrix](docs/MILESTONE_7_REGRESSION.md)
-distinguishes automated checks from manual checks and known limitations.
+and [issues](https://git.paddedcell.org/dnorberg/rivencraft/issues).
+Help build the [Rivencraft wiki](https://git.paddedcell.org/dnorberg/rivencraft/wiki)
+with guides for Ages, pages, and crafting, or open an issue with documentation
+suggestions and corrections.
+Milestone 7 is complete in 1.0.0.2. Its [acceptance record](docs/MILESTONE_7_ACCEPTANCE.md)
+and [regression matrix](docs/MILESTONE_7_REGRESSION.md) distinguish automated
+checks from manual evidence and known limitations.
 
 ```sh
 ./gradlew build

docs/CURRENT_IMPLEMENTATION.md

@@ -1,6 +1,6 @@
 # Current implementation (Milestone 7 development)
 
-This is the maintained technical overview of Rivencraft as of the 0.6.11.0
+This is the maintained technical overview of Rivencraft as of the 1.0.0.2
 slice. It describes implemented behavior, not every behavior in Mystcraft
 Legacy. [The README](../README.md) is the player introduction;
 [milestone summaries](MILESTONES.md) explain how the implementation arrived
@@ -41,9 +41,11 @@ and [Age administration](AGES.md).
   terrain starts from exposed surfaces. If no safe arrival site exists, the
   Age-creation path can construct a non-dropping Crystal Platform at Y=63.
 - The server catalog accepts typed data-pack symbols. The Binder preserves
-  written order and diagnoses conflicts. Symbol Pages are composed at runtime
-  from Legacy glyph assets; number pages 0–24 set color strength and, when
-  immediately before a Length, Angle, or Phase modifier, their numeric value.
+  written order and diagnoses conflicts. Its status readout is off by default;
+  `/rivencraft binder messages enable` makes it visible only to OPs. Symbol
+  Pages are composed at runtime from Legacy glyph assets. Number pages 0–24
+  set color strength or, immediately before a Length, Angle, Phase, or Size
+  modifier, its numeric value.
   Celestial pages can create multiple suns/moons with independent color, size,
   angle, period, phase, and direction; authored eclipses affect light.
 - The Writing Desk stores tabs and copies known Symbol Pages with paper and
@@ -92,5 +94,5 @@ This is not an exact port of every Legacy generator, page, hazard, or client
 renderer. Modern safety budgets and NeoForge's dimension/biome APIs require
 adaptations. The [Milestone 7 regression matrix](MILESTONE_7_REGRESSION.md)
 separates tested behavior from unverified multiplayer/restart/optional-mod
-combinations. Issue [#84](https://truenas-scale.tail180fb1.ts.net:8443/dnorberg/rivencraft/issues/84)
-is the final Milestone 7 acceptance and release gate.
+combinations. The [Milestone 7 acceptance record](MILESTONE_7_ACCEPTANCE.md)
+records release evidence and remaining validation limits.

docs/MILESTONES.md

@@ -54,12 +54,13 @@ adaptations. See [M6 acceptance](MILESTONE_6_ACCEPTANCE.md),
 [Legacy instability audit](LEGACY_INSTABILITY_AUDIT.md), and
 [runtime policy](INSTABILITY_RUNTIME.md).
 
-## 7 — Structures and polish (in progress)
+## 7 — Structures and polish (complete in 1.0.0.2)
 
 Added Legacy-layout Age libraries, page-bearing stands, crystal portals and
 receptacles, the handheld dropped-book entity, data-driven recipes,
 advancements, asset/audio polish, optional Ruins, compatibility updates, and
-expanded sky/glyph pages. Issue #83 covers regression, migration, and document
-consolidation; issue #84 is the final milestone acceptance gate. See the
-[M7 Legacy audit](LEGACY_M7_AUDIT.md), [M7 regression matrix](MILESTONE_7_REGRESSION.md),
-and [M7 compatibility review](MILESTONE_7_COMPATIBILITY_REVIEW.md).
+expanded sky/glyph pages. Issue #83 covered regression, migration, and document
+consolidation; issue #84 records the final milestone acceptance. See the
+[M7 acceptance](MILESTONE_7_ACCEPTANCE.md), [M7 Legacy audit](LEGACY_M7_AUDIT.md),
+[M7 regression matrix](MILESTONE_7_REGRESSION.md), and
+[M7 compatibility review](MILESTONE_7_COMPATIBILITY_REVIEW.md).

docs/MILESTONE_7_ACCEPTANCE.md

@@ -0,0 +1,72 @@
+# Milestone 7 acceptance — 1.0.0.2
+
+Milestone 7 is complete for the supported NeoForge 1.21.1 feature set. This is
+not a claim of total Mystcraft Legacy parity or exhaustive optional-mod
+certification. The [current implementation](CURRENT_IMPLEMENTATION.md) is the
+up-to-date behavior summary; the [regression matrix](MILESTONE_7_REGRESSION.md)
+separates automated evidence from manual scenarios.
+
+## Scope and issue gate
+
+The Gitea audit for issue #84 found no other open issues. Required existing
+#14 (cave terrain), #43 (glyph numbers), #44 (sky), and #60 (old-save policy)
+were closed. M7 implementation and review issues #75–#83, #85–#90, and
+later additions #91–#94 were closed before this acceptance. No required
+issue was silently deferred.
+
+| Legacy concept | Rivencraft implementation or deliberate difference |
+| --- | --- |
+| Cave terrain and writing | Cave terrain uses its cave/Nether biome set and a modern Y=64-start spawn search. Existing non-cave terrain still supports caves as features. See [Age profiles](AGE_PROFILES.md) and [grammar](WRITING_GRAMMAR.md). |
+| Libraries | The recognizable Legacy small-library layout and sparse candidate spacing are ported as a structure template with a chest and up to five page-bearing Book Stands. It generates only in Ages and only on suitable surfaces; player-selectable Legacy or Age-only loot is supported. See [Legacy M7 audit](LEGACY_M7_AUDIT.md). |
+| Crystal portal and Receptacle | Connected Crystal Blocks support vertical and horizontal portals. The held book stays in the Receptacle; removing it removes the surface. Rivencraft validates loaded bounds and block protection, saves owner pointers, and uses book-travel rules. Optional Immersive Portals supplies a live destination view, with an animated fallback while unavailable. |
+| Handheld Linking/Descriptive Books | The used book remains behind as a rendered book entity at the origin. The exact Legacy entity pickup rule is not copied: modern contact pickup is used. Return Links default to disabled but remain configurable. |
+| Recipes and discovery | JSON crafting recipes and recipe-book unlocks cover the supported writing/crystal progression. Optional JEI covers the Binder, Writing Desk, and Ink Mixer; a Lectern conversion has no JEI guide. Blank Pages are not craftable. Optional Create/Ponder teaches portal construction. See [JEI review](MILESTONE_7_JEI_REVIEW.md). |
+| Models, sounds, and advancements | Legacy-sourced assets are credited in [asset provenance](ASSET_PROVENANCE.md); 1.21.1-compatible models and renderer adaptations are documented in the [visual audit](MILESTONE_7_VISUAL_AUDIT.md). Server-owned advancements cover book, writing, Age, and portal progress; the unimplemented Quinn equivalent is explicitly omitted in [advancement notes](MILESTONE_7_ADVANCEMENTS.md). |
+| Numbers, sky, and extra items | Base-25 number glyphs, celestial modifiers and eclipses, Symbol Portfolios, the OP-only Link Modifier, and optional Ruins pages were follow-up additions. Legacy page semantics are adapted to the modern authoring plan rather than a binary copy of 1.12.2 worldgen. |
+
+## Compatibility and migration
+
+NeoForge **21.1.264** is the minimum 21.1 build. A player passed the
+singleplayer client with the optional stack, then a local dedicated server
+including Immersive Portals, before the minimum was raised. See the
+[compatibility decision](MILESTONE_7_COMPATIBILITY_REVIEW.md). JEI
+19.69.0.457 and Serene Seasons 10.1.0.9 received their own player checks;
+Create/Ponder, Immersive Portals, TerraBlender/biome add-ons, Serene Seasons,
+JEI, and Ruins remain optional. Ecliptic Seasons is deliberately not
+integrated: its 1.21.1 public API does not support the required live Age
+registration and per-Age calendar control. Missing optional mods must not
+prevent the core mod from loading.
+
+Known older writing/book, Age-plan, and workstation formats have explicit
+migration or stable-default handling. An Age registry and its dimension
+folders must be backed up together. Removed mods, missing custom registry
+objects, and arbitrary prerelease saves are **not** guaranteed to load.
+Retiring an Age through the creative Link Modifier archives its data and
+invalidates its UUID; that intentional destructive operation is not a
+migration. See the [old-save boundary](MILESTONE_7_REGRESSION.md#old-save-boundary-60).
+
+## Release validation and limits
+
+The 0.6.11.0 regression candidate passed `./gradlew --offline build` and
+fresh-world GameTest runs: core **91/91**, generation **129/129**, and
+environment **103/103**. The player reported an in-game pass for that
+candidate. The 1.0.0.1 release candidate additionally allows Number Pages to
+set Celestial Size. The 1.0.0.2 release makes Binder status diagnostics an
+OP-only, default-off world setting. Its offline build and core GameTests
+passed (93/93), and the player reported an in-game pass. The
+preceding 1.0.0.0 candidate passed core and generation GameTests. Its
+environment archive stalled in the first 50-test batch, repeatedly printing
+its field without completing; it was stopped and is **not** counted as a
+1.0.0.0–1.0.0.2 pass. The previous 0.6.11.0 run of that same suite passed 103/103.
+The focused sky, season, and number-page in-game checks in the regression
+matrix remain useful regression checks, not claimed full-matrix passes. The
+Gitea release changelog records the tested JAR and verified SHA-256.
+
+These results do not prove every two-player race, full restart, migration
+from every development world, or optional-mod combination. The specific
+manual matrix remains in [M7 regression](MILESTONE_7_REGRESSION.md); those
+broader combinations are known validation limits, not claimed passes. Modern
+chunk and tick budgets, safer portal validation, 1.21.1 world-height and
+biome APIs, and the dynamic-dimension backend are deliberate deviations from
+Legacy. A complete Legacy worldgen or link-property port is outside this
+milestone.

docs/MILESTONE_7_REGRESSION.md

@@ -1,7 +1,7 @@
 # Milestone 7 regression and migration matrix (issue #83)
 
-This is a **working** acceptance record for the 0.6.11.0 candidate, not the
-Milestone 7 completion sign-off. Issue #84 owns the final gate. A passing
+This is the dated regression record for the 0.6.11.0 candidate. The
+[Milestone 7 acceptance](MILESTONE_7_ACCEPTANCE.md) owns the final sign-off. A passing
 GameTest is server-side evidence; it is not proof of client rendering,
 multiplayer timing, or every optional-mod combination.
 
@@ -11,7 +11,7 @@ multiplayer timing, or every optional-mod combination.
 | --- | --- | --- |
 | Dedicated server, core linking, book/Age identity, old writing and workstation formats | `./gradlew --offline runGameTestServer`; includes `CoreGameTests`, `AgePersistenceGameTests`, `CrystalPortalGameTests`, M7 crafting/advancement checks | 91/91 required GameTests passed on NeoForge 21.1.264; clean shutdown and fresh-world removal. |
 | Deterministic structures and terrain | `./gradlew --offline runGameTestServer -ParchivedGameTestSuites=generation`; includes library template/spacing/loot/stand checks, cave profiles, vanilla structures, crystal formations, fissures | 129/129 passed after correcting one village test to assert its own contribution rather than a seed-dependent total; fresh-world removal. |
-| Sky, glyph numbers, seasons, creative/JEI page feed | `./gradlew --offline runGameTestServer -ParchivedGameTestSuites=environment` | 103/103 passed on the current candidate, including issue #94's number-page check; fresh-world removal. |
+| Sky, glyph numbers, seasons, creative/JEI page feed | `./gradlew --offline runGameTestServer -ParchivedGameTestSuites=environment` | 103/103 passed on the 0.6.11.0 candidate, including issue #94's number-page check; fresh-world removal. |
 | Packaged models and data | `Milestone7ResourceGameTests.coreModelsResolveBundledTextures` in the core suite; parses critical block models, checks their Rivencraft texture references and the library NBT resource | Passed in the 91-test core run. This checks resource presence, not visual orientation or transparency. |
 | Recipe behavior | `Milestone7CraftingGameTests` and `LinkingBookRecipeGameTests` through the loaded Recipe Manager | Passed in the core run; confirms crystal and receptacle quantities, ink bucket return, no Blank Page crafting, and Linking Book ingredients. |
 | Portal state/save-load | `CrystalPortalGameTests` plus `AgePersistenceGameTests` in the core suite | Passed; covers activation/release, fallback orientation, horizontal/underside placement, uninterrupted surface, cooldown, retired Age and seed/plan identity. Full server restart remains manual. |
@@ -29,7 +29,14 @@ and deletes it after pass or fail. See [GameTest guidance](GAMETESTS.md).
 Do not retry a storage-stalled GameTest: stop it, remove that automated
 scenario, and give its exact steps to the player. No run in this issue has
 stalled so far. The older full-archive storage stall is historical and is not
-counted as a current pass.
+counted as a current pass. On the subsequent **1.0.0.0 release candidate**,
+the environment archive stalled during its first 50-test batch and was
+stopped. The 103/103 result above applies to 0.6.11.0 only, not to 1.0.0.0
+or the later 1.0.0.1–1.0.0.2 candidates. For the 1.0.0.2 manual handoff, create an Age
+with Number Pages immediately before Celestial Angle, Phase, and Size pages;
+confirm each affects the intended body rather than becoming a stray page. Also verify a
+fixed-season Age remains fixed across a restart while the Overworld remains
+independent. Do not rerun the stalled suite merely to obtain a green count.
 
 ## Old-save boundary (#60)
 
@@ -60,6 +67,7 @@ this candidate.
 | Optional renderers | With neither Create nor Immersive Portals, confirm Legacy fallback. With Create alone, confirm Ponder snapshots and portal guide. With Immersive Portals, confirm live view, Explore exit, sky/sound isolation, portal travel, and fallback while chunks load. With both, `AUTO` should choose Immersive Portals. |
 | Optional world/recipe mods | Test JEI guides/search, TerraBlender with a biome-producing addon (for example Biomes O' Plenty), Serene's six season modes plus Overworld independence/restart, and Ruins template selection/spawn weighting. Repeat startup without optional mods. |
 | Migration | Copy a backed-up older development world. Verify books and Notebooks retain their Age/page IDs, a desk and stand keep contents, old Ages load or provide a clear error, and removing a custom symbol retains its unresolved ID. Do not test by modifying the only copy. |
+| Binder diagnostics | As a non-OP, verify the Binder still creates books but shows no instability/seeded/status messages. As an OP, run `/rivencraft binder messages enable`, reopen the Binder, and verify those messages appear only for the OP. Disable them and restart the world; the setting should remain disabled. |
 
 Historical evidence: the player approved NeoForge 21.1.264 on singleplayer
 and a dedicated server with Immersive Portals; JEI 19.69.0.457 guides, Serene

docs/README.md

@@ -13,7 +13,7 @@ former behavior or loader version.
 | M4 | [Writing data](WRITING_DATA.md), [book presentation](DESCRIPTIVE_BOOK_PRESENTATION.md), [Ink Mixer audit](INK_MIXER_MODIFIER_AUDIT.md) |
 | M5 | [Acceptance](MILESTONE_5_ACCEPTANCE.md), [Legacy grammar audit](LEGACY_AGE_GRAMMAR_AUDIT.md), [writing grammar](WRITING_GRAMMAR.md), [symbol semantics](SYMBOL_SEMANTICS.md), [TerraBlender](TERRABLENDER_COMPATIBILITY.md), [Serene Seasons](SERENE_SEASONS_COMPATIBILITY.md) |
 | M6 | [Acceptance](MILESTONE_6_ACCEPTANCE.md), [regression](MILESTONE_6_REGRESSION.md), [Legacy audit](LEGACY_INSTABILITY_AUDIT.md), [score](INSTABILITY_SCORE.md), [live blocks](LIVE_BLOCK_INSTABILITY.md), [runtime](INSTABILITY_RUNTIME.md), [diagnostics](INSTABILITY_DIAGNOSTICS.md), [status effects](INSTABILITY_STATUS_EFFECTS.md), [decay](INSTABILITY_DECAY.md), [environmental hazards](INSTABILITY_ENVIRONMENTAL.md), [cloud platform](AGE_CLOUD_PLATFORM.md) |
-| M7 | [Regression and manual matrix](MILESTONE_7_REGRESSION.md), [Legacy audit](LEGACY_M7_AUDIT.md), [visual/audio](MILESTONE_7_VISUAL_AUDIT.md), [advancements](MILESTONE_7_ADVANCEMENTS.md), [JEI](MILESTONE_7_JEI_REVIEW.md), [Serene review](MILESTONE_7_SERENE_REVIEW.md), [compatibility](MILESTONE_7_COMPATIBILITY_REVIEW.md), [Ruins](RUINS_COMPATIBILITY.md) |
+| M7 | [Acceptance](MILESTONE_7_ACCEPTANCE.md), [regression and manual matrix](MILESTONE_7_REGRESSION.md), [Legacy audit](LEGACY_M7_AUDIT.md), [visual/audio](MILESTONE_7_VISUAL_AUDIT.md), [advancements](MILESTONE_7_ADVANCEMENTS.md), [JEI](MILESTONE_7_JEI_REVIEW.md), [Serene review](MILESTONE_7_SERENE_REVIEW.md), [compatibility](MILESTONE_7_COMPATIBILITY_REVIEW.md), [Ruins](RUINS_COMPATIBILITY.md) |
 
 [Asset provenance](ASSET_PROVENANCE.md) applies across milestones. Detailed
 audits are intentionally retained for source attribution and migration

docs/SYMBOL_SEMANTICS.md

@@ -35,6 +35,7 @@ The Writing Desk retains 88 collection tabs, numbered from zero as in Legacy. Le
 | `period_modifier` | JSON number in `[0, 2]`; zero is stopped time. An immediately preceding D'ni number page overrides it with digit × 0.08. |
 | `angle_modifier` | JSON number in `[0, 360)` degrees. An immediately preceding D'ni number page overrides it with digit × 15°, wrapping 360° to 0°. |
 | `phase_modifier` | JSON number in `[0, 360)` degrees; the compiler converts it to turns. An immediately preceding D'ni number page overrides it with digit × 15°, wrapping 360° to 0°. |
+| `size_modifier` | JSON scale in `[0.25, 3]`. An immediately preceding D'ni number page overrides it with a linear 0.25×–3× scale: digit 0 is 0.25× and digit 24 is 3×. Without a number, Small/Normal/Large remain 0.5×/1×/2×. |
 | `block` | Canonical namespaced material ID for a compatible following feature; registered full-collision blocks and source fluids receive generated Pages. |
 | `feature` | Canonical namespaced feature-effect ID; the compiler must recognize and validate it. This includes supported decorations and structures. |
 

gradle.properties

@@ -36,7 +36,7 @@ mod_name=Rivencraft
 # The license of the mod. Review your options at https://choosealicense.com/. All Rights Reserved is the default.
 mod_license=LGPL-3.0-or-later
 # The mod version. Rivencraft uses the x.y.z.b policy documented in README.md.
-mod_version=0.6.11.0
+mod_version=1.0.1.1
 immersive_portals_version=6.0.7
 terrablender_version=4.1.0.8
 serene_seasons_version_id=pHEgQQUE

src/main/java/net/dnorberg/rivencraft/book/AgeBiomeSelection.java

@@ -8,6 +8,7 @@ import java.util.Random;
 import java.util.Set;
 import net.dnorberg.rivencraft.Rivencraft;
 import net.dnorberg.rivencraft.compat.TerraBlenderBiomes;
+import net.dnorberg.rivencraft.writing.BiomeSymbolPages;
 import net.dnorberg.rivencraft.writing.SymbolSemantics;
 import net.dnorberg.rivencraft.writing.WritingGrammar;
 import net.minecraft.core.Holder;
@@ -34,6 +35,12 @@ public record AgeBiomeSelection(AgeTraits.BiomeDistribution distribution, List<R
 
     public static AgeBiomeSelection compile(WritingGrammar.Result writing, AgeTraits traits,
                                              AgeRuntimeProfile profile, long seed, RegistryAccess registries) {
+        return compile(writing, traits, profile, seed, registries, RandomPagePolicy.UNRESTRICTED);
+    }
+
+    public static AgeBiomeSelection compile(WritingGrammar.Result writing, AgeTraits traits,
+                                             AgeRuntimeProfile profile, long seed, RegistryAccess registries,
+                                             RandomPagePolicy policy) {
         List<ResourceLocation> authored = writing.symbols().stream()
                 .filter(symbol -> symbol.semantics().role() == SymbolSemantics.Role.BIOME)
                 .map(symbol -> ((SymbolSemantics.ResourceValue) symbol.semantics().value()).id()).toList();
@@ -67,10 +74,26 @@ public record AgeBiomeSelection(AgeTraits.BiomeDistribution distribution, List<R
                         + " or a TerraBlender Nether region");
             }
         }
-        List<ResourceLocation> availableBiomes = eligible(registries, profile);
-        if (availableBiomes.isEmpty()) throw new IllegalArgumentException("No eligible biomes for terrain " + profile.noiseSettings());
+        List<ResourceLocation> terrainBiomes = eligible(registries, profile);
+        if (terrainBiomes.isEmpty()) throw new IllegalArgumentException("No eligible biomes for terrain " + profile.noiseSettings());
+        List<ResourceLocation> availableBiomes = distribution == AgeTraits.BiomeDistribution.NATIVE
+                ? terrainBiomes : new ArrayList<>(policy.eligible(terrainBiomes, BiomeSymbolPages::symbolId));
+        if (distribution != AgeTraits.BiomeDistribution.NATIVE
+                && new LinkedHashSet<>(availableBiomes).size() < minimum(distribution)) {
+            ResourceLocation preferred = profile.terrain() == AgeRuntimeProfile.Terrain.VOID
+                    ? ResourceLocation.withDefaultNamespace("the_void")
+                    : cave ? ResourceLocation.withDefaultNamespace("deep_dark")
+                    : ResourceLocation.withDefaultNamespace("plains");
+            if (terrainBiomes.contains(preferred) && !availableBiomes.contains(preferred))
+                availableBiomes.add(preferred);
+            for (ResourceLocation fallback : terrainBiomes) {
+                if (new LinkedHashSet<>(availableBiomes).size() >= minimum(distribution)) break;
+                if (!availableBiomes.contains(fallback)) availableBiomes.add(fallback);
+            }
+        }
         if (distribution == AgeTraits.BiomeDistribution.NATIVE) {
             if (!authored.isEmpty()) throw new IllegalArgumentException("Native biome distribution cannot use biome pages");
+            // Native noise biomes are supplied by Minecraft's preset, not chosen as Pages.
             return new AgeBiomeSelection(distribution, profile.terrain() == AgeRuntimeProfile.Terrain.FLAT
                     ? List.of(ResourceLocation.withDefaultNamespace("plains"))
                     : isCave(profile) ? availableBiomes : presetBiomes(registries, profile));

src/main/java/net/dnorberg/rivencraft/book/AgeDefinition.java

@@ -23,7 +23,8 @@ public record AgeDefinition(
         @Nullable AgeSeasonMode seasonMode,
         List<AgeFeatureSelection.Choice> randomFeatures,
         AgeInstability instability,
-        AgeInstabilityPlan instabilityPlan
+        AgeInstabilityPlan instabilityPlan,
+        RandomPagePolicy randomPagePolicy
 ) {
     public static final ResourceLocation RANDOM_VANILLA_PROFILE = ResourceLocation.fromNamespaceAndPath(
             Rivencraft.MOD_ID, "random_vanilla"
@@ -39,6 +40,7 @@ public record AgeDefinition(
         Objects.requireNonNull(traits, "traits");
         Objects.requireNonNull(instability, "instability");
         Objects.requireNonNull(instabilityPlan, "instabilityPlan");
+        Objects.requireNonNull(randomPagePolicy, "randomPagePolicy");
         randomFeatures = List.copyOf(randomFeatures);
         if (plan != null && !randomFeatures.isEmpty()) {
             throw new IllegalArgumentException("Authored Ages cannot also have random features");
@@ -88,6 +90,16 @@ public record AgeDefinition(
                 AgeInstabilityPlan.empty());
     }
 
+    public AgeDefinition(UUID id, String name, long seed, ResourceLocation generationProfile,
+                         int generationVersion, long createdGameTime, ResourceLocation dimensionId,
+                         BlockPos spawn, AgeTraits traits, AgeGenerationPlan plan,
+                         @Nullable AgeSeasonMode seasonMode, List<AgeFeatureSelection.Choice> randomFeatures,
+                         AgeInstability instability, AgeInstabilityPlan instabilityPlan) {
+        this(id, name, seed, generationProfile, generationVersion, createdGameTime,
+                dimensionId, spawn, traits, plan, seasonMode, randomFeatures, instability,
+                instabilityPlan, RandomPagePolicy.UNRESTRICTED);
+    }
+
     public static ResourceLocation dimensionId(UUID ageId) {
         return ResourceLocation.fromNamespaceAndPath(Rivencraft.MOD_ID, "age/" + ageId);
     }
@@ -117,7 +129,7 @@ public record AgeDefinition(
     public AgeDefinition withSpawn(BlockPos spawn) {
         return new AgeDefinition(id, name, seed, generationProfile, generationVersion,
                 createdGameTime, dimensionId, spawn.immutable(), traits, plan, seasonMode,
-                randomFeatures, instability, instabilityPlan);
+                randomFeatures, instability, instabilityPlan, randomPagePolicy);
     }
 
     /** A frozen authored profile takes precedence over the profile ID on old books. */

src/main/java/net/dnorberg/rivencraft/book/AgeDimensionService.java

@@ -465,7 +465,7 @@ public final class AgeDimensionService {
         AgeBiomeSelection selection = age.plan() != null && age.plan().biomeSelection() != null
                 ? age.plan().biomeSelection()
                 : AgeBiomeSelection.compile(net.dnorberg.rivencraft.writing.WritingGrammar.parse(OrderedWriting.EMPTY),
-                        age.traits(), profile, age.seed(), server.registryAccess());
+                        age.traits(), profile, age.seed(), server.registryAccess(), age.randomPagePolicy());
         var registry = server.registryAccess().lookupOrThrow(Registries.BIOME);
         List<Holder<Biome>> biomes = new ArrayList<>();
         List<ResourceLocation> fallbacks = AgeBiomeSelection.eligible(server.registryAccess(), profile);

src/main/java/net/dnorberg/rivencraft/book/AgeFeatureSelection.java

@@ -158,12 +158,19 @@ public final class AgeFeatureSelection {
 
     /** Page-free Ages roll up to two material features, plus rare Skylands, once at creation. */
     public static List<Choice> randomChoices(long ageSeed, AgeRuntimeProfile profile, RegistryAccess registries) {
+        return randomChoices(ageSeed, profile, registries, RandomPagePolicy.UNRESTRICTED);
+    }
+
+    public static List<Choice> randomChoices(long ageSeed, AgeRuntimeProfile profile, RegistryAccess registries,
+                                             RandomPagePolicy policy) {
         Random random = new Random(ageSeed ^ 0x4D4154455249414CL);
         int count = random.nextInt(3);
         List<LegacyRankChoice.Option<ResourceLocation>> features = new ArrayList<>();
-        for (ResourceLocation id : BLOCK_FEATURES) if (error(id, profile, registries) == null)
+        for (ResourceLocation id : BLOCK_FEATURES) if (error(id, profile, registries) == null
+                && policy.allows(featurePage(id)))
             features.add(new LegacyRankChoice.Option<>(id, randomMaterialRank(id)));
-        for (ResourceLocation id : FLUID_FEATURES) if (error(id, profile, registries) == null)
+        for (ResourceLocation id : FLUID_FEATURES) if (error(id, profile, registries) == null
+                && policy.allows(featurePage(id)))
             features.add(new LegacyRankChoice.Option<>(id, randomMaterialRank(id)));
         List<Choice> choices = new ArrayList<>();
         while (choices.size() < count && !features.isEmpty()) {
@@ -172,23 +179,30 @@ public final class AgeFeatureSelection {
             var category = solidFeature(feature)
                     ? BlockSymbolPages.CATEGORY : BlockSymbolPages.FLUID_CATEGORY;
             List<ResourceLocation> materials = BlockSymbolPages.availableBlocks(category).stream()
+                    .filter(id -> policy.allows(BlockSymbolPages.symbolId(id)))
                     .filter(id -> materialError(new Choice(feature, Optional.of(id))) == null).toList();
             if (!materials.isEmpty()) choices.add(new Choice(feature,
                     Optional.of(materials.get(random.nextInt(materials.size())))));
         }
         if (profile.terrain() == AgeRuntimeProfile.Terrain.NOISE
+                && policy.allows(featurePage(id("skylands")))
                 && Math.floorMod(mix(ageSeed ^ RANDOM_SKYLANDS_SALT), 8) == 0)
             choices.add(new Choice(id("skylands"), Optional.empty()));
-        if (error(CRYSTAL_FORMATIONS, profile, registries) == null && random.nextInt(10) == 0)
+        if (error(CRYSTAL_FORMATIONS, profile, registries) == null
+                && policy.allows(featurePage(CRYSTAL_FORMATIONS)) && random.nextInt(10) == 0)
             choices.add(new Choice(CRYSTAL_FORMATIONS, Optional.empty()));
-        if (randomStarFissure(ageSeed))
+        if (policy.allows(featurePage(STAR_FISSURES)) && randomStarFissure(ageSeed))
             choices.add(new Choice(STAR_FISSURES, Optional.empty()));
         AgeBiomeSelection biomes = AgeBiomeSelection.compile(WritingGrammar.parse(OrderedWriting.EMPTY),
-                AgeTraits.select(ageSeed), profile, ageSeed, registries);
-        choices.addAll(AgeStructureSelection.randomChoices(ageSeed, profile, biomes, registries));
+                AgeTraits.select(ageSeed, policy), profile, ageSeed, registries, policy);
+        choices.addAll(AgeStructureSelection.randomChoices(ageSeed, profile, biomes, registries, policy));
         return List.copyOf(choices);
     }
 
+    private static ResourceLocation featurePage(ResourceLocation id) {
+        return ResourceLocation.fromNamespaceAndPath("rivencraft", "feature/" + id.getPath());
+    }
+
     static int randomMaterialRank(ResourceLocation feature) {
         if (feature.equals(id("surface_lakes")) || feature.equals(id("deep_lakes"))) return 1;
         if (feature.equals(id("lava_lakes"))) return 2; // New separate fluid choice.

src/main/java/net/dnorberg/rivencraft/book/AgeInstability.java

@@ -56,6 +56,11 @@ public record AgeInstability(int version, int score, List<Contribution> breakdow
     }
 
     static AgeInstability compute(AgeGenerationPlan plan, AgeTraits traits, RegistryAccess registries, long ageSeed) {
+        return compute(plan, traits, registries, ageSeed, RandomPagePolicy.UNRESTRICTED);
+    }
+
+    static AgeInstability compute(AgeGenerationPlan plan, AgeTraits traits, RegistryAccess registries,
+                                  long ageSeed, RandomPagePolicy policy) {
         Objects.requireNonNull(traits, "traits");
         List<Contribution> contributions = new ArrayList<>();
         if (plan == null) {
@@ -87,7 +92,7 @@ public record AgeInstability(int version, int score, List<Contribution> breakdow
             contributions.add(new Contribution("bright_lighting", -1, BRIGHT_LIGHTING_COST,
                     "Seeded bright lighting"));
         }
-        AgeSkyProfile sky = plan == null && ageSeed != Long.MIN_VALUE ? AgeSkyProfile.random(ageSeed, traits)
+        AgeSkyProfile sky = plan == null && ageSeed != Long.MIN_VALUE ? AgeSkyProfile.random(ageSeed, traits, policy)
                 : plan == null ? new AgeSkyProfile(AgeSkyProfile.Style.INHERITED, -1, List.of())
                 : AgeSkyProfile.compile(plan, traits);
         int seenSuns = 0;

src/main/java/net/dnorberg/rivencraft/book/AgeRegistrySavedData.java

@@ -39,6 +39,7 @@ public final class AgeRegistrySavedData extends SavedData {
     private static final String TRAITS_TAG = "Traits";
     private static final String PLAN_TAG = "GenerationPlan";
     private static final String RANDOM_FEATURES_TAG = "RandomFeatures";
+    private static final String RANDOM_PAGE_POLICY_TAG = "RandomPagePolicy";
     private static final String SEASON_MODE_TAG = "SeasonMode";
     private static final String INSTABILITY_TAG = "Instability";
     private static final String INSTABILITY_PLAN_TAG = "InstabilityPlan";
@@ -77,9 +78,19 @@ public final class AgeRegistrySavedData extends SavedData {
         ServerLevel overworld = level.getServer().overworld();
         AgeRegistrySavedData data = get(overworld);
         long seed = ageSeed(overworld.getSeed(), data.availableDimensionId(normalizedName(name)));
-        AgeGenerationPlan.compile(writing, seed,
+        AgeGenerationPlan plan = AgeGenerationPlan.compile(writing, seed,
                 AgeRuntimeProfiles.selectForWriting(seed, writing, overworld.registryAccess()), AgeTraits.select(seed),
                 overworld.registryAccess());
+        if (plan == null) {
+            RandomPagePolicy policy = RandomPagePolicy.configured();
+            ResourceLocation profileId = AgeRuntimeProfiles.select(seed, policy);
+            AgeRuntimeProfile profile = AgeRuntimeProfiles.resolve(profileId);
+            AgeTraits traits = AgeTraits.select(seed, policy);
+            AgeBiomeSelection.compile(net.dnorberg.rivencraft.writing.WritingGrammar.parse(OrderedWriting.EMPTY),
+                    traits, profile, seed, overworld.registryAccess(), policy);
+            AgeSkyProfile.random(seed, traits, policy);
+            AgeSeasonMode.select(null, seed, ModList.get().isLoaded("sereneseasons"), profile, policy);
+        }
     }
 
     public static ResourceLocation previewGenerationProfile(ServerLevel level, String name) {
@@ -155,7 +166,8 @@ public final class AgeRegistrySavedData extends SavedData {
         AgeDefinition changed = new AgeDefinition(previous.id(), previous.name(), seed,
                 previous.generationProfile(), previous.generationVersion(), previous.createdGameTime(),
                 previous.dimensionId(), previous.spawn(), previous.traits(), plan, previous.seasonMode(),
-                previous.randomFeatures(), previous.instability(), previous.instabilityPlan());
+                previous.randomFeatures(), previous.instability(), previous.instabilityPlan(),
+                previous.randomPagePolicy());
         if (AgeDimensionService.unload(server, previous) == AgeDimensionService.UnloadResult.FAILED)
             return false;
         ages.put(ageId, changed);
@@ -173,13 +185,19 @@ public final class AgeRegistrySavedData extends SavedData {
         String name = normalizedName(reference.name());
         ResourceLocation dimensionId = availableDimensionId(name);
         long seed = ageSeed(worldSeed, dimensionId);
+        RandomPagePolicy policy = RandomPagePolicy.configured();
         ResourceLocation seedProfile = AgeRuntimeProfiles.selectForWriting(seed, writing, registries);
         AgeTraits traits = AgeTraits.select(seed);
         AgeGenerationPlan plan = AgeGenerationPlan.compile(writing, seed, seedProfile, traits, registries);
+        if (plan == null) {
+            seedProfile = AgeRuntimeProfiles.select(seed, policy);
+            traits = AgeTraits.select(seed, policy);
+        }
         AgeTraits effectiveTraits = plan == null
                 ? AgeEnvironmentCompiler.forTerrain(traits, AgeRuntimeProfiles.resolve(seedProfile))
                 : AgeEnvironmentCompiler.apply(plan, traits);
-        AgeInstability instability = AgeInstability.compute(plan, effectiveTraits, registries, seed);
+        AgeInstability instability = AgeInstability.compute(plan, effectiveTraits, registries, seed,
+                plan == null ? policy : RandomPagePolicy.UNRESTRICTED);
         AgeInstabilityPlan instabilityPlan = AgeInstabilityPlan.select(instability, seed);
         AgeDefinition created = new AgeDefinition(
                 reference.id(),
@@ -193,11 +211,13 @@ public final class AgeRegistrySavedData extends SavedData {
                 effectiveTraits,
                 plan,
                 AgeSeasonMode.select(plan, seed, ModList.get().isLoaded("sereneseasons"),
-                        plan == null ? AgeRuntimeProfiles.resolve(seedProfile) : plan.runtimeProfile()),
+                        plan == null ? AgeRuntimeProfiles.resolve(seedProfile) : plan.runtimeProfile(),
+                        plan == null ? policy : RandomPagePolicy.UNRESTRICTED),
                 plan == null ? AgeFeatureSelection.randomChoices(seed,
-                        AgeRuntimeProfiles.resolve(seedProfile), registries) : List.of(),
+                        AgeRuntimeProfiles.resolve(seedProfile), registries, policy) : List.of(),
                 instability,
-                instabilityPlan
+                instabilityPlan,
+                plan == null ? policy : RandomPagePolicy.UNRESTRICTED
         );
         ages.put(created.id(), created);
         setDirty();
@@ -264,7 +284,10 @@ public final class AgeRegistrySavedData extends SavedData {
                             ? AgeSeasonMode.parseOrNull(entry.getString(SEASON_MODE_TAG)) : null,
                     readRandomFeatures(entry),
                     instability,
-                    instabilityPlan
+                    instabilityPlan,
+                    entry.contains(RANDOM_PAGE_POLICY_TAG, CompoundTag.TAG_COMPOUND)
+                            ? RandomPagePolicy.load(entry.getCompound(RANDOM_PAGE_POLICY_TAG))
+                            : RandomPagePolicy.UNRESTRICTED
             ));
         }
         return data;
@@ -309,6 +332,7 @@ public final class AgeRegistrySavedData extends SavedData {
                         entry.put(RANDOM_FEATURES_TAG, featureTags);
                     }
                     if (age.seasonMode() != null) entry.putString(SEASON_MODE_TAG, age.seasonMode().name());
+                    if (age.plan() == null) entry.put(RANDOM_PAGE_POLICY_TAG, age.randomPagePolicy().save());
                     entry.put(INSTABILITY_TAG, age.instability().save());
                     entry.put(INSTABILITY_PLAN_TAG, age.instabilityPlan().save());
                     serializedAges.add(entry);

src/main/java/net/dnorberg/rivencraft/book/AgeRuntimeProfiles.java

@@ -57,20 +57,39 @@ public final class AgeRuntimeProfiles {
 
     /** Selects from all valid loaded profiles in stable resource-ID order. */
     public static ResourceLocation select(long seed) {
+        return select(seed, RandomPagePolicy.UNRESTRICTED);
+    }
+
+    public static ResourceLocation select(long seed, RandomPagePolicy policy) {
         if (PROFILES.isEmpty()) {
-            return AgeGenerationProfiles.select(seed);
+            List<LegacyRankChoice.Option<ResourceLocation>> profiles = policy.required(
+                    AgeGenerationProfiles.all().stream().sorted()
+                            .map(id -> new LegacyRankChoice.Option<>(id, AgeGenerationProfiles.randomRank(id)))
+                            .toList(), option -> terrainPage(option.value()),
+                    new LegacyRankChoice.Option<>(AgeGenerationProfiles.STANDARD, 1));
+            return LegacyRankChoice.choose(new Random(seed ^ 0x5445525241494E4CL), profiles);
         }
-        List<LegacyRankChoice.Option<ResourceLocation>> profiles = PROFILES.keySet().stream().sorted()
+        List<LegacyRankChoice.Option<ResourceLocation>> available = PROFILES.keySet().stream().sorted()
                 .map(id -> new LegacyRankChoice.Option<>(id, AgeGenerationProfiles.randomRank(id))).toList();
+        LegacyRankChoice.Option<ResourceLocation> fallback = available.stream()
+                .filter(option -> option.value().equals(AgeGenerationProfiles.STANDARD))
+                .findFirst().orElse(available.getFirst());
+        List<LegacyRankChoice.Option<ResourceLocation>> profiles = policy.required(available,
+                option -> terrainPage(option.value()), fallback);
         return LegacyRankChoice.choose(new Random(seed ^ 0x5445525241494E4CL), profiles);
     }
 
+    private static ResourceLocation terrainPage(ResourceLocation profile) {
+        return ResourceLocation.fromNamespaceAndPath("rivencraft", "terrain/" + profile.getPath());
+    }
+
     /** Keep seed-selected terrain random, but only among profiles able to host authored features. */
     public static ResourceLocation selectForWriting(long seed, OrderedWriting writing, RegistryAccess registries) {
-        ResourceLocation selected = select(seed);
         WritingGrammar.Result parsed = WritingGrammar.parse(writing);
-        if (parsed.activeSymbols().stream().anyMatch(symbol ->
-                symbol.semantics().role() == SymbolSemantics.Role.TERRAIN)) return selected;
+        boolean authoredTerrain = parsed.activeSymbols().stream().anyMatch(symbol ->
+                symbol.semantics().role() == SymbolSemantics.Role.TERRAIN);
+        ResourceLocation selected = select(seed);
+        if (authoredTerrain) return selected;
         List<ResourceLocation> features = parsed.activeSymbols().stream()
                 .filter(symbol -> symbol.semantics().role() == SymbolSemantics.Role.FEATURE)
                 .map(symbol -> ((SymbolSemantics.ResourceValue) symbol.semantics().value()).id()).toList();

src/main/java/net/dnorberg/rivencraft/book/AgeSeasonMode.java

@@ -24,15 +24,23 @@ public enum AgeSeasonMode {
 
     public static AgeSeasonMode select(AgeGenerationPlan plan, long ageSeed, boolean sereneInstalled,
                                        AgeRuntimeProfile profile) {
+        return select(plan, ageSeed, sereneInstalled, profile, RandomPagePolicy.UNRESTRICTED);
+    }
+
+    public static AgeSeasonMode select(AgeGenerationPlan plan, long ageSeed, boolean sereneInstalled,
+                                       AgeRuntimeProfile profile, RandomPagePolicy policy) {
         if (profile != null && AgeBiomeSelection.isCave(profile)) return NO_SEASONS;
         if (hasAuthoredPage(plan)) return from(plan);
-        return sereneInstalled ? LegacyRankChoice.choose(new Random(ageSeed ^ RANDOM_SALT), List.of(
+        return sereneInstalled ? LegacyRankChoice.choose(new Random(ageSeed ^ RANDOM_SALT), policy.required(List.of(
                 new LegacyRankChoice.Option<>(SEASONS, 1),
                 new LegacyRankChoice.Option<>(NO_SEASONS, 2),
                 new LegacyRankChoice.Option<>(ETERNAL_WINTER, 3),
                 new LegacyRankChoice.Option<>(ETERNAL_SUMMER, 3),
                 new LegacyRankChoice.Option<>(ETERNAL_FALL, 3),
-                new LegacyRankChoice.Option<>(ETERNAL_SPRING, 3))) : null;
+                new LegacyRankChoice.Option<>(ETERNAL_SPRING, 3)),
+                option -> net.minecraft.resources.ResourceLocation.fromNamespaceAndPath("rivencraft",
+                        "season/" + option.value().name().toLowerCase(Locale.ROOT)),
+                new LegacyRankChoice.Option<>(NO_SEASONS, 2))) : null;
     }
 
     /** Existing Ages without a stored choice retain their old cycling behavior. */

src/main/java/net/dnorberg/rivencraft/book/AgeSkyProfile.java

@@ -6,6 +6,7 @@ import java.util.List;
 import java.util.Random;
 import java.util.Set;
 import net.dnorberg.rivencraft.writing.SymbolSemantics;
+import net.minecraft.resources.ResourceLocation;
 
 /** The ordered, deterministic sky specification for an Age. No client data is trusted here. */
 public record AgeSkyProfile(Style style, int color, List<Body> bodies) {
@@ -23,16 +24,25 @@ public record AgeSkyProfile(Style style, int color, List<Body> bodies) {
     public static AgeSkyProfile forAge(AgeDefinition age) {
         if (age.plan() != null) return compile(age.plan(), age.traits());
         if (age.generationVersion() >= RANDOM_SKY_GENERATION_VERSION)
-            return random(age.seed(), age.traits());
+            return random(age.seed(), age.traits(), age.randomPagePolicy());
         return new AgeSkyProfile(Style.INHERITED, -1, List.of());
     }
 
     public static AgeSkyProfile random(long seed, AgeTraits traits) {
+        return random(seed, traits, RandomPagePolicy.UNRESTRICTED);
+    }
+
+    public static AgeSkyProfile random(long seed, AgeTraits traits, RandomPagePolicy policy) {
         Random random = new Random(seed ^ 0x534B5950524F464CL);
-        Style style = Style.values()[random.nextInt(Style.values().length)];
+        List<Style> styles = policy.required(java.util.Arrays.stream(Style.values())
+                .filter(style -> style != Style.INHERITED || !policy.restricts("sky")).toList(),
+                AgeSkyProfile::skyPage, Style.INHERITED);
+        Style style = styles.get(random.nextInt(styles.size()));
         int color = randomColor(random);
-        int suns = random.nextInt(4);
-        int moons = random.nextInt(4);
+        int suns = policy.allows(ResourceLocation.fromNamespaceAndPath("rivencraft", "celestial/sun"))
+                ? random.nextInt(4) : 0;
+        int moons = policy.allows(ResourceLocation.fromNamespaceAndPath("rivencraft", "celestial/moon"))
+                ? random.nextInt(4) : 0;
         List<Body> bodies = new ArrayList<>();
         for (int i = 0; i < suns; i++)
             bodies.add(new Body(Kind.SUN, randomColor(random),
@@ -45,6 +55,11 @@ public record AgeSkyProfile(Style style, int color, List<Body> bodies) {
         return new AgeSkyProfile(style, color, bodies);
     }
 
+    private static ResourceLocation skyPage(Style style) {
+        return ResourceLocation.fromNamespaceAndPath("rivencraft",
+                "sky/" + (style == Style.INHERITED ? "inherited" : style.name().toLowerCase(java.util.Locale.ROOT)));
+    }
+
     public static AgeSkyProfile compile(AgeGenerationPlan plan, AgeTraits traits) {
         if (plan == null) return new AgeSkyProfile(Style.INHERITED, -1, List.of());
         Style style = Style.INHERITED;
@@ -86,7 +101,7 @@ public record AgeSkyProfile(Style style, int color, List<Body> bodies) {
                 case PERIOD_MODIFIER -> period = CelestialPageValues.value(semantics, number);
                 case ANGLE_MODIFIER -> angle = (float) CelestialPageValues.value(semantics, number);
                 case PHASE_MODIFIER -> phase = (float) (CelestialPageValues.value(semantics, number) / 360.0D);
-                case SIZE_MODIFIER -> size = (float) ((SymbolSemantics.NumberValue) semantics.value()).amount();
+                case SIZE_MODIFIER -> size = (float) CelestialPageValues.value(semantics, number);
                 case CELESTIAL_COLOR -> bodyColors.add(color(
                         ((SymbolSemantics.ChoiceValue) semantics.value()).id()));
                 case DIRECTION_MODIFIER -> clockwise = ((SymbolSemantics.ChoiceValue) semantics.value())

src/main/java/net/dnorberg/rivencraft/book/AgeStructureSelection.java

@@ -157,7 +157,14 @@ public final class AgeStructureSelection {
 
     public static List<AgeFeatureSelection.Choice> randomChoices(long ageSeed, AgeRuntimeProfile profile,
                                                                    AgeBiomeSelection biomes, RegistryAccess registries) {
+        return randomChoices(ageSeed, profile, biomes, registries, RandomPagePolicy.UNRESTRICTED);
+    }
+
+    public static List<AgeFeatureSelection.Choice> randomChoices(long ageSeed, AgeRuntimeProfile profile,
+                                                                   AgeBiomeSelection biomes, RegistryAccess registries,
+                                                                   RandomPagePolicy policy) {
         List<LegacyRankChoice.Option<ResourceLocation>> eligible = new ArrayList<>(FEATURES.stream()
+                .filter(id -> policy.allows(ResourceLocation.fromNamespaceAndPath("rivencraft", "feature/" + id.getPath())))
                 .filter(id -> error(id, profile, biomes, registries) == null)
                 .filter(id -> dungeons(id) || biomeCompatible(id, biomes, registries))
                 .map(id -> new LegacyRankChoice.Option<>(id, randomRank(id))).toList());

src/main/java/net/dnorberg/rivencraft/book/AgeTraits.java

@@ -2,6 +2,8 @@ package net.dnorberg.rivencraft.book;
 
 import java.util.Random;
 import java.util.List;
+import java.util.Locale;
+import net.minecraft.resources.ResourceLocation;
 
 /** Immutable random-Age traits selected once from the Age seed. */
 public record AgeTraits(
@@ -42,8 +44,12 @@ public record AgeTraits(
     }
 
     public static AgeTraits select(long seed) {
+        return select(seed, RandomPagePolicy.UNRESTRICTED);
+    }
+
+    public static AgeTraits select(long seed, RandomPagePolicy policy) {
         Random random = new Random(seed ^ 0x524956454E435241L);
-        BiomeDistribution biomeDistribution = LegacyRankChoice.choose(random, List.of(
+        BiomeDistribution biomeDistribution = LegacyRankChoice.choose(random, policy.required(List.of(
                 new LegacyRankChoice.Option<>(BiomeDistribution.NATIVE, 1),
                 new LegacyRankChoice.Option<>(BiomeDistribution.SINGLE, 1),
                 new LegacyRankChoice.Option<>(BiomeDistribution.MEDIUM, 1),
@@ -52,12 +58,16 @@ public record AgeTraits(
                 new LegacyRankChoice.Option<>(BiomeDistribution.TINY, 2),
                 new LegacyRankChoice.Option<>(BiomeDistribution.SMALL, 2),
                 new LegacyRankChoice.Option<>(BiomeDistribution.LARGE, 2),
-                new LegacyRankChoice.Option<>(BiomeDistribution.HUGE, 2)));
-        Lighting lighting = LegacyRankChoice.choose(random, List.of(
+                new LegacyRankChoice.Option<>(BiomeDistribution.HUGE, 2)),
+                option -> page("biome", option.value()),
+                new LegacyRankChoice.Option<>(BiomeDistribution.NATIVE, 1)));
+        Lighting lighting = LegacyRankChoice.choose(random, policy.required(List.of(
                 new LegacyRankChoice.Option<>(Lighting.NORMAL, 1),
                 new LegacyRankChoice.Option<>(Lighting.DARK, 2),
-                new LegacyRankChoice.Option<>(Lighting.BRIGHT, 2)));
-        Weather weather = LegacyRankChoice.choose(random, List.of(
+                new LegacyRankChoice.Option<>(Lighting.BRIGHT, 2)),
+                option -> page("lighting", option.value()),
+                new LegacyRankChoice.Option<>(Lighting.NORMAL, 1)));
+        Weather weather = LegacyRankChoice.choose(random, policy.required(List.of(
                 new LegacyRankChoice.Option<>(Weather.NORMAL, 1),
                 new LegacyRankChoice.Option<>(Weather.FAST, 2),
                 new LegacyRankChoice.Option<>(Weather.SLOW, 2),
@@ -66,7 +76,9 @@ public record AgeTraits(
                 new LegacyRankChoice.Option<>(Weather.CLOUDY, 2),
                 new LegacyRankChoice.Option<>(Weather.RAIN, 2),
                 new LegacyRankChoice.Option<>(Weather.SNOW, 2),
-                new LegacyRankChoice.Option<>(Weather.STORM, 2)));
+                new LegacyRankChoice.Option<>(Weather.STORM, 2)),
+                option -> page("weather", option.value()),
+                new LegacyRankChoice.Option<>(Weather.NORMAL, 1)));
         // Legacy's PERIOD_BASIC grammar gives ModZero rank 2 and its other
         // three length modifiers rank 1, producing an effective 1-in-7 weight.
         boolean stopped = random.nextInt(7) == 0;
@@ -81,6 +93,11 @@ public record AgeTraits(
         );
     }
 
+    private static ResourceLocation page(String category, Enum<?> value) {
+        return ResourceLocation.fromNamespaceAndPath("rivencraft",
+                category + "/" + value.name().toLowerCase(Locale.ROOT));
+    }
+
     public boolean hasStoppedCelestialCycle() {
         return celestialPeriod == STOPPED_CELESTIAL_PERIOD;
     }

src/main/java/net/dnorberg/rivencraft/book/CelestialPageValues.java

@@ -11,6 +11,7 @@ final class CelestialPageValues {
         return switch (semantics.role()) {
             case PERIOD_MODIFIER -> number * 0.08D;
             case ANGLE_MODIFIER, PHASE_MODIFIER -> (number * 15.0D) % 360.0D;
+            case SIZE_MODIFIER -> 0.25D + number * (2.75D / 24.0D);
             default -> throw new IllegalArgumentException("Not a celestial numeric modifier");
         };
     }

src/main/java/net/dnorberg/rivencraft/book/CelestialSizeGameTests.java

@@ -0,0 +1,64 @@
+package net.dnorberg.rivencraft.book;
+
+import java.util.List;
+import net.dnorberg.rivencraft.Rivencraft;
+import net.dnorberg.rivencraft.writing.OrderedWriting;
+import net.dnorberg.rivencraft.writing.SymbolReference;
+import net.dnorberg.rivencraft.writing.WritingEntry;
+import net.dnorberg.rivencraft.writing.WritingGrammar;
+import net.minecraft.gametest.framework.GameTest;
+import net.minecraft.gametest.framework.GameTestHelper;
+import net.minecraft.resources.ResourceLocation;
+import net.neoforged.neoforge.gametest.GameTestHolder;
+import net.neoforged.neoforge.gametest.PrefixGameTestTemplate;
+
+/** Focused core coverage without launching the storage-heavy environment archive. */
+@GameTestHolder(Rivencraft.MOD_ID)
+@PrefixGameTestTemplate(false)
+public final class CelestialSizeGameTests {
+    private CelestialSizeGameTests() {}
+
+    @GameTest(template = "empty")
+    public static void adjacentNumberSetsNextCelestialSize(GameTestHelper helper) {
+        OrderedWriting writing = new OrderedWriting(List.of(WritingEntry.linkPanel(),
+                page("number/0"), page("size/small"), page("celestial/sun"),
+                page("number/24"), page("size/large"), page("celestial/moon"),
+                page("number/12"), page("size/normal"), page("celestial/sun")));
+        helper.assertValueEqual(WritingGrammar.parse(writing).writingInstability(), 0,
+                "Adjacent number and size pages must be valid writing");
+        AgeTraits seeded = AgeTraits.select(94L);
+        AgeGenerationPlan plan = AgeGenerationPlan.compile(writing, 94L,
+                AgeGenerationProfiles.STANDARD, seeded, helper.getLevel().registryAccess());
+        AgeSkyProfile sky = AgeSkyProfile.compile(plan, AgeEnvironmentCompiler.apply(plan, seeded));
+        helper.assertValueEqual(sky.bodies().size(), 3, "Three authored bodies must remain distinct");
+        helper.assertValueEqual(sky.bodies().get(0).size(), 0.25F, "Digit zero selects minimum size");
+        helper.assertValueEqual(sky.bodies().get(1).size(), 3.0F, "Digit 24 selects maximum size");
+        helper.assertValueEqual(sky.bodies().get(2).size(), 1.625F, "Digit 12 selects midpoint size");
+        helper.assertValueEqual(AgeSkyProfile.compile(AgeGenerationPlan.load(plan.save()),
+                AgeEnvironmentCompiler.apply(plan, seeded)), sky,
+                "Numbered sizes must survive an Age-plan save/load round trip");
+
+        OrderedWriting plain = new OrderedWriting(List.of(WritingEntry.linkPanel(),
+                page("size/small"), page("celestial/sun"),
+                page("size/normal"), page("celestial/moon"),
+                page("size/large"), page("celestial/sun")));
+        AgeGenerationPlan plainPlan = AgeGenerationPlan.compile(plain, 95L,
+                AgeGenerationProfiles.STANDARD, AgeTraits.select(95L), helper.getLevel().registryAccess());
+        AgeSkyProfile plainSky = AgeSkyProfile.compile(plainPlan,
+                AgeEnvironmentCompiler.apply(plainPlan, AgeTraits.select(95L)));
+        helper.assertValueEqual(plainSky.bodies().get(0).size(), 0.5F, "Small retains its fixed value");
+        helper.assertValueEqual(plainSky.bodies().get(1).size(), 1.0F, "Normal retains its fixed value");
+        helper.assertValueEqual(plainSky.bodies().get(2).size(), 2.0F, "Large retains its fixed value");
+
+        OrderedWriting separated = new OrderedWriting(List.of(WritingEntry.linkPanel(),
+                page("number/24"), page("direction/clockwise"),
+                page("size/large"), page("celestial/sun")));
+        helper.assertValueEqual(WritingGrammar.parse(separated).writingInstability(), 100,
+                "An intervening page must not allow a number to modify size");
+        helper.succeed();
+    }
+
+    private static WritingEntry page(String path) {
+        return WritingEntry.symbol(new SymbolReference(ResourceLocation.fromNamespaceAndPath("rivencraft", path)));
+    }
+}

src/main/java/net/dnorberg/rivencraft/book/HandheldBookTravelGameTests.java

@@ -43,8 +43,9 @@ public final class HandheldBookTravelGameTests {
         helper.assertTrue(player.getInventory().getItem(1).is(Items.DIAMOND),
                 "An unrelated inventory item must remain with the player");
         var drops = helper.getLevel().getEntitiesOfClass(DroppedBookEntity.class, new AABB(source, source).inflate(2.0),
-                entity -> entity.getItem().is(ModItems.LINKING_BOOK.get()));
-        helper.assertValueEqual(drops.size(), 1, "Exactly one recoverable book must remain at the departure point");
+                entity -> entity.getItem() == book);
+        helper.assertValueEqual(drops.size(), 1,
+                "Exactly one entity for this active book must remain at the departure point");
         helper.assertTrue(drops.getFirst().getItem() == book,
                 "The model-rendered entity must retain the exact active book stack");
         helper.assertTrue(drops.getFirst().copy() instanceof DroppedBookEntity,

src/main/java/net/dnorberg/rivencraft/book/RandomPagePolicy.java

@@ -0,0 +1,91 @@
+package net.dnorberg.rivencraft.book;
+
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+import net.dnorberg.rivencraft.config.RivencraftConfig;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.nbt.ListTag;
+import net.minecraft.nbt.StringTag;
+import net.minecraft.resources.ResourceLocation;
+
+/** A snapshot of Page eligibility, frozen with each random Age at binding time. */
+public record RandomPagePolicy(Set<ResourceLocation> allowlist, Set<ResourceLocation> blocklist) {
+    public static final RandomPagePolicy UNRESTRICTED = new RandomPagePolicy(Set.of(), Set.of());
+
+    public RandomPagePolicy {
+        allowlist = Set.copyOf(allowlist);
+        blocklist = Set.copyOf(blocklist);
+    }
+
+    public static RandomPagePolicy configured() {
+        return new RandomPagePolicy(parse(RivencraftConfig.randomPageAllowlist()),
+                parse(RivencraftConfig.randomPageBlocklist()));
+    }
+
+    private static Set<ResourceLocation> parse(List<? extends String> ids) {
+        return ids.stream().map(RandomPagePolicy::parsePageId).collect(Collectors.toUnmodifiableSet());
+    }
+
+    /** Server config IDs may omit the built-in Rivencraft namespace. */
+    public static ResourceLocation parsePageId(String value) {
+        ResourceLocation id = ResourceLocation.tryParse(value.contains(":") ? value : "rivencraft:" + value);
+        if (id == null) throw new IllegalArgumentException("Invalid Page ID " + value);
+        return id;
+    }
+
+    public boolean allows(ResourceLocation id) {
+        if (blocklist.contains(id)) return false;
+        String category = category(id);
+        return !restricts(category) || allowlist.contains(id);
+    }
+
+    public boolean restricts(String category) {
+        return allowlist.stream().anyMatch(entry -> category(entry).equals(category));
+    }
+
+    public <T> List<T> eligible(List<T> candidates, java.util.function.Function<T, ResourceLocation> pageId) {
+        return candidates.stream().filter(candidate -> allows(pageId.apply(candidate))).toList();
+    }
+
+    public <T> List<T> required(List<T> candidates, java.util.function.Function<T, ResourceLocation> pageId,
+                                T fallback) {
+        List<T> eligible = eligible(candidates, pageId);
+        return eligible.isEmpty() ? List.of(fallback) : eligible;
+    }
+
+    private static String category(ResourceLocation id) {
+        String path = id.getPath();
+        if (path.startsWith("biome/") && java.util.Set.of("native", "single", "tiled", "grid",
+                "tiny", "small", "medium", "large", "huge").contains(path.substring("biome/".length())))
+            return "biome_distribution";
+        return path.substring(0, path.indexOf('/') < 0 ? path.length() : path.indexOf('/'));
+    }
+
+    public CompoundTag save() {
+        CompoundTag tag = new CompoundTag();
+        tag.put("Allowlist", strings(allowlist));
+        tag.put("Blocklist", strings(blocklist));
+        return tag;
+    }
+
+    public static RandomPagePolicy load(CompoundTag tag) {
+        return new RandomPagePolicy(read(tag.getList("Allowlist", StringTag.TAG_STRING)),
+                read(tag.getList("Blocklist", StringTag.TAG_STRING)));
+    }
+
+    private static ListTag strings(Set<ResourceLocation> ids) {
+        ListTag tags = new ListTag();
+        ids.stream().sorted().forEach(id -> tags.add(StringTag.valueOf(id.toString())));
+        return tags;
+    }
+
+    private static Set<ResourceLocation> read(ListTag tags) {
+        java.util.Set<ResourceLocation> ids = new java.util.HashSet<>();
+        for (int index = 0; index < tags.size(); index++) {
+            ResourceLocation id = ResourceLocation.tryParse(tags.getString(index));
+            if (id != null) ids.add(id);
+        }
+        return Set.copyOf(ids);
+    }
+}

src/main/java/net/dnorberg/rivencraft/client/screen/BookBinderScreen.java

@@ -107,7 +107,7 @@ public final class BookBinderScreen extends AbstractContainerScreen<BookBinderMe
         }
         graphics.disableScissor();
         drawScrollEnds(graphics);
-        var severity = menu.grammarSeverity().orElse(null);
+        var severity = menu.diagnosticsVisible() ? menu.grammarSeverity().orElse(null) : null;
         Component status = severity == WritingGrammar.Severity.FATAL
                 ? Component.translatable("screen.rivencraft.book_binder.status.fatal")
                 : severity == WritingGrammar.Severity.INSTABILITY
@@ -117,9 +117,9 @@ public final class BookBinderScreen extends AbstractContainerScreen<BookBinderMe
         if (status != null) graphics.drawString(font, status, leftPos + 77, topPos + 30,
                 severity == WritingGrammar.Severity.FATAL ? 0xFFAA3030
                         : severity == WritingGrammar.Severity.INSTABILITY ? 0xFF924F18 : 0xFF50624B, false);
-        Component grammarTooltip = menu.grammarError().map(code -> Component.translatable(
+        Component grammarTooltip = menu.diagnosticsVisible() ? menu.grammarError().map(code -> Component.translatable(
                 "screen.rivencraft.book_binder.grammar." + code.name().toLowerCase(Locale.ROOT),
-                errorStripIndex + 1)).orElse(null);
+                errorStripIndex + 1)).orElse(null) : null;
         if (grammarTooltip != null && ((mouseX >= leftPos + 77 && mouseX < leftPos + 151)
                 || (mouseX >= leftPos + 152 && mouseX < leftPos + 168))
                 && mouseY >= topPos + 27 && mouseY < topPos + 43

src/main/java/net/dnorberg/rivencraft/command/RivencraftCommands.java

@@ -12,6 +12,7 @@ import net.dnorberg.rivencraft.book.AgeRegistrySavedData;
 import net.dnorberg.rivencraft.book.AgeInstabilityControls;
 import net.dnorberg.rivencraft.book.AgeInstabilityRuntime;
 import net.dnorberg.rivencraft.config.RivencraftConfig;
+import net.dnorberg.rivencraft.menu.BookBinderDiagnostics;
 import net.minecraft.commands.Commands;
 import net.minecraft.commands.CommandSourceStack;
 import com.mojang.brigadier.builder.LiteralArgumentBuilder;
@@ -29,6 +30,13 @@ public final class RivencraftCommands {
     public static void register(RegisterCommandsEvent event) {
         event.getDispatcher().register(Commands.literal("rivencraft")
                 .requires(source -> source.hasPermission(2))
+                .then(Commands.literal("binder")
+                        .then(Commands.literal("messages")
+                                .executes(context -> binderMessages(context.getSource(), null))
+                                .then(Commands.literal("enable")
+                                        .executes(context -> binderMessages(context.getSource(), true)))
+                                .then(Commands.literal("disable")
+                                        .executes(context -> binderMessages(context.getSource(), false)))))
                 .then(Commands.literal("library")
                         .then(Commands.literal("nearest")
                                 .executes(context -> LibraryLocateService.start(context.getSource())))
@@ -94,6 +102,14 @@ public final class RivencraftCommands {
                         .then(environmentCommand())));
     }
 
+    private static int binderMessages(CommandSourceStack source, Boolean enabled) {
+        BookBinderDiagnostics diagnostics = BookBinderDiagnostics.get(source.getLevel());
+        if (enabled != null) diagnostics.setEnabled(enabled);
+        source.sendSuccess(() -> Component.literal("Book Binder diagnostic messages are "
+                + (diagnostics.enabled() ? "enabled for operators" : "disabled") + "."), false);
+        return diagnostics.enabled() ? 1 : 0;
+    }
+
     private static LiteralArgumentBuilder<CommandSourceStack> environmentCommand() {
         return Commands.literal("environment")
                 .then(Commands.literal("pulse")

src/main/java/net/dnorberg/rivencraft/config/RivencraftConfig.java

@@ -23,6 +23,8 @@ public final class RivencraftConfig {
     private static final ModConfigSpec.EnumValue<LibraryLootMode> LIBRARY_LOOT_MODE;
     private static final ModConfigSpec.IntValue SYMBOL_INK_COST;
     private static final ModConfigSpec.IntValue LINK_PANEL_INK_COST;
+    private static final ModConfigSpec.ConfigValue<List<? extends String>> RANDOM_PAGE_ALLOWLIST;
+    private static final ModConfigSpec.ConfigValue<List<? extends String>> RANDOM_PAGE_BLOCKLIST;
     private static final ModConfigSpec.BooleanValue AUTO_WHITELIST_SERENE_AGES;
     private static final ModConfigSpec.BooleanValue INSTABILITY_ENABLED;
     private static final ModConfigSpec.IntValue INSTABILITY_DIFFICULTY;
@@ -89,6 +91,21 @@ public final class RivencraftConfig {
         LINK_PANEL_INK_COST = builder.comment("Ink units consumed when preparing one baseline link-panel page.")
                 .defineInRange("link_panel_ink_cost", 2, 1, 16);
         builder.pop();
+        builder.push("random_pages");
+        RANDOM_PAGE_ALLOWLIST = builder.comment(
+                "Optional Page paths allowed in new random Ages and newly generated library loot.",
+                "The allowlist restricts only categories it mentions; unmentioned categories remain unrestricted.",
+                "Example: [\"sky/static\"] restricts random sky styles to Static Sky.",
+                "Full namespaced IDs are also accepted for compatibility.")
+                .defineList("allowlist", List.<String>of(), () -> "sky/static",
+                        RivencraftConfig::validPageId);
+        RANDOM_PAGE_BLOCKLIST = builder.comment(
+                "Page paths excluded from new random Ages and newly generated library loot.",
+                "The blocklist wins over the allowlist. Example: [\"sky/static\"].",
+                "Existing Ages and Pages deliberately remain usable in hand-authored books.")
+                .defineList("blocklist", List.<String>of(), () -> "sky/static",
+                        RivencraftConfig::validPageId);
+        builder.pop();
         builder.push("serene_seasons");
         AUTO_WHITELIST_SERENE_AGES = builder.comment(
                 "Automatically add Rivencraft Ages to Serene Seasons' dimension whitelist when loaded.",
@@ -233,6 +250,14 @@ public final class RivencraftConfig {
         return LINK_PANEL_INK_COST.get();
     }
 
+    public static List<? extends String> randomPageAllowlist() { return RANDOM_PAGE_ALLOWLIST.get(); }
+    public static List<? extends String> randomPageBlocklist() { return RANDOM_PAGE_BLOCKLIST.get(); }
+
+    private static boolean validPageId(Object value) {
+        return value instanceof String id && !id.isBlank()
+                && ResourceLocation.tryParse(id.contains(":") ? id : "rivencraft:" + id) != null;
+    }
+
     public static boolean autoWhitelistSereneAges() {
         return AUTO_WHITELIST_SERENE_AGES.get();
     }

src/main/java/net/dnorberg/rivencraft/gametest/LinkingGameTests.java

@@ -212,8 +212,10 @@ public final class LinkingGameTests {
                 "A page-free book must select a supported legacy-inspired terrain profile");
         helper.assertValueEqual(first.generationVersion(), AgeDefinition.CURRENT_GENERATION_VERSION,
                 "New Ages must record the current generation algorithm version");
-        helper.assertValueEqual(first.traits(), AgeTraits.select(first.seed()),
-                "A page-free book must persist the deterministic traits selected from its seed");
+        helper.assertValueEqual(first.traits(), net.dnorberg.rivencraft.book.AgeEnvironmentCompiler.forTerrain(
+                        AgeTraits.select(first.seed()),
+                        net.dnorberg.rivencraft.book.AgeRuntimeProfiles.resolve(first.generationProfile())),
+                "A page-free book must persist deterministic traits, with Cave sky/weather normalization");
         helper.assertTrue(first.traits().hasStoppedCelestialCycle()
                         || first.traits().celestialPeriod() >= AgeTraits.MIN_CELESTIAL_PERIOD
                         && first.traits().celestialPeriod() <= AgeTraits.MAX_CELESTIAL_PERIOD,

src/main/java/net/dnorberg/rivencraft/menu/BookBinderDiagnostics.java

@@ -0,0 +1,46 @@
+package net.dnorberg.rivencraft.menu;
+
+import net.minecraft.core.HolderLookup;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.util.datafix.DataFixTypes;
+import net.minecraft.world.level.saveddata.SavedData;
+
+/** World-persistent OP-only visibility switch for Book Binder writing diagnostics. */
+public final class BookBinderDiagnostics extends SavedData {
+    private static final String DATA_NAME = "rivencraft_binder_diagnostics";
+    private static final Factory<BookBinderDiagnostics> FACTORY = new Factory<>(
+            BookBinderDiagnostics::new, BookBinderDiagnostics::load, DataFixTypes.SAVED_DATA_MAP_DATA);
+    private boolean enabled;
+
+    public static BookBinderDiagnostics get(ServerLevel level) {
+        return level.getServer().overworld().getDataStorage().computeIfAbsent(FACTORY, DATA_NAME);
+    }
+
+    public boolean enabled() { return enabled; }
+
+    public boolean visibleTo(ServerPlayer player) {
+        return visibleTo(player.hasPermissions(2));
+    }
+
+    boolean visibleTo(boolean operator) { return enabled && operator; }
+
+    public boolean setEnabled(boolean enabled) {
+        if (this.enabled == enabled) return false;
+        this.enabled = enabled;
+        setDirty();
+        return true;
+    }
+
+    static BookBinderDiagnostics load(CompoundTag tag, HolderLookup.Provider registries) {
+        BookBinderDiagnostics data = new BookBinderDiagnostics();
+        data.enabled = tag.getBoolean("Enabled");
+        return data;
+    }
+
+    @Override public CompoundTag save(CompoundTag tag, HolderLookup.Provider registries) {
+        tag.putBoolean("Enabled", enabled);
+        return tag;
+    }
+}

src/main/java/net/dnorberg/rivencraft/menu/BookBinderDiagnosticsGameTests.java

@@ -0,0 +1,32 @@
+package net.dnorberg.rivencraft.menu;
+
+import net.dnorberg.rivencraft.Rivencraft;
+import net.minecraft.gametest.framework.GameTest;
+import net.minecraft.gametest.framework.GameTestHelper;
+import net.minecraft.nbt.CompoundTag;
+import net.neoforged.neoforge.gametest.GameTestHolder;
+import net.neoforged.neoforge.gametest.PrefixGameTestTemplate;
+
+/** Binder diagnostics are world-persistent but never visible to non-operators. */
+@GameTestHolder(Rivencraft.MOD_ID)
+@PrefixGameTestTemplate(false)
+public final class BookBinderDiagnosticsGameTests {
+    private BookBinderDiagnosticsGameTests() {}
+
+    @GameTest(template = "empty")
+    public static void binderMessagesDefaultOffAndPersist(GameTestHelper helper) {
+        BookBinderDiagnostics data = BookBinderDiagnostics.get(helper.getLevel());
+        helper.assertFalse(data.enabled(), "Binder diagnostic messages must default to off");
+        helper.assertTrue(data.setEnabled(true), "An OP toggle must change the world setting");
+        helper.assertFalse(data.setEnabled(true), "Repeating a toggle must not change the setting");
+        CompoundTag saved = data.save(new CompoundTag(), helper.getLevel().registryAccess());
+        BookBinderDiagnostics restored = BookBinderDiagnostics.load(saved, helper.getLevel().registryAccess());
+        helper.assertTrue(restored.enabled(), "The OP setting must survive world reload");
+        helper.assertTrue(restored.visibleTo(true), "An OP must see enabled binder diagnostics");
+        helper.assertFalse(restored.visibleTo(false), "A non-OP must not see enabled binder diagnostics");
+        helper.assertTrue(restored.setEnabled(false), "An OP toggle must disable messages");
+        helper.assertFalse(restored.visibleTo(true), "Disabled messages must be invisible even to OPs");
+        data.setEnabled(false);
+        helper.succeed();
+    }
+}

src/main/java/net/dnorberg/rivencraft/menu/BookBinderMenu.java

@@ -43,6 +43,7 @@ public final class BookBinderMenu extends AbstractContainerMenu {
     private int grammarErrorStripIndex = -1;
     private int grammarInstability;
     private int grammarIncompleteCount;
+    private int diagnosticsVisible;
     private WritingGrammar.Result serverGrammar;
 
     public BookBinderMenu(int id, Inventory inventory, RegistryFriendlyByteBuf data) {
@@ -62,34 +63,38 @@ public final class BookBinderMenu extends AbstractContainerMenu {
         });
         addDataSlot(new DataSlot() {
             @Override public int get() {
-                return clientSide || binder == null ? grammarErrorCode : binderDiagnostic()
+                return clientSide || binder == null ? grammarErrorCode : !diagnosticsVisibleToAuthor() ? -1 : binderDiagnostic()
                         .map(diagnostic -> diagnostic.code().ordinal()).orElse(-1);
             }
             @Override public void set(int value) { grammarErrorCode = value; }
         });
         addDataSlot(new DataSlot() {
             @Override public int get() {
-                return clientSide || binder == null ? grammarErrorStripIndex : binderDiagnostic()
+                return clientSide || binder == null ? grammarErrorStripIndex : !diagnosticsVisibleToAuthor() ? -1 : binderDiagnostic()
                         .map(diagnostic -> binder.writingStripIndex(diagnostic.index())).orElse(-1);
             }
             @Override public void set(int value) { grammarErrorStripIndex = value; }
         });
         addDataSlot(new DataSlot() {
             @Override public int get() {
-                return clientSide || binder == null ? grammarInstability
+                return clientSide || binder == null ? grammarInstability : !diagnosticsVisibleToAuthor() ? 0
                         : serverGrammar().writingInstability();
             }
             @Override public void set(int value) { grammarInstability = value; }
         });
         addDataSlot(new DataSlot() {
             @Override public int get() {
-                return clientSide || binder == null ? grammarIncompleteCount
+                return clientSide || binder == null ? grammarIncompleteCount : !diagnosticsVisibleToAuthor() ? 0
                         : (int) serverGrammar().diagnostics().stream()
                         .filter(diagnostic -> diagnostic.severity()
                                 == WritingGrammar.Severity.SEEDED_COMPLETION).count();
             }
             @Override public void set(int value) { grammarIncompleteCount = value; }
         });
+        addDataSlot(new DataSlot() {
+            @Override public int get() { return clientSide ? diagnosticsVisible : diagnosticsVisibleToAuthor() ? 1 : 0; }
+            @Override public void set(int value) { diagnosticsVisible = value; }
+        });
         addSlot(new BinderSlot(BookBinderBlockEntity.COVER, 8, 27, 64));
         addSlot(new BinderSlot(BookBinderBlockEntity.LINK_PANEL, -1000, -1000, 1));
         addSlot(new BinderSlot(BookBinderBlockEntity.NOTEBOOK, -1000, -1000, 1));
@@ -130,7 +135,12 @@ public final class BookBinderMenu extends AbstractContainerMenu {
     }
     public int grammarInstability() { return grammarInstability; }
     public int grammarIncompleteCount() { return grammarIncompleteCount; }
+    public boolean diagnosticsVisible() { return diagnosticsVisible != 0; }
     public int grammarErrorStripIndex() { return grammarErrorStripIndex; }
+    private boolean diagnosticsVisibleToAuthor() {
+        return bookAuthor instanceof ServerPlayer serverPlayer
+                && BookBinderDiagnostics.get(serverPlayer.serverLevel()).visibleTo(serverPlayer);
+    }
     public String title() { return binder == null ? "" : binder.title(); }
     public boolean setTitle(Player player, String title) {
         if (clientSide || !stillValid(player) || title == null

src/main/java/net/dnorberg/rivencraft/world/MystcraftLibraryFeature.java

@@ -4,6 +4,7 @@ import java.util.List;
 import java.util.Optional;
 import java.util.concurrent.ConcurrentHashMap;
 import net.dnorberg.rivencraft.config.RivencraftConfig;
+import net.dnorberg.rivencraft.book.RandomPagePolicy;
 import net.dnorberg.rivencraft.block.BookStandBlock;
 import net.dnorberg.rivencraft.block.entity.BookStandBlockEntity;
 import net.dnorberg.rivencraft.item.PageItem;
@@ -336,9 +337,17 @@ public final class MystcraftLibraryFeature {
 
     static List<ResourceLocation> symbolsForLoot(List<ResourceLocation> ageSymbols,
                                                  RivencraftConfig.LibraryLootMode mode) {
+        return symbolsForLoot(ageSymbols, mode, RandomPagePolicy.configured());
+    }
+
+    static List<ResourceLocation> symbolsForLoot(List<ResourceLocation> ageSymbols,
+                                                 RivencraftConfig.LibraryLootMode mode,
+                                                 RandomPagePolicy policy) {
         return mode == RivencraftConfig.LibraryLootMode.AGE_ONLY ? ageSymbols.stream()
+                .filter(policy::allows)
                 .filter(id -> SymbolCatalog.isKnown(new SymbolReference(id))).distinct().toList()
                 : SymbolCatalog.symbols().entrySet().stream()
+                .filter(entry -> policy.allows(entry.getKey()))
                 .filter(entry -> entry.getKey().getNamespace().equals("rivencraft")
                         && entry.getValue().semantics().isPresent()
                         && !entry.getKey().getPath().startsWith("block/")

src/main/java/net/dnorberg/rivencraft/world/MystcraftLibraryGameTests.java

@@ -2,6 +2,7 @@ package net.dnorberg.rivencraft.world;
 
 import java.util.List;
 import net.dnorberg.rivencraft.config.RivencraftConfig;
+import net.dnorberg.rivencraft.book.RandomPagePolicy;
 import net.dnorberg.rivencraft.block.BookStandBlock;
 import net.dnorberg.rivencraft.block.entity.BookStandBlockEntity;
 import net.dnorberg.rivencraft.item.PageItem;
@@ -107,6 +108,85 @@ public final class MystcraftLibraryGameTests {
         helper.succeed();
     }
 
+    @GameTest(template = "empty")
+    public static void pageListsFilterRandomChoicesAndLibraryLoot(GameTestHelper helper) {
+        ResourceLocation staticSky = ResourceLocation.parse("rivencraft:sky/static");
+        ResourceLocation netherSky = ResourceLocation.parse("rivencraft:sky/nether");
+        ResourceLocation rocks = ResourceLocation.parse("rivencraft:feature/rocks");
+        helper.assertValueEqual(RandomPagePolicy.parsePageId("sky/static"), staticSky,
+                "A shorthand Page path must resolve to Rivencraft's namespace");
+        helper.assertValueEqual(RandomPagePolicy.parsePageId("rivencraft:sky/static"), staticSky,
+                "An existing fully qualified Page ID must still work");
+        RandomPagePolicy policy = new RandomPagePolicy(java.util.Set.of(staticSky, netherSky),
+                java.util.Set.of(netherSky, rocks));
+        helper.assertTrue(policy.allows(staticSky), "Allowlisted sky Page must remain available");
+        helper.assertTrue(!policy.allows(netherSky), "Blocklist must override allowlist");
+        helper.assertTrue(!policy.allows(rocks), "Blocked feature Page must be excluded");
+        helper.assertTrue(policy.allows(ResourceLocation.parse("rivencraft:terrain/standard")),
+                "Unmentioned categories must remain unrestricted");
+        RandomPagePolicy biomeController = new RandomPagePolicy(
+                java.util.Set.of(ResourceLocation.parse("rivencraft:biome/tiny")), java.util.Set.of());
+        helper.assertTrue(biomeController.allows(ResourceLocation.parse("rivencraft:biome/plains")),
+                "A biome-controller allowlist must not exclude actual biome Pages");
+        helper.assertTrue(!biomeController.allows(ResourceLocation.parse("rivencraft:biome/huge")),
+                "A biome-controller allowlist must constrain other distributions");
+        helper.assertValueEqual(RandomPagePolicy.load(policy.save()), policy,
+                "Random Age Page policy must survive save and reload");
+        helper.assertValueEqual(MystcraftLibraryFeature.symbolsForLoot(
+                        List.of(staticSky, netherSky, rocks), RivencraftConfig.LibraryLootMode.AGE_ONLY, policy),
+                List.of(staticSky), "Age-only library loot must exclude blocked Pages");
+        for (long seed = 0; seed < 100; seed++) {
+            helper.assertValueEqual(net.dnorberg.rivencraft.book.AgeSkyProfile.random(seed,
+                            net.dnorberg.rivencraft.book.AgeTraits.select(seed), policy).style(),
+                    net.dnorberg.rivencraft.book.AgeSkyProfile.Style.STATIC,
+                    "Sky allowlist must constrain new random Ages");
+        }
+        RandomPagePolicy singleTerrain = new RandomPagePolicy(
+                java.util.Set.of(ResourceLocation.parse("rivencraft:terrain/standard"),
+                        ResourceLocation.parse("rivencraft:lighting/normal")), java.util.Set.of());
+        for (long seed = 0; seed < 100; seed++) {
+            helper.assertValueEqual(net.dnorberg.rivencraft.book.AgeRuntimeProfiles.select(seed, singleTerrain),
+                    ResourceLocation.parse("rivencraft:standard"),
+                    "Random terrain must honor a category allowlist");
+            helper.assertValueEqual(net.dnorberg.rivencraft.book.AgeTraits.select(seed, singleTerrain).lighting(),
+                    net.dnorberg.rivencraft.book.AgeTraits.Lighting.NORMAL,
+                    "Random lighting must honor a category allowlist");
+        }
+        RandomPagePolicy noRequiredPages = new RandomPagePolicy(java.util.Set.of(
+                ResourceLocation.parse("rivencraft:terrain/not_present"),
+                ResourceLocation.parse("rivencraft:lighting/not_present"),
+                ResourceLocation.parse("rivencraft:weather/not_present"),
+                ResourceLocation.parse("rivencraft:sky/not_present"),
+                ResourceLocation.parse("rivencraft:season/not_present")), java.util.Set.of());
+        helper.assertValueEqual(net.dnorberg.rivencraft.book.AgeRuntimeProfiles.select(42L, noRequiredPages),
+                ResourceLocation.parse("rivencraft:standard"), "Empty terrain family must use Standard");
+        var fallbackTraits = net.dnorberg.rivencraft.book.AgeTraits.select(42L, noRequiredPages);
+        helper.assertValueEqual(fallbackTraits.lighting(),
+                net.dnorberg.rivencraft.book.AgeTraits.Lighting.NORMAL,
+                "Empty lighting family must use Normal");
+        helper.assertValueEqual(fallbackTraits.weather(),
+                net.dnorberg.rivencraft.book.AgeTraits.Weather.NORMAL,
+                "Empty weather family must use Normal");
+        helper.assertValueEqual(net.dnorberg.rivencraft.book.AgeSkyProfile.random(42L,
+                        fallbackTraits, noRequiredPages).style(),
+                net.dnorberg.rivencraft.book.AgeSkyProfile.Style.INHERITED,
+                "Empty sky family must use inherited sky");
+        helper.assertValueEqual(net.dnorberg.rivencraft.book.AgeSeasonMode.select(null, 42L,
+                        true, null, noRequiredPages),
+                net.dnorberg.rivencraft.book.AgeSeasonMode.NO_SEASONS,
+                "Empty season family must use No Seasons");
+        var blockedControllers = java.util.Arrays.stream(
+                        net.dnorberg.rivencraft.book.AgeTraits.BiomeDistribution.values())
+                .map(value -> ResourceLocation.parse("rivencraft:biome/"
+                        + value.name().toLowerCase(java.util.Locale.ROOT)))
+                .collect(java.util.stream.Collectors.toUnmodifiableSet());
+        helper.assertValueEqual(net.dnorberg.rivencraft.book.AgeTraits.select(42L,
+                        new RandomPagePolicy(java.util.Set.of(), blockedControllers)).biomeDistribution(),
+                net.dnorberg.rivencraft.book.AgeTraits.BiomeDistribution.NATIVE,
+                "Empty biome-distribution family must use Native");
+        helper.succeed();
+    }
+
     @GameTest(template = "empty")
     public static void testSpacingIsSessionOnlyAndKeepsLegacySites(GameTestHelper helper) {
         long seed = 881L;

src/main/java/net/dnorberg/rivencraft/writing/WritingGrammar.java

@@ -191,7 +191,8 @@ public final class WritingGrammar {
 
     private static boolean numberTarget(Role role) {
         return role == Role.COLOR || role == Role.PERIOD_MODIFIER
-                || role == Role.ANGLE_MODIFIER || role == Role.PHASE_MODIFIER;
+                || role == Role.ANGLE_MODIFIER || role == Role.PHASE_MODIFIER
+                || role == Role.SIZE_MODIFIER;
     }
 
     private static int stage(Role role) {

src/main/resources/assets/rivencraft/lang/en_us.json

@@ -260,7 +260,7 @@
   "symbol.rivencraft.number.22": "D'ni 22",
   "symbol.rivencraft.number.23": "D'ni 23",
   "symbol.rivencraft.number.24": "D'ni 24",
-  "symbol.rivencraft.number.description": "Set the next color page to this number × 10, Angle or Phase to × 15°, or Length to × 0.08. A number page affects only the immediately following page.",
+  "symbol.rivencraft.number.description": "Set the next color page to this number × 10, Angle or Phase to × 15°, Length to × 0.08, or Celestial Size from 0.25× to 3×. A number page affects only the immediately following page.",
   "symbol.rivencraft.weather.normal": "Normal Weather",
   "symbol.rivencraft.weather.normal.description": "Use the normal weather cycle.",
   "symbol.rivencraft.weather.fast": "Fast Weather",