diff --git a/crates/aura-cli/src/main.rs b/crates/aura-cli/src/main.rs
index b6c28ce..f62d5e9 100644
--- a/crates/aura-cli/src/main.rs
+++ b/crates/aura-cli/src/main.rs
@@ -556,7 +556,7 @@ fn run_sample(trace: Option<&str>) -> RunReport {
         vec![
             ("sma_fast".to_string(), Scalar::i64(2)),
             ("sma_slow".to_string(), Scalar::i64(4)),
-            ("exposure_scale".to_string(), Scalar::f64(0.5)),
+            ("bias_scale".to_string(), Scalar::f64(0.5)),
         ],
         window,
         0,
@@ -593,7 +593,7 @@ fn run_sample_real(symbol: &str, from_ms: Option<i64>, to_ms: Option<i64>, trace
         vec![
             ("sma_fast".to_string(), Scalar::i64(2)),
             ("sma_slow".to_string(), Scalar::i64(4)),
-            ("exposure_scale".to_string(), Scalar::f64(0.5)),
+            ("bias_scale".to_string(), Scalar::f64(0.5)),
         ],
         window,
         0,
@@ -949,7 +949,7 @@ fn sample_blueprint_with_sinks(pip_size: f64) -> (
     let (tx_ex, rx_ex) = mpsc::channel();
     let mut g = GraphBuilder::new("sample");
     let sig = g.add(signals("signals"));
-    let exposure = g.add(Bias::builder().named("exposure"));
+    let exposure = g.add(Bias::builder().named("bias"));
     let broker = g.add(SimBroker::builder(pip_size));
     let eq = g.add(Recorder::builder(vec![ScalarKind::F64], Firing::Any, tx_eq));
     let ex = g.add(Recorder::builder(vec![ScalarKind::F64], Firing::Any, tx_ex));
@@ -994,7 +994,7 @@ fn sweep_family(trace: Option<&str>, data: &DataSource) -> SweepFamily {
         .axis("signals.momentum.signal.length", [msig])
         .axis("signals.blend.weights[0]", [1.0])
         .axis("signals.blend.weights[1]", [1.0])
-        .axis("exposure.scale", [0.5]);
+        .axis("bias.scale", [0.5]);
     let varying: HashSet<String> = binder.varying_axes().into_iter().collect();
     binder
         .sweep(|point| {
@@ -1023,7 +1023,7 @@ fn sweep_family(trace: Option<&str>, data: &DataSource) -> SweepFamily {
 /// The signal is how far price sits above/below its own EMA (`price - ema`), bounded
 /// into a directional (unsized) bias by `Bias`, then passed through the long-only
 /// `LongOnly` gate. Three swept
-/// knobs of three kinds — `ema.length` (i64), `exposure.scale` (f64),
+/// knobs of three kinds — `ema.length` (i64), `bias.scale` (f64),
 /// `longonly.enabled` (bool) — with nothing in common with the SMA-cross demo: the
 /// generic-sweep proof. The exposure sink taps the FINAL (gated) exposure so the
 /// bool's effect is visible in the trace.
@@ -1037,11 +1037,11 @@ fn momentum_blueprint_with_sinks(pip_size: f64) -> (
     let (tx_ex, rx_ex) = mpsc::channel();
     let mut g = GraphBuilder::new("momentum");
     // Name the param-bearing nodes explicitly so the swept paths are guaranteed
-    // ema.length / exposure.scale / longonly.enabled regardless of default-name
+    // ema.length / bias.scale / longonly.enabled regardless of default-name
     // derivation (the member-key examples + the param-space test depend on these).
     let ema = g.add(Ema::builder().named("ema")); // ema.length
     let dist = g.add(Sub::builder()); // momentum = price - ema
-    let expo = g.add(Bias::builder().named("exposure")); // exposure.scale
+    let expo = g.add(Bias::builder().named("bias")); // bias.scale
     let gate = g.add(LongOnly::builder().named("longonly")); // longonly.enabled (the bool param)
     let broker = g.add(SimBroker::builder(pip_size));
     let eq = g.add(Recorder::builder(vec![ScalarKind::F64], Firing::Any, tx_eq));
@@ -1059,7 +1059,7 @@ fn momentum_blueprint_with_sinks(pip_size: f64) -> (
 }
 
 /// Run the momentum strategy over its built-in grid — `ema.length ∈ {5,10}` ×
-/// `exposure.scale ∈ {0.5,1.0}` × `longonly.enabled ∈ {true,false}` = 8 points,
+/// `bias.scale ∈ {0.5,1.0}` × `longonly.enabled ∈ {true,false}` = 8 points,
 /// all three axes varying. Mirrors `sweep_family`: capture the binder's varying
 /// axes, key each member via the generic portable `member_key`. With `--trace`,
 /// persist each member under `runs/traces/<name>/<member_key>/`.
@@ -1070,7 +1070,7 @@ fn momentum_sweep_family(trace: Option<&str>, data: &DataSource) -> SweepFamily
     let space = bp.param_space();
     let binder = bp
         .axis("ema.length", [5, 10])
-        .axis("exposure.scale", [0.5, 1.0])
+        .axis("bias.scale", [0.5, 1.0])
         .axis("longonly.enabled", [true, false]);
     let varying: HashSet<String> = binder.varying_axes().into_iter().collect();
     binder
@@ -1315,7 +1315,7 @@ fn sweep_over(from: Timestamp, to: Timestamp, data: &DataSource) -> SweepFamily
         .axis("signals.momentum.signal.length", [msig])
         .axis("signals.blend.weights[0]", [1.0])
         .axis("signals.blend.weights[1]", [1.0])
-        .axis("exposure.scale", [0.5])
+        .axis("bias.scale", [0.5])
         .sweep(|point| {
             let (bp, rx_eq, rx_ex) = sample_blueprint_with_sinks(pip);
             let mut h = bp
@@ -1438,7 +1438,7 @@ fn mc_family(trace: Option<&str>) -> McFamily {
             vec![
                 ("sma_fast".to_string(), Scalar::i64(2)),
                 ("sma_slow".to_string(), Scalar::i64(4)),
-                ("exposure_scale".to_string(), Scalar::f64(0.5)),
+                ("bias_scale".to_string(), Scalar::f64(0.5)),
             ],
             window,
             seed,
@@ -1600,7 +1600,7 @@ fn macd_strategy_blueprint(
 ) -> Composite {
     let mut g = GraphBuilder::new("macd_strategy");
     let macd_node = g.add(macd("macd"));
-    let exposure = g.add(Bias::builder().named("exposure"));
+    let exposure = g.add(Bias::builder().named("bias"));
     let broker = g.add(SimBroker::builder(SYNTHETIC_PIP_SIZE));
     let eq = g.add(Recorder::builder(vec![ScalarKind::F64], Firing::Any, tx_eq));
     let ex = g.add(Recorder::builder(vec![ScalarKind::F64], Firing::Any, tx_ex));
@@ -1674,7 +1674,7 @@ fn run_macd(trace: Option<&str>) -> RunReport {
             ("ema_fast".to_string(), Scalar::i64(2)),
             ("ema_slow".to_string(), Scalar::i64(4)),
             ("ema_signal".to_string(), Scalar::i64(3)),
-            ("exposure_scale".to_string(), Scalar::f64(0.5)),
+            ("bias_scale".to_string(), Scalar::f64(0.5)),
         ],
         window,
         0,
@@ -1737,7 +1737,7 @@ fn stage1_r_blueprint(
     let fast = g.add(Sma::builder().named("fast").bind("length", Scalar::i64(2)));
     let slow = g.add(Sma::builder().named("slow").bind("length", Scalar::i64(4)));
     let spread = g.add(Sub::builder());
-    let exposure = g.add(Bias::builder().named("exposure").bind("scale", Scalar::f64(0.5)));
+    let exposure = g.add(Bias::builder().named("bias").bind("scale", Scalar::f64(0.5)));
     // pip branch (verbatim from sample_blueprint_with_sinks).
     let broker = g.add(SimBroker::builder(SYNTHETIC_PIP_SIZE));
     let eq = g.add(Recorder::builder(vec![ScalarKind::F64], Firing::Any, tx_eq));
@@ -1824,7 +1824,7 @@ fn run_stage1_r(data: RunData, trace: Option<&str>) -> RunReport {
         vec![
             ("sma_fast".to_string(), Scalar::i64(2)),
             ("sma_slow".to_string(), Scalar::i64(4)),
-            ("exposure_scale".to_string(), Scalar::f64(0.5)),
+            ("bias_scale".to_string(), Scalar::f64(0.5)),
             ("stop_length".to_string(), Scalar::i64(STAGE1_R_STOP_LENGTH)), // vol_stop EWMA length
             ("stop_k".to_string(), Scalar::f64(STAGE1_R_STOP_K)),           // vol_stop multiplier (1R = k·σ)
         ],
@@ -2394,7 +2394,7 @@ mod tests {
                 vec![
                     ("sma_fast".to_string(), Scalar::i64(2)),
                     ("sma_slow".to_string(), Scalar::i64(4)),
-                    ("exposure_scale".to_string(), Scalar::f64(0.5)),
+                    ("bias_scale".to_string(), Scalar::f64(0.5)),
                 ],
                 window,
                 seed,
@@ -2441,7 +2441,7 @@ mod tests {
             .with("signals.momentum.signal.length", 3)
             .with("signals.blend.weights[0]", 1.0)
             .with("signals.blend.weights[1]", 1.0)
-            .with("exposure.scale", 0.5)
+            .with("bias.scale", 0.5)
             .bootstrap()
             .expect("sample blueprint compiles under a valid point");
         h.run(vec![Box::new(VecSource::new(showcase_prices()))]);
@@ -2460,10 +2460,10 @@ mod tests {
         for line in &lines {
             assert!(line.starts_with(r#"{"manifest":{"commit":""#), "not a RunReport: {line}");
         }
-        assert!(lines[0].contains(r#""params":[["signals.trend.fast.length",{"I64":2}],["signals.trend.slow.length",{"I64":4}],["signals.momentum.fast.length",{"I64":2}],["signals.momentum.slow.length",{"I64":4}],["signals.momentum.signal.length",{"I64":3}],["signals.blend.weights[0]",{"F64":1.0}],["signals.blend.weights[1]",{"F64":1.0}],["exposure.scale",{"F64":0.5}]]"#), "line0: {}", lines[0]);
-        assert!(lines[1].contains(r#""params":[["signals.trend.fast.length",{"I64":2}],["signals.trend.slow.length",{"I64":5}],["signals.momentum.fast.length",{"I64":2}],["signals.momentum.slow.length",{"I64":4}],["signals.momentum.signal.length",{"I64":3}],["signals.blend.weights[0]",{"F64":1.0}],["signals.blend.weights[1]",{"F64":1.0}],["exposure.scale",{"F64":0.5}]]"#), "line1: {}", lines[1]);
-        assert!(lines[2].contains(r#""params":[["signals.trend.fast.length",{"I64":3}],["signals.trend.slow.length",{"I64":4}],["signals.momentum.fast.length",{"I64":2}],["signals.momentum.slow.length",{"I64":4}],["signals.momentum.signal.length",{"I64":3}],["signals.blend.weights[0]",{"F64":1.0}],["signals.blend.weights[1]",{"F64":1.0}],["exposure.scale",{"F64":0.5}]]"#), "line2: {}", lines[2]);
-        assert!(lines[3].contains(r#""params":[["signals.trend.fast.length",{"I64":3}],["signals.trend.slow.length",{"I64":5}],["signals.momentum.fast.length",{"I64":2}],["signals.momentum.slow.length",{"I64":4}],["signals.momentum.signal.length",{"I64":3}],["signals.blend.weights[0]",{"F64":1.0}],["signals.blend.weights[1]",{"F64":1.0}],["exposure.scale",{"F64":0.5}]]"#), "line3: {}", lines[3]);
+        assert!(lines[0].contains(r#""params":[["signals.trend.fast.length",{"I64":2}],["signals.trend.slow.length",{"I64":4}],["signals.momentum.fast.length",{"I64":2}],["signals.momentum.slow.length",{"I64":4}],["signals.momentum.signal.length",{"I64":3}],["signals.blend.weights[0]",{"F64":1.0}],["signals.blend.weights[1]",{"F64":1.0}],["bias.scale",{"F64":0.5}]]"#), "line0: {}", lines[0]);
+        assert!(lines[1].contains(r#""params":[["signals.trend.fast.length",{"I64":2}],["signals.trend.slow.length",{"I64":5}],["signals.momentum.fast.length",{"I64":2}],["signals.momentum.slow.length",{"I64":4}],["signals.momentum.signal.length",{"I64":3}],["signals.blend.weights[0]",{"F64":1.0}],["signals.blend.weights[1]",{"F64":1.0}],["bias.scale",{"F64":0.5}]]"#), "line1: {}", lines[1]);
+        assert!(lines[2].contains(r#""params":[["signals.trend.fast.length",{"I64":3}],["signals.trend.slow.length",{"I64":4}],["signals.momentum.fast.length",{"I64":2}],["signals.momentum.slow.length",{"I64":4}],["signals.momentum.signal.length",{"I64":3}],["signals.blend.weights[0]",{"F64":1.0}],["signals.blend.weights[1]",{"F64":1.0}],["bias.scale",{"F64":0.5}]]"#), "line2: {}", lines[2]);
+        assert!(lines[3].contains(r#""params":[["signals.trend.fast.length",{"I64":3}],["signals.trend.slow.length",{"I64":5}],["signals.momentum.fast.length",{"I64":2}],["signals.momentum.slow.length",{"I64":4}],["signals.momentum.signal.length",{"I64":3}],["signals.blend.weights[0]",{"F64":1.0}],["signals.blend.weights[1]",{"F64":1.0}],["bias.scale",{"F64":0.5}]]"#), "line3: {}", lines[3]);
         for line in &lines {
             assert!(line.contains(r#""total_pips":"#), "missing total_pips: {line}");
             assert!(line.contains(r#""max_drawdown":"#), "missing max_drawdown: {line}");
@@ -2565,7 +2565,7 @@ mod tests {
     /// EMA `length` slots by node name to `macd.fast.length` / `macd.slow.length` /
     /// `macd.signal.length` — the named composite boundary visible end-to-end through
     /// `param_space()`, with the slot count and order unchanged (C23 — node names are
-    /// non-load-bearing: every interior slot stays sweepable, the `exposure.scale`
+    /// non-load-bearing: every interior slot stays sweepable, the `bias.scale`
     /// knob is unaffected).
     #[test]
     fn macd_param_space_surfaces_the_three_named_legs() {
@@ -2579,7 +2579,7 @@ mod tests {
                 "macd.fast.length".to_string(),
                 "macd.slow.length".to_string(),
                 "macd.signal.length".to_string(),
-                "exposure.scale".to_string(),
+                "bias.scale".to_string(),
             ],
             "MACD param surface must expose the three named EMA lengths + scale",
         );
@@ -2757,13 +2757,13 @@ mod tests {
     fn member_key_renders_varying_axes_portably() {
         let named = vec![
             pair("ema.length", Scalar::i64(5)),
-            pair("exposure.scale", Scalar::f64(0.5)),
+            pair("bias.scale", Scalar::f64(0.5)),
             pair("longonly.enabled", Scalar::bool(true)),
         ];
         let varying: std::collections::HashSet<String> =
             named.iter().map(|(n, _)| n.clone()).collect();
         let key = member_key(&named, &varying);
-        assert_eq!(key, "ema.length-5_exposure.scale-0.5_longonly.enabled-true");
+        assert_eq!(key, "ema.length-5_bias.scale-0.5_longonly.enabled-true");
         assert!(key.chars().all(|c| c.is_ascii_alphanumeric() || matches!(c, '.' | '_' | '-')));
     }
 
@@ -2771,7 +2771,7 @@ mod tests {
     fn member_key_omits_pinned_axes() {
         let named = vec![
             pair("ema.length", Scalar::i64(5)),
-            pair("exposure.scale", Scalar::f64(0.5)),
+            pair("bias.scale", Scalar::f64(0.5)),
             pair("longonly.enabled", Scalar::bool(false)),
         ];
         let mut varying = std::collections::HashSet::new();
@@ -2781,10 +2781,10 @@ mod tests {
 
     #[test]
     fn member_key_handles_negative_float_and_sanitises_names() {
-        let named = vec![pair("exposure.scale", Scalar::f64(-0.5))];
+        let named = vec![pair("bias.scale", Scalar::f64(-0.5))];
         let varying: std::collections::HashSet<String> =
-            ["exposure.scale".to_string()].into_iter().collect();
-        assert_eq!(member_key(&named, &varying), "exposure.scale--0.5");
+            ["bias.scale".to_string()].into_iter().collect();
+        assert_eq!(member_key(&named, &varying), "bias.scale--0.5");
 
         let named2 = vec![pair("weird key!", Scalar::f64(1.0))];
         let varying2: std::collections::HashSet<String> =
@@ -2794,7 +2794,7 @@ mod tests {
 
     #[test]
     fn member_key_is_m_when_no_axis_varies() {
-        let named = vec![pair("exposure.scale", Scalar::f64(0.5))];
+        let named = vec![pair("bias.scale", Scalar::f64(0.5))];
         let varying = std::collections::HashSet::new();
         assert_eq!(member_key(&named, &varying), "m");
     }
@@ -2816,15 +2816,15 @@ mod tests {
 
     #[test]
     fn member_key_collision_free_over_a_non_trend_axis_set() {
-        // #105 regression: vary exposure.scale + a bool (NOT the old hardcoded
+        // #105 regression: vary bias.scale + a bool (NOT the old hardcoded
         // trend.fast/slow). Distinct points -> distinct keys; the old f…s… key
         // would have collapsed them all to one dir.
         let varying: std::collections::HashSet<String> =
-            ["exposure.scale".to_string(), "longonly.enabled".to_string()].into_iter().collect();
+            ["bias.scale".to_string(), "longonly.enabled".to_string()].into_iter().collect();
         let p = |s: f64, b: bool| {
             vec![
                 pair("ema.length", Scalar::i64(5)), // pinned -> omitted from key
-                pair("exposure.scale", Scalar::f64(s)),
+                pair("bias.scale", Scalar::f64(s)),
                 pair("longonly.enabled", Scalar::bool(b)),
             ]
         };
@@ -2846,7 +2846,7 @@ mod tests {
             names,
             vec![
                 "ema.length".to_string(),
-                "exposure.scale".to_string(),
+                "bias.scale".to_string(),
                 "longonly.enabled".to_string(),
             ],
         );
diff --git a/crates/aura-cli/tests/cli_run.rs b/crates/aura-cli/tests/cli_run.rs
index c155268..4b0fdb7 100644
--- a/crates/aura-cli/tests/cli_run.rs
+++ b/crates/aura-cli/tests/cli_run.rs
@@ -635,7 +635,7 @@ fn sweep_prints_four_family_json_lines_and_exits_zero() {
     // `broker` (the commit value is the volatile git HEAD, pinned by params below).
     assert!(first.starts_with("{\"family_id\":\"sweep-0\",\"report\":{\"manifest\":{"), "got: {stdout}");
     assert!(
-        first.contains("\"params\":[[\"signals.trend.fast.length\",{\"I64\":2}],[\"signals.trend.slow.length\",{\"I64\":4}],[\"signals.momentum.fast.length\",{\"I64\":2}],[\"signals.momentum.slow.length\",{\"I64\":4}],[\"signals.momentum.signal.length\",{\"I64\":3}],[\"signals.blend.weights[0]\",{\"F64\":1.0}],[\"signals.blend.weights[1]\",{\"F64\":1.0}],[\"exposure.scale\",{\"F64\":0.5}]]"),
+        first.contains("\"params\":[[\"signals.trend.fast.length\",{\"I64\":2}],[\"signals.trend.slow.length\",{\"I64\":4}],[\"signals.momentum.fast.length\",{\"I64\":2}],[\"signals.momentum.slow.length\",{\"I64\":4}],[\"signals.momentum.signal.length\",{\"I64\":3}],[\"signals.blend.weights[0]\",{\"F64\":1.0}],[\"signals.blend.weights[1]\",{\"F64\":1.0}],[\"bias.scale\",{\"F64\":0.5}]]"),
         "got: {stdout}"
     );
     let _ = std::fs::remove_dir_all(&cwd);
@@ -1035,7 +1035,7 @@ fn sweep_strategy_momentum_prints_eight_typed_bool_member_lines() {
 /// Property (#105, the bool actually gates — observable on disk): the
 /// `longonly.enabled` param is genuinely WIRED into the momentum harness, not a
 /// no-op knob. For one grid point's two bool members (same `ema.length` +
-/// `exposure.scale`, differing only in the bool), the `enabled=true` member
+/// `bias.scale`, differing only in the bool), the `enabled=true` member
 /// records a long-only exposure stream — every recorded value `>= 0` — while the
 /// otherwise-identical `enabled=false` member records at least one NEGATIVE
 /// exposure over the same deterministic showcase stream. This pins the gate's
@@ -1063,8 +1063,8 @@ fn momentum_longonly_true_clamps_exposure_nonnegative_false_keeps_negatives() {
 
     // One grid point, its two bool members (identical but for the bool).
     let base = cwd.join("runs/traces/gate");
-    let enabled = base.join("ema.length-5_exposure.scale-1_longonly.enabled-true");
-    let disabled = base.join("ema.length-5_exposure.scale-1_longonly.enabled-false");
+    let enabled = base.join("ema.length-5_bias.scale-1_longonly.enabled-true");
+    let disabled = base.join("ema.length-5_bias.scale-1_longonly.enabled-false");
 
     let exposures = |dir: &std::path::Path| -> Vec<f64> {
         let body = std::fs::read_to_string(dir.join("exposure.json")).expect("read exposure.json");
diff --git a/crates/aura-engine/src/blueprint.rs b/crates/aura-engine/src/blueprint.rs
index 790c028..c9eadcb 100644
--- a/crates/aura-engine/src/blueprint.rs
+++ b/crates/aura-engine/src/blueprint.rs
@@ -304,7 +304,7 @@ impl Composite {
     /// fluent alternative to a positional `bootstrap_with_params` vector). The
     /// bound name is the exact `param_space()` name — `<node>.<param>` at every
     /// level, e.g. `sma_cross.fast.length` for a composite-interior knob and
-    /// `exposure.scale` for a root-level knob.
+    /// `bias.scale` for a root-level knob.
     pub fn with(self, name: &str, v: impl Into<Scalar>) -> Binder {
         Binder { bp: self, bound: vec![(name.to_string(), v.into())] }
     }
@@ -962,7 +962,7 @@ mod tests {
             .0
             .range("sma_cross.fast.length", fast)
             .range("sma_cross.slow.length", slow)
-            .range("exposure.scale", scale)
+            .range("bias.scale", scale)
             .sweep(count, seed, run_point)
             .expect("named ranges resolve against param_space()");
 
@@ -972,7 +972,7 @@ mod tests {
             .0
             .range("sma_cross.slow.length", slow)
             .range("sma_cross.fast.length", fast)
-            .range("exposure.scale", scale)
+            .range("bias.scale", scale)
             .sweep(count, seed, run_point)
             .expect("named ranges resolve regardless of call order");
 
@@ -1078,7 +1078,7 @@ mod tests {
         let result = bp
             .axis("sma_cross.fast.length", [2.0, 3.0]) // F64 values for the I64 slot
             .axis("sma_cross.slow.length", [4])
-            .axis("exposure.scale", [0.5])
+            .axis("bias.scale", [0.5])
             .sweep(|_: &[Cell]| -> RunReport { panic!("axis pre-validation must reject before running") });
         assert_eq!(
             result,
@@ -1100,7 +1100,7 @@ mod tests {
             &[
                 ("sma_cross.fast.length".to_string(), vec![Scalar::i64(2), Scalar::i64(3)]),
                 ("sma_cross.slow.length".to_string(), vec![Scalar::i64(4), Scalar::i64(5)]),
-                ("exposure.scale".to_string(), vec![Scalar::f64(0.5)]),
+                ("bias.scale".to_string(), vec![Scalar::f64(0.5)]),
             ],
         )
         .expect("named axes resolve");
@@ -1209,7 +1209,7 @@ mod tests {
         let mut named = bp
             .with("sma_cross.fast.length", 2)
             .with("sma_cross.slow.length", 4)
-            .with("exposure.scale", 0.5)
+            .with("bias.scale", 0.5)
             .bootstrap()
             .expect("named binding resolves and bootstraps");
         named.run(vec![Box::new(VecSource::new(synthetic_prices()))]);
@@ -2104,7 +2104,7 @@ mod tests {
         // scale (F64); Sub/SimBroker/Recorder declare none
         assert_eq!(
             space.iter().map(|p| p.name.as_str()).collect::<Vec<_>>(),
-            ["sma_cross.fast.length", "sma_cross.slow.length", "exposure.scale"],
+            ["sma_cross.fast.length", "sma_cross.slow.length", "bias.scale"],
         );
         assert_eq!(
             space.iter().map(|p| p.kind).collect::<Vec<_>>(),
@@ -2563,7 +2563,7 @@ mod tests {
             "root",
             vec![
                 BlueprintNode::Composite(cross),
-                Bias::builder().named("exposure").into(),
+                Bias::builder().named("bias").into(),
                 Recorder::builder(vec![ScalarKind::F64], Firing::Any, tx_ex).into(),
             ],
             vec![
@@ -2583,7 +2583,7 @@ mod tests {
         let mut h = bp
             .with("sma_cross.fast.length", 2)
             .with("sma_cross.slow.length", 4)
-            .with("exposure.scale", 0.5)
+            .with("bias.scale", 0.5)
             .bootstrap()
             .expect("named (injective) cross resolves by name and bootstraps");
         h.run(vec![Box::new(VecSource::new(prices))]);
diff --git a/crates/aura-engine/src/builder.rs b/crates/aura-engine/src/builder.rs
index 2427a1d..0e1ea6d 100644
--- a/crates/aura-engine/src/builder.rs
+++ b/crates/aura-engine/src/builder.rs
@@ -236,7 +236,7 @@ mod tests {
         use aura_core::Scalar;
 
         // Shared param vector for the harness param-space (sma_cross.fast.length,
-        // sma_cross.slow.length, exposure.scale) — applied to both sides, so it
+        // sma_cross.slow.length, bias.scale) — applied to both sides, so it
         // cancels in the comparison. Params size buffers, not topology (C11), so
         // edges/sources are param-independent; a fixed vector just satisfies the
         // arity gate compile() (no-param) trips on this value-empty harness.
diff --git a/crates/aura-engine/src/report.rs b/crates/aura-engine/src/report.rs
index dc13443..302256e 100644
--- a/crates/aura-engine/src/report.rs
+++ b/crates/aura-engine/src/report.rs
@@ -637,7 +637,7 @@ mod tests {
                 params: vec![
                     ("sma_fast".to_string(), Scalar::i64(2)),
                     ("sma_slow".to_string(), Scalar::i64(4)),
-                    ("exposure_scale".to_string(), Scalar::f64(0.5)),
+                    ("bias_scale".to_string(), Scalar::f64(0.5)),
                 ],
                 window: (Timestamp(1), Timestamp(5)),
                 seed: 0,
@@ -879,7 +879,7 @@ mod tests {
                 params: vec![
                     ("sma_fast".to_string(), Scalar::i64(2)),
                     ("sma_slow".to_string(), Scalar::i64(4)),
-                    ("exposure_scale".to_string(), Scalar::f64(1.0)),
+                    ("bias_scale".to_string(), Scalar::f64(1.0)),
                 ],
                 window: (Timestamp(1), Timestamp(6)),
                 seed: 0,
@@ -894,7 +894,7 @@ mod tests {
         };
         assert_eq!(
             report.to_json(),
-            r#"{"manifest":{"commit":"abc123","params":[["sma_fast",{"I64":2}],["sma_slow",{"I64":4}],["exposure_scale",{"F64":1.0}]],"window":[1,6],"seed":0,"broker":"sim-optimal(pip_size=1.0)"},"metrics":{"total_pips":12.0,"max_drawdown":1.0,"bias_sign_flips":1}}"#,
+            r#"{"manifest":{"commit":"abc123","params":[["sma_fast",{"I64":2}],["sma_slow",{"I64":4}],["bias_scale",{"F64":1.0}]],"window":[1,6],"seed":0,"broker":"sim-optimal(pip_size=1.0)"},"metrics":{"total_pips":12.0,"max_drawdown":1.0,"bias_sign_flips":1}}"#,
         );
     }
 
@@ -907,7 +907,7 @@ mod tests {
                 params: vec![
                     ("sma_fast".to_string(), Scalar::i64(2)),
                     ("sma_slow".to_string(), Scalar::i64(4)),
-                    ("exposure_scale".to_string(), Scalar::f64(1.0)),
+                    ("bias_scale".to_string(), Scalar::f64(1.0)),
                 ],
                 window: (Timestamp(1), Timestamp(6)),
                 seed: 0,
@@ -927,7 +927,7 @@ mod tests {
                 params: vec![
                     ("sma_fast".to_string(), Scalar::i64(2)),
                     ("sma_slow".to_string(), Scalar::i64(4)),
-                    ("exposure_scale".to_string(), Scalar::f64(1.0)),
+                    ("bias_scale".to_string(), Scalar::f64(1.0)),
                 ],
                 window: (Timestamp(1), Timestamp(6)),
                 seed: 0,
diff --git a/crates/aura-engine/src/test_fixtures.rs b/crates/aura-engine/src/test_fixtures.rs
index 8150330..d4929a5 100644
--- a/crates/aura-engine/src/test_fixtures.rs
+++ b/crates/aura-engine/src/test_fixtures.rs
@@ -62,7 +62,7 @@ pub(crate) fn composite_sma_cross_harness() -> (
         "root",
         vec![
             BlueprintNode::Composite(sma_cross()),
-            Bias::builder().named("exposure").into(),
+            Bias::builder().named("bias").into(),
             SimBroker::builder(0.0001).into(),
             Recorder::builder(vec![ScalarKind::F64], Firing::Any, tx_eq).into(),
             Recorder::builder(vec![ScalarKind::F64], Firing::Any, tx_ex).into(),
diff --git a/crates/aura-engine/src/walkforward.rs b/crates/aura-engine/src/walkforward.rs
index 43e4f10..3628dc4 100644
--- a/crates/aura-engine/src/walkforward.rs
+++ b/crates/aura-engine/src/walkforward.rs
@@ -467,7 +467,7 @@ mod tests {
         let result = WalkForwardResult {
             space: vec![
                 ParamSpec { name: "sma.fast".to_string(), kind: ScalarKind::I64 },
-                ParamSpec { name: "exposure.scale".to_string(), kind: ScalarKind::F64 },
+                ParamSpec { name: "bias.scale".to_string(), kind: ScalarKind::F64 },
             ],
             windows: vec![mk(8, 0.25), mk(13, 0.75)],
             stitched_oos_equity: vec![],
@@ -476,14 +476,14 @@ mod tests {
             result.named_params(0),
             vec![
                 ("sma.fast".to_string(), Scalar::i64(8)),
-                ("exposure.scale".to_string(), Scalar::f64(0.25)),
+                ("bias.scale".to_string(), Scalar::f64(0.25)),
             ],
         );
         assert_eq!(
             result.named_params(1),
             vec![
                 ("sma.fast".to_string(), Scalar::i64(13)),
-                ("exposure.scale".to_string(), Scalar::f64(0.75)),
+                ("bias.scale".to_string(), Scalar::f64(0.75)),
             ],
         );
     }
diff --git a/crates/aura-ingest/tests/real_bars.rs b/crates/aura-ingest/tests/real_bars.rs
index 7b88dff..af651e0 100644
--- a/crates/aura-ingest/tests/real_bars.rs
+++ b/crates/aura-ingest/tests/real_bars.rs
@@ -84,7 +84,7 @@ fn run_sample_over(prices: Vec<(Timestamp, Scalar)>) -> RunReport {
             params: vec![
                 ("sma_fast".to_string(), Scalar::i64(2)),
                 ("sma_slow".to_string(), Scalar::i64(4)),
-                ("exposure_scale".to_string(), Scalar::f64(0.5)),
+                ("bias_scale".to_string(), Scalar::f64(0.5)),
             ],
             window,
             seed: 0,
diff --git a/crates/aura-ingest/tests/streaming_seam.rs b/crates/aura-ingest/tests/streaming_seam.rs
index ae8b2fc..f81cc38 100644
--- a/crates/aura-ingest/tests/streaming_seam.rs
+++ b/crates/aura-ingest/tests/streaming_seam.rs
@@ -84,7 +84,7 @@ fn run_sample(window: (Timestamp, Timestamp), source: Box<dyn Source>) -> RunRep
             params: vec![
                 ("sma_fast".to_string(), Scalar::i64(2)),
                 ("sma_slow".to_string(), Scalar::i64(4)),
-                ("exposure_scale".to_string(), Scalar::f64(0.5)),
+                ("bias_scale".to_string(), Scalar::f64(0.5)),
             ],
             window,
             seed: 0,
diff --git a/docs/design/INDEX.md b/docs/design/INDEX.md
index 8e9ef6d..3eba19a 100644
--- a/docs/design/INDEX.md
+++ b/docs/design/INDEX.md
@@ -606,9 +606,12 @@ runnable GER40 examples (already at the correct `1.0`) are routed through the sa
 lookup separately (#98).
 **Realization (cycle 0065 — Stage-1 R signal quality, #119/#126/#127/#128/#129).**
 The Stage-1 chain above is now built. `Exposure → Bias` renames the unsized strategy
-output (the node + its output field); the persisted `exposure_sign_flips` metric key,
-the `SimBroker` `exposure` input slot, and the `exposure_scale` manifest param keep
-the old name as **serde-stable residue** — a deferred rename tail. A **stop-rule**
+output (the node + its output field); the persisted `exposure_sign_flips` metric key
+(kept as a serde alias) and the `SimBroker` `exposure` input slot + the on-disk
+`exposure` **tap** label (a deliberate permanent keep, #117) retain the old name. The
+strategy-output **param namespace** — the `Bias` instance, its `bias.scale` knob, and
+the `bias_scale` manifest param — was the deferred rename tail, **completed in #134**
+(the knob path is a runtime address, so no on-disk back-compat break). A **stop-rule**
 defines 1R: `FixedStop` (a triggered-constant primitive) and a `vol_stop(length, k)`
 **composition** `k·√EMA(Δ²)` (the originally-fused node was corrected to a composition
 of new `Mul`/`Sqrt` primitives — a node is a primitive only if not DAG-expressible