diff --git a/src/simulator/crates/mc-ai/src/evaluator.rs b/src/simulator/crates/mc-ai/src/evaluator.rs
index e1cd6325..6f669804 100644
--- a/src/simulator/crates/mc-ai/src/evaluator.rs
+++ b/src/simulator/crates/mc-ai/src/evaluator.rs
@@ -1,330 +1,17 @@
 use std::collections::HashMap;
-use std::path::{Path, PathBuf};
-
-use serde::Deserialize;
-use thiserror::Error;
+use std::path::Path;
 
 use crate::game_state::{
     AiCityState, AiFormationState, AiPlayerState, AiProductionCandidate, AiTechCandidate,
     StrategicWeights,
 };
 
-/// Errors produced when resolving a clan personality into scoring weights.
-#[derive(Debug, Error)]
-pub enum LoadError {
-    #[error("failed to read ai_personalities.json at {path}: {source}")]
-    Io {
-        path: PathBuf,
-        #[source]
-        source: std::io::Error,
-    },
-    #[error("failed to parse ai_personalities.json at {path}: {source}")]
-    Parse {
-        path: PathBuf,
-        #[source]
-        source: serde_json::Error,
-    },
-    #[error("unknown clan personality id: {0}")]
-    UnknownClan(String),
-}
+// p2-65 Phase 0b — moved to mc-core. Re-exported here so existing
+// `mc_ai::evaluator::{LoadError, PersonalityDef, ScoringWeights}` callers
+// (~12 sites across mc-balance, mc-sim, mc-turn, mc-ecology and tests)
+// keep compiling without an import sweep.
+pub use mc_core::scoring_weights::{LoadError, PersonalityDef, ScoringWeights};
 
-/// Shape of one entry in `public/games/age-of-dwarves/data/ai_personalities.json`.
-/// Only the fields the evaluator consumes are decoded; unknown fields are ignored.
-#[derive(Debug, Clone, Deserialize)]
-pub struct PersonalityDef {
-    #[serde(default)]
-    pub id: String,
-    #[serde(default)]
-    pub name: String,
-    #[serde(default)]
-    pub strategic_axes: HashMap<String, i32>,
-    /// p2-55 Wave 2 — capture-posture scoring scalar (`PersonalityPriors::capture_weight`).
-    /// Top-level on the personality record (sibling of `strategic_axes`); `None`
-    /// means the loader uses the neutral default.
-    #[serde(default)]
-    pub capture_weight: Option<f32>,
-    /// p2-55 Wave 2 — ransom acceptance probability scalar.
-    #[serde(default)]
-    pub ransom_accept_threshold: Option<f32>,
-    /// p2-55 Wave 2 — multiplier on the destroy-posture denial-value score.
-    #[serde(default)]
-    pub destroy_civilian_aggression: Option<f32>,
-    /// p2-44 — Offense-category promotion weight (`PersonalityPriors::promotion_offense_weight`).
-    /// `None` means the loader uses the neutral default (1.0).
-    #[serde(default)]
-    pub promotion_offense_weight: Option<f32>,
-    /// p2-44 — Defense-category promotion weight.
-    #[serde(default)]
-    pub promotion_defense_weight: Option<f32>,
-    /// p2-44 — Mobility / utility promotion weight.
-    #[serde(default)]
-    pub promotion_mobility_weight: Option<f32>,
-}
-
-/// All tunable scoring constants — the optimizer target for CMA-ES.
-///
-/// Effect-based weights replace the old per-building-ID weights (granary_base, etc.).
-/// This means new buildings/units added to JSON get reasonable scores automatically
-/// without Rust code changes.
-#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
-#[serde(default)]
-pub struct ScoringWeights {
-    // ── City site scoring (used by CitySiteScorer in GDScript) ──────────────
-    pub site_food: f32,
-    pub site_prod: f32,
-    pub site_gold: f32,
-    pub site_quality: f32,
-    pub site_resource: f32,
-
-    // ── Effect-based building scoring ────────────────────────────────────────
-    pub effect_food: f32,
-    pub effect_prod: f32,
-    pub effect_gold: f32,
-    pub effect_science: f32,
-    pub effect_culture: f32,
-    pub effect_defense: f32,
-    pub food_deficit_bonus: f32,
-
-    // ── Unit scoring ─────────────────────────────────────────────────────────
-    pub military_base: f32,
-    pub military_threat_scale: f32,
-    pub military_melee_need: f32,
-    pub military_ranged_need: f32,
-    pub military_flying_need: f32,
-
-    // ── Expansion ────────────────────────────────────────────────────────────
-    pub expansion_base: f32,
-    pub expansion_diminish_rate: f32,
-    pub expansion_econ_threshold: f32,
-
-    // ── State evaluation (MCTS leaf evaluator) ───────────────────────────────
-    pub yield_food: f32,
-    pub yield_prod: f32,
-    pub yield_gold: f32,
-    pub yield_science: f32,
-    pub yield_culture: f32,
-    pub pop_value: f32,
-    pub city_expansion: f32,
-    pub threat_penalty: f32,
-}
-
-impl Default for ScoringWeights {
-    fn default() -> Self {
-        Self {
-            site_food: 3.0,
-            site_prod: 2.5,
-            site_gold: 1.5,
-            site_quality: 2.0,
-            site_resource: 3.5,
-            effect_food: 0.7,
-            effect_prod: 0.5,
-            effect_gold: 0.4,
-            effect_science: 0.45,
-            effect_culture: 0.35,
-            effect_defense: 0.7,
-            food_deficit_bonus: 0.6,
-            military_base: 0.55,
-            military_threat_scale: 1.0,
-            military_melee_need: 0.6,
-            military_ranged_need: 0.5,
-            military_flying_need: 0.4,
-            expansion_base: 0.5,
-            expansion_diminish_rate: 0.3,
-            expansion_econ_threshold: 30.0,
-            yield_food: 1.5,
-            yield_prod: 2.0,
-            yield_gold: 1.0,
-            yield_science: 1.2,
-            yield_culture: 0.8,
-            pop_value: 2.0,
-            city_expansion: 5.0,
-            threat_penalty: 8.0,
-        }
-    }
-}
-
-impl ScoringWeights {
-    /// Number of tunable parameters — dimensionality for CMA-ES.
-    pub const N: usize = 28;
-
-    /// Baseline weights — alias for `Self::default()`, used as the starting
-    /// point before per-clan axis deltas are applied.
-    pub fn baseline() -> Self {
-        Self::default()
-    }
-
-    /// Load scoring weights for a specific clan personality from
-    /// `<data_dir>/ai_personalities.json`. Applies the six-axis delta mapping
-    /// defined in `apply_axes` to the baseline weights.
-    ///
-    /// Errors:
-    /// - `LoadError::Io` if the file is missing or unreadable
-    /// - `LoadError::Parse` if the JSON is malformed
-    /// - `LoadError::UnknownClan` if `id` is not a key in the file
-    pub fn from_personality(id: &str, data_dir: &Path) -> Result<Self, LoadError> {
-        let path = data_dir.join("ai_personalities.json");
-        let json = std::fs::read_to_string(&path).map_err(|source| LoadError::Io {
-            path: path.clone(),
-            source,
-        })?;
-        Self::from_personality_json(id, &json)
-    }
-
-    /// Same as `from_personality` but takes the JSON string directly. Use this
-    /// from contexts where the file lives inside a Godot .pck and `std::fs`
-    /// cannot reach it (any packed export — macOS .app, Linux binary, Windows
-    /// .exe). The GDScript caller reads the file via `FileAccess` and hands the
-    /// string in. p1-24.
-    pub fn from_personality_json(id: &str, json: &str) -> Result<Self, LoadError> {
-        let personalities: HashMap<String, PersonalityDef> =
-            serde_json::from_str(json).map_err(|source| LoadError::Parse {
-                path: PathBuf::from("<inline-json>"),
-                source,
-            })?;
-        let p = personalities
-            .get(id)
-            .ok_or_else(|| LoadError::UnknownClan(id.to_string()))?;
-        let mut weights = Self::baseline();
-        weights.apply_axes(&p.strategic_axes);
-        Ok(weights)
-    }
-
-    /// Mutate this weight set to reflect clan personality axes.
-    ///
-    /// Axes are read on the JSON 1..=10 scale where 5 is neutral; each knob is
-    /// scaled by `1 + K · (axis - 5)` for positive-direction pushes or
-    /// `1 - K · (axis - 5)` where the axis should reduce the knob. The
-    /// multiplier is clamped to `[0.25, 2.5]` so an extreme axis can't zero a
-    /// weight out nor balloon it past the optimizer's search bounds.
-    ///
-    /// Mapping follows the Task B1 plan:
-    /// - `aggression` → military base/need/threat-scale (+), threat_penalty (−)
-    /// - `expansion` → expansion_base / site_food / site_resource (+),
-    ///   expansion_diminish_rate (−)
-    /// - `production` → site_prod / effect_prod / yield_prod (+)
-    /// - `wealth` → site_gold / effect_gold / yield_gold (+)
-    /// - `trade_willingness` → effect_gold mild (+) (gold infra more valued when
-    ///   trade is a posture; diplomacy hooks owned by Task B3)
-    /// - `grudge_persistence` → threat_penalty (−) (high-grudge clans stay in
-    ///   fights rather than backing off under threat; diplomacy hooks owned by
-    ///   Task B3)
-    pub fn apply_axes(&mut self, axes: &HashMap<String, i32>) {
-        let a = |key: &str| -> f32 { axis_delta(axes, key) };
-
-        let aggression = a("aggression");
-        let expansion = a("expansion");
-        let production = a("production");
-        let wealth = a("wealth");
-        let trade = a("trade_willingness");
-        let grudge = a("grudge_persistence");
-
-        // ── Aggression ──────────────────────────────────────────────────────
-        scale(&mut self.military_base, 1.0 + 0.15 * aggression);
-        scale(&mut self.military_threat_scale, 1.0 + 0.15 * aggression);
-        scale(&mut self.military_melee_need, 1.0 + 0.12 * aggression);
-        scale(&mut self.military_ranged_need, 1.0 + 0.10 * aggression);
-        // Belligerent clans tolerate more threat → smaller threat_penalty.
-        scale(&mut self.threat_penalty, 1.0 - 0.08 * aggression);
-
-        // ── Expansion ───────────────────────────────────────────────────────
-        scale(&mut self.expansion_base, 1.0 + 0.20 * expansion);
-        scale(&mut self.site_food, 1.0 + 0.10 * expansion);
-        scale(&mut self.site_resource, 1.0 + 0.10 * expansion);
-        // Tall clans (low expansion) feel the diminishing-returns penalty more
-        // strongly — high expansion clans feel it less.
-        scale(&mut self.expansion_diminish_rate, 1.0 - 0.15 * expansion);
-
-        // ── Production ──────────────────────────────────────────────────────
-        scale(&mut self.site_prod, 1.0 + 0.15 * production);
-        scale(&mut self.effect_prod, 1.0 + 0.18 * production);
-        scale(&mut self.yield_prod, 1.0 + 0.15 * production);
-
-        // ── Wealth ──────────────────────────────────────────────────────────
-        scale(&mut self.site_gold, 1.0 + 0.15 * wealth);
-        scale(&mut self.effect_gold, 1.0 + 0.18 * wealth);
-        scale(&mut self.yield_gold, 1.0 + 0.15 * wealth);
-
-        // ── Trade willingness ───────────────────────────────────────────────
-        // Mercantile postures value gold-producing infrastructure a bit more;
-        // full diplomacy plumbing is Task B3's scope.
-        scale(&mut self.effect_gold, 1.0 + 0.06 * trade);
-
-        // ── Grudge persistence ──────────────────────────────────────────────
-        // High-grudge clans keep fighting under pressure instead of retreating,
-        // so the threat_penalty shrinks (they care less about staying safe).
-        scale(&mut self.threat_penalty, 1.0 - 0.06 * grudge);
-    }
-
-    /// Serialize to a flat Vec for CMA-ES. Order must match `from_vec`.
-    pub fn to_vec(&self) -> Vec<f64> {
-        vec![
-            f64::from(self.site_food),
-            f64::from(self.site_prod),
-            f64::from(self.site_gold),
-            f64::from(self.site_quality),
-            f64::from(self.site_resource),
-            f64::from(self.effect_food),
-            f64::from(self.effect_prod),
-            f64::from(self.effect_gold),
-            f64::from(self.effect_science),
-            f64::from(self.effect_culture),
-            f64::from(self.effect_defense),
-            f64::from(self.food_deficit_bonus),
-            f64::from(self.military_base),
-            f64::from(self.military_threat_scale),
-            f64::from(self.military_melee_need),
-            f64::from(self.military_ranged_need),
-            f64::from(self.military_flying_need),
-            f64::from(self.expansion_base),
-            f64::from(self.expansion_diminish_rate),
-            f64::from(self.expansion_econ_threshold),
-            f64::from(self.yield_food),
-            f64::from(self.yield_prod),
-            f64::from(self.yield_gold),
-            f64::from(self.yield_science),
-            f64::from(self.yield_culture),
-            f64::from(self.pop_value),
-            f64::from(self.city_expansion),
-            f64::from(self.threat_penalty),
-        ]
-    }
-
-    /// Deserialize from a flat Vec. Values are clamped to sane ranges.
-    pub fn from_vec(v: &[f64]) -> Self {
-        assert!(v.len() >= Self::N, "weight vector too short");
-        let pos = |x: f64| x.max(0.01) as f32;
-        Self {
-            site_food: pos(v[0]),
-            site_prod: pos(v[1]),
-            site_gold: pos(v[2]),
-            site_quality: pos(v[3]),
-            site_resource: pos(v[4]),
-            effect_food: pos(v[5]),
-            effect_prod: pos(v[6]),
-            effect_gold: pos(v[7]),
-            effect_science: pos(v[8]),
-            effect_culture: pos(v[9]),
-            effect_defense: pos(v[10]),
-            food_deficit_bonus: pos(v[11]),
-            military_base: pos(v[12]),
-            military_threat_scale: pos(v[13]),
-            military_melee_need: pos(v[14]),
-            military_ranged_need: pos(v[15]),
-            military_flying_need: pos(v[16]),
-            expansion_base: pos(v[17]),
-            expansion_diminish_rate: pos(v[18]),
-            expansion_econ_threshold: pos(v[19]),
-            yield_food: pos(v[20]),
-            yield_prod: pos(v[21]),
-            yield_gold: pos(v[22]),
-            yield_science: pos(v[23]),
-            yield_culture: pos(v[24]),
-            pop_value: pos(v[25]),
-            city_expansion: pos(v[26]),
-            threat_penalty: pos(v[27]),
-        }
-    }
-}
 
 /// Scores a candidate action or overall game state.
 pub trait AiEvaluator: Send + Sync {
@@ -971,22 +658,10 @@ fn nearest_hex(
     })
 }
 
-/// Read a strategic axis (1..=10 JSON scale) and return its neutral-centered
-/// delta as an `f32`. Missing axes default to 5 (neutral) so a partial JSON
-/// entry degrades gracefully instead of producing an extreme clan.
-fn axis_delta(axes: &HashMap<String, i32>, key: &str) -> f32 {
-    let raw = *axes.get(key).unwrap_or(&5);
-    let clamped = raw.clamp(1, 10);
-    (clamped as f32) - 5.0
-}
-
-/// Multiply a weight by `factor`, clamping the result to `[0.25x, 2.5x]` of
-/// the pre-scaled value so extreme axes can't zero out or blow up a knob
-/// past what CMA-ES expects to search over.
-fn scale(weight: &mut f32, factor: f32) {
-    let clamped = factor.clamp(0.25, 2.5);
-    *weight *= clamped;
-}
+// p2-65 Phase 0b — `axis_delta` and `scale` helpers moved to
+// `mc_core::scoring_weights` alongside `ScoringWeights::apply_axes`.
+// `StrategicWeights::from_axes_1to10` below uses its own local `norm`
+// closure (different scaling) so it does not need either helper.
 
 impl StrategicWeights {
     /// Load strategic weights for a clan from `<data_dir>/ai_personalities.json`.
diff --git a/src/simulator/crates/mc-core/Cargo.toml b/src/simulator/crates/mc-core/Cargo.toml
index 47ec109a..3da7193a 100644
--- a/src/simulator/crates/mc-core/Cargo.toml
+++ b/src/simulator/crates/mc-core/Cargo.toml
@@ -9,6 +9,7 @@ serde_json.workspace = true
 getrandom.workspace  = true
 siphasher.workspace  = true
 rayon                = "1"
+thiserror            = "1"
 
 [lints]
 workspace = true
diff --git a/src/simulator/crates/mc-core/src/lib.rs b/src/simulator/crates/mc-core/src/lib.rs
index 2fff7787..1cb1d79f 100644
--- a/src/simulator/crates/mc-core/src/lib.rs
+++ b/src/simulator/crates/mc-core/src/lib.rs
@@ -24,6 +24,7 @@ pub mod perf;
 pub mod player;
 pub mod production_origin;
 pub mod resources;
+pub mod scoring_weights;
 pub mod seed;
 pub mod tech;
 pub mod units;
@@ -45,6 +46,7 @@ pub use derived_stats::{DerivedStats, InequalityStat};
 pub use ids::{BuildingId, GreatPersonClass, HarvestPolicyId, ResourceId, SpecialistId, SpeciesId, StackMode, UnitId};
 pub use lair::{LairCombatMode, LairId, SiegeOutcome, SiegePressure, SiegeState};
 pub use resources::{ResourceKind, ResourceStockpile, StockpileError as ResourceStockpileError};
+pub use scoring_weights::{LoadError, PersonalityDef, ScoringWeights};
 pub use player::{HexCoord, PlayerPrologue};
 pub use production_origin::ProductionOrigin;
 pub use tech::TechDomain;
diff --git a/src/simulator/crates/mc-core/src/scoring_weights.rs b/src/simulator/crates/mc-core/src/scoring_weights.rs
new file mode 100644
index 00000000..555657f8
--- /dev/null
+++ b/src/simulator/crates/mc-core/src/scoring_weights.rs
@@ -0,0 +1,365 @@
+//! Tunable scoring weights + clan-personality loader. Single source of truth.
+//!
+//! Hosted in `mc-core` (rather than `mc-ai`) because both `mc-ai`
+//! (heuristic evaluator) and `mc-turn` / `mc-balance` / `mc-sim` (consumers
+//! that need to construct or pass-through a `GameState.scoring_weights`)
+//! reference the same struct. Putting it on the leaf crate avoids the
+//! reverse-direction dep where mc-turn imports mc-ai purely for one field
+//! shape.
+//!
+//! Items moved from `mc-ai::evaluator` (p2-65 Phase 0b):
+//! - `LoadError` — typed errors from the personality JSON loader.
+//! - `PersonalityDef` — JSON-decoded shape of one entry in
+//!   `public/games/age-of-dwarves/data/ai_personalities.json`.
+//! - `ScoringWeights` — 28-dimensional weight vector with `default`,
+//!   `baseline`, `from_personality`, `from_personality_json`, `apply_axes`,
+//!   `to_vec`, `from_vec`. The CMA-ES optimizer target.
+//! - Private helpers `axis_delta`, `scale` used only by `apply_axes`.
+
+use std::collections::HashMap;
+use std::path::{Path, PathBuf};
+
+use serde::Deserialize;
+use thiserror::Error;
+
+/// Errors produced when resolving a clan personality into scoring weights.
+#[derive(Debug, Error)]
+pub enum LoadError {
+    /// Failed to read the personality JSON file from disk.
+    #[error("failed to read ai_personalities.json at {path}: {source}")]
+    Io {
+        /// Path that the loader attempted to open.
+        path: PathBuf,
+        /// Underlying I/O error.
+        #[source]
+        source: std::io::Error,
+    },
+    /// JSON failed to parse into the expected `HashMap<String, PersonalityDef>`.
+    #[error("failed to parse ai_personalities.json at {path}: {source}")]
+    Parse {
+        /// Path that produced the malformed JSON.
+        path: PathBuf,
+        /// Underlying serde error.
+        #[source]
+        source: serde_json::Error,
+    },
+    /// JSON parsed cleanly but did not contain the requested clan id.
+    #[error("unknown clan personality id: {0}")]
+    UnknownClan(String),
+}
+
+/// Shape of one entry in `public/games/age-of-dwarves/data/ai_personalities.json`.
+/// Only the fields the evaluator + policy priors consume are decoded; unknown
+/// fields are ignored.
+#[derive(Debug, Clone, Deserialize)]
+pub struct PersonalityDef {
+    /// Stable id (matches the JSON key).
+    #[serde(default)]
+    pub id: String,
+    /// Display name.
+    #[serde(default)]
+    pub name: String,
+    /// Six raw axes on the 1..=10 scale (`aggression`, `expansion`,
+    /// `production`, `wealth`, `trade_willingness`, `grudge_persistence`).
+    #[serde(default)]
+    pub strategic_axes: HashMap<String, i32>,
+    /// p2-55 Wave 2 — capture-posture scoring scalar (`PersonalityPriors::capture_weight`).
+    /// Top-level on the personality record (sibling of `strategic_axes`); `None`
+    /// means the loader uses the neutral default.
+    #[serde(default)]
+    pub capture_weight: Option<f32>,
+    /// p2-55 Wave 2 — ransom acceptance probability scalar.
+    #[serde(default)]
+    pub ransom_accept_threshold: Option<f32>,
+    /// p2-55 Wave 2 — multiplier on the destroy-posture denial-value score.
+    #[serde(default)]
+    pub destroy_civilian_aggression: Option<f32>,
+    /// p2-44 — Offense-category promotion weight (`PersonalityPriors::promotion_offense_weight`).
+    /// `None` means the loader uses the neutral default (1.0).
+    #[serde(default)]
+    pub promotion_offense_weight: Option<f32>,
+    /// p2-44 — Defense-category promotion weight.
+    #[serde(default)]
+    pub promotion_defense_weight: Option<f32>,
+    /// p2-44 — Mobility / utility promotion weight.
+    #[serde(default)]
+    pub promotion_mobility_weight: Option<f32>,
+}
+
+/// All tunable scoring constants — the optimizer target for CMA-ES.
+///
+/// Effect-based weights replace the old per-building-ID weights (granary_base, etc.).
+/// This means new buildings/units added to JSON get reasonable scores automatically
+/// without Rust code changes.
+#[allow(missing_docs)] // 28 self-describing field names; comments in original source.
+#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
+#[serde(default)]
+pub struct ScoringWeights {
+    // ── City site scoring (used by CitySiteScorer in GDScript) ──────────────
+    pub site_food: f32,
+    pub site_prod: f32,
+    pub site_gold: f32,
+    pub site_quality: f32,
+    pub site_resource: f32,
+
+    // ── Effect-based building scoring ────────────────────────────────────────
+    pub effect_food: f32,
+    pub effect_prod: f32,
+    pub effect_gold: f32,
+    pub effect_science: f32,
+    pub effect_culture: f32,
+    pub effect_defense: f32,
+    pub food_deficit_bonus: f32,
+
+    // ── Unit scoring ─────────────────────────────────────────────────────────
+    pub military_base: f32,
+    pub military_threat_scale: f32,
+    pub military_melee_need: f32,
+    pub military_ranged_need: f32,
+    pub military_flying_need: f32,
+
+    // ── Expansion ────────────────────────────────────────────────────────────
+    pub expansion_base: f32,
+    pub expansion_diminish_rate: f32,
+    pub expansion_econ_threshold: f32,
+
+    // ── State evaluation (MCTS leaf evaluator) ───────────────────────────────
+    pub yield_food: f32,
+    pub yield_prod: f32,
+    pub yield_gold: f32,
+    pub yield_science: f32,
+    pub yield_culture: f32,
+    pub pop_value: f32,
+    pub city_expansion: f32,
+    pub threat_penalty: f32,
+}
+
+impl Default for ScoringWeights {
+    fn default() -> Self {
+        Self {
+            site_food: 3.0,
+            site_prod: 2.5,
+            site_gold: 1.5,
+            site_quality: 2.0,
+            site_resource: 3.5,
+            effect_food: 0.7,
+            effect_prod: 0.5,
+            effect_gold: 0.4,
+            effect_science: 0.45,
+            effect_culture: 0.35,
+            effect_defense: 0.7,
+            food_deficit_bonus: 0.6,
+            military_base: 0.55,
+            military_threat_scale: 1.0,
+            military_melee_need: 0.6,
+            military_ranged_need: 0.5,
+            military_flying_need: 0.4,
+            expansion_base: 0.5,
+            expansion_diminish_rate: 0.3,
+            expansion_econ_threshold: 30.0,
+            yield_food: 1.5,
+            yield_prod: 2.0,
+            yield_gold: 1.0,
+            yield_science: 1.2,
+            yield_culture: 0.8,
+            pop_value: 2.0,
+            city_expansion: 5.0,
+            threat_penalty: 8.0,
+        }
+    }
+}
+
+impl ScoringWeights {
+    /// Number of tunable parameters — dimensionality for CMA-ES.
+    pub const N: usize = 28;
+
+    /// Baseline weights — alias for `Self::default()`, used as the starting
+    /// point before per-clan axis deltas are applied.
+    pub fn baseline() -> Self {
+        Self::default()
+    }
+
+    /// Load scoring weights for a specific clan personality from
+    /// `<data_dir>/ai_personalities.json`. Applies the six-axis delta mapping
+    /// defined in `apply_axes` to the baseline weights.
+    ///
+    /// Errors:
+    /// - `LoadError::Io` if the file is missing or unreadable
+    /// - `LoadError::Parse` if the JSON is malformed
+    /// - `LoadError::UnknownClan` if `id` is not a key in the file
+    pub fn from_personality(id: &str, data_dir: &Path) -> Result<Self, LoadError> {
+        let path = data_dir.join("ai_personalities.json");
+        let json = std::fs::read_to_string(&path).map_err(|source| LoadError::Io {
+            path: path.clone(),
+            source,
+        })?;
+        Self::from_personality_json(id, &json)
+    }
+
+    /// Same as `from_personality` but takes the JSON string directly. Use this
+    /// from contexts where the file lives inside a Godot .pck and `std::fs`
+    /// cannot reach it (any packed export — macOS .app, Linux binary, Windows
+    /// .exe). The GDScript caller reads the file via `FileAccess` and hands the
+    /// string in. p1-24.
+    pub fn from_personality_json(id: &str, json: &str) -> Result<Self, LoadError> {
+        let personalities: HashMap<String, PersonalityDef> =
+            serde_json::from_str(json).map_err(|source| LoadError::Parse {
+                path: PathBuf::from("<inline-json>"),
+                source,
+            })?;
+        let p = personalities
+            .get(id)
+            .ok_or_else(|| LoadError::UnknownClan(id.to_string()))?;
+        let mut weights = Self::baseline();
+        weights.apply_axes(&p.strategic_axes);
+        Ok(weights)
+    }
+
+    /// Mutate this weight set to reflect clan personality axes.
+    ///
+    /// Axes are read on the JSON 1..=10 scale where 5 is neutral; each knob is
+    /// scaled by `1 + K · (axis - 5)` for positive-direction pushes or
+    /// `1 - K · (axis - 5)` where the axis should reduce the knob. The
+    /// multiplier is clamped to `[0.25, 2.5]` so an extreme axis can't zero a
+    /// weight out nor balloon it past the optimizer's search bounds.
+    ///
+    /// Mapping follows the Task B1 plan:
+    /// - `aggression` → military base/need/threat-scale (+), threat_penalty (−)
+    /// - `expansion` → expansion_base / site_food / site_resource (+),
+    ///   expansion_diminish_rate (−)
+    /// - `production` → site_prod / effect_prod / yield_prod (+)
+    /// - `wealth` → site_gold / effect_gold / yield_gold (+)
+    /// - `trade_willingness` → effect_gold mild (+) (gold infra more valued when
+    ///   trade is a posture; diplomacy hooks owned by Task B3)
+    /// - `grudge_persistence` → threat_penalty (−) (high-grudge clans stay in
+    ///   fights rather than backing off under threat; diplomacy hooks owned by
+    ///   Task B3)
+    pub fn apply_axes(&mut self, axes: &HashMap<String, i32>) {
+        let a = |key: &str| -> f32 { axis_delta(axes, key) };
+
+        let aggression = a("aggression");
+        let expansion = a("expansion");
+        let production = a("production");
+        let wealth = a("wealth");
+        let trade = a("trade_willingness");
+        let grudge = a("grudge_persistence");
+
+        // ── Aggression ──────────────────────────────────────────────────────
+        scale(&mut self.military_base, 1.0 + 0.15 * aggression);
+        scale(&mut self.military_threat_scale, 1.0 + 0.15 * aggression);
+        scale(&mut self.military_melee_need, 1.0 + 0.12 * aggression);
+        scale(&mut self.military_ranged_need, 1.0 + 0.10 * aggression);
+        scale(&mut self.threat_penalty, 1.0 - 0.08 * aggression);
+
+        // ── Expansion ───────────────────────────────────────────────────────
+        scale(&mut self.expansion_base, 1.0 + 0.20 * expansion);
+        scale(&mut self.site_food, 1.0 + 0.10 * expansion);
+        scale(&mut self.site_resource, 1.0 + 0.10 * expansion);
+        scale(&mut self.expansion_diminish_rate, 1.0 - 0.15 * expansion);
+
+        // ── Production ──────────────────────────────────────────────────────
+        scale(&mut self.site_prod, 1.0 + 0.15 * production);
+        scale(&mut self.effect_prod, 1.0 + 0.18 * production);
+        scale(&mut self.yield_prod, 1.0 + 0.15 * production);
+
+        // ── Wealth ──────────────────────────────────────────────────────────
+        scale(&mut self.site_gold, 1.0 + 0.15 * wealth);
+        scale(&mut self.effect_gold, 1.0 + 0.18 * wealth);
+        scale(&mut self.yield_gold, 1.0 + 0.15 * wealth);
+
+        // ── Trade willingness ───────────────────────────────────────────────
+        scale(&mut self.effect_gold, 1.0 + 0.06 * trade);
+
+        // ── Grudge persistence ──────────────────────────────────────────────
+        scale(&mut self.threat_penalty, 1.0 - 0.06 * grudge);
+    }
+
+    /// Serialize to a flat Vec for CMA-ES. Order must match `from_vec`.
+    pub fn to_vec(&self) -> Vec<f64> {
+        vec![
+            f64::from(self.site_food),
+            f64::from(self.site_prod),
+            f64::from(self.site_gold),
+            f64::from(self.site_quality),
+            f64::from(self.site_resource),
+            f64::from(self.effect_food),
+            f64::from(self.effect_prod),
+            f64::from(self.effect_gold),
+            f64::from(self.effect_science),
+            f64::from(self.effect_culture),
+            f64::from(self.effect_defense),
+            f64::from(self.food_deficit_bonus),
+            f64::from(self.military_base),
+            f64::from(self.military_threat_scale),
+            f64::from(self.military_melee_need),
+            f64::from(self.military_ranged_need),
+            f64::from(self.military_flying_need),
+            f64::from(self.expansion_base),
+            f64::from(self.expansion_diminish_rate),
+            f64::from(self.expansion_econ_threshold),
+            f64::from(self.yield_food),
+            f64::from(self.yield_prod),
+            f64::from(self.yield_gold),
+            f64::from(self.yield_science),
+            f64::from(self.yield_culture),
+            f64::from(self.pop_value),
+            f64::from(self.city_expansion),
+            f64::from(self.threat_penalty),
+        ]
+    }
+
+    /// Deserialize from a flat Vec. Values are clamped to sane ranges.
+    ///
+    /// Panics if `v.len() < Self::N`.
+    pub fn from_vec(v: &[f64]) -> Self {
+        assert!(v.len() >= Self::N, "weight vector too short");
+        let pos = |x: f64| x.max(0.01) as f32;
+        Self {
+            site_food: pos(v[0]),
+            site_prod: pos(v[1]),
+            site_gold: pos(v[2]),
+            site_quality: pos(v[3]),
+            site_resource: pos(v[4]),
+            effect_food: pos(v[5]),
+            effect_prod: pos(v[6]),
+            effect_gold: pos(v[7]),
+            effect_science: pos(v[8]),
+            effect_culture: pos(v[9]),
+            effect_defense: pos(v[10]),
+            food_deficit_bonus: pos(v[11]),
+            military_base: pos(v[12]),
+            military_threat_scale: pos(v[13]),
+            military_melee_need: pos(v[14]),
+            military_ranged_need: pos(v[15]),
+            military_flying_need: pos(v[16]),
+            expansion_base: pos(v[17]),
+            expansion_diminish_rate: pos(v[18]),
+            expansion_econ_threshold: pos(v[19]),
+            yield_food: pos(v[20]),
+            yield_prod: pos(v[21]),
+            yield_gold: pos(v[22]),
+            yield_science: pos(v[23]),
+            yield_culture: pos(v[24]),
+            pop_value: pos(v[25]),
+            city_expansion: pos(v[26]),
+            threat_penalty: pos(v[27]),
+        }
+    }
+}
+
+/// Read a strategic axis (1..=10 JSON scale) and return its neutral-centered
+/// delta as an `f32`. Missing axes default to 5 (neutral) so a partial JSON
+/// entry degrades gracefully instead of producing an extreme clan.
+pub fn axis_delta(axes: &HashMap<String, i32>, key: &str) -> f32 {
+    let raw = *axes.get(key).unwrap_or(&5);
+    let clamped = raw.clamp(1, 10);
+    (clamped as f32) - 5.0
+}
+
+/// Multiply a weight by `factor`, clamping the result to `[0.25x, 2.5x]` of
+/// the pre-scaled value so extreme axes can't zero out or blow up a knob
+/// past what CMA-ES expects to search over.
+pub fn scale(weight: &mut f32, factor: f32) {
+    let clamped = factor.clamp(0.25, 2.5);
+    *weight *= clamped;
+}