feat(cli): sweep axes override bound params on the blueprint verb paths

Task 3-4 of the bound-override cycle. The family boundary derives the
override set from the invocation's axes (override_paths: an axis in the
open space passes through, one naming a bound param re-opens it in
strategy coordinates, one matching neither is refused with a message
pointing at --list-axes) and threads it through the axis probe and every
per-member reload (blueprint_axis_probe_reopened / reopen_all), so probe
and members stay slot-identical. The 'fully bound; nothing to sweep'
refusal retires; identity stays the authored document (the topology_hash
probe reload is never re-opened).

--list-axes now prints the bound surface after the open knobs — one
'<bp>.<node>.<param>:<KIND> default=<value>' line per bound param,
unconditionally (a bound param is an equally re-openable axis regardless
of how many knobs are open beside it).

Walk-forward (blueprint_sweep_over, blueprint_walkforward_family,
run_oos_blueprint) and reproduce (reproduce_family_in plus the
campaign-side trace re-run) derive the same set silently from recorded
manifest param names (bound_overrides_of), so a family that swept an
overridden bound param re-derives bit-identically.

refs #246

crates/aura-cli/src/campaign_run.rs

@@ -839,11 +839,25 @@ pub(crate) fn persist_campaign_traces(
                     cell_rec.strategy
                 )
             })?;
+        // The #246 override set (silent variant, `reproduce_family_in`'s
+        // recipe): re-derived from the cell's own recorded manifest param
+        // names, against a raw probe space + raw strategy load — the members
+        // of one cell share the same knob NAMES (only values differ), so this
+        // is safe to compute once, cell-invariant, from the first member.
+        let raw_space = crate::blueprint_axis_probe(blueprint_json, env).param_space();
+        let raw_signal = blueprint_from_json(blueprint_json, &|t| env.resolve(t))
+            .expect("stored blueprint passed the referential gate; reload is infallible");
+        let recorded: Vec<String> = members
+            .first()
+            .map(|(_, r)| r.manifest.params.iter().map(|(n, _)| n.clone()).collect())
+            .unwrap_or_default();
+        let overrides = crate::bound_overrides_of(&recorded, &raw_space, &raw_signal);
         // Cell-invariant across every member of this cell (the wrapped param
         // space depends only on the cell's blueprint; the resolved geometry
         // only on the cell's instrument) — computed once here rather than
         // redundantly inside the member loop below.
-        let space = crate::blueprint_axis_probe(blueprint_json, env).param_space();
+        let space =
+            crate::blueprint_axis_probe_reopened(blueprint_json, env, &overrides).param_space();
         // Same resolved pip the member ran at (`CliMemberRunner::run_member`'s
         // `geo.pip_size`), else the C1 drift-alarm equality below would trip
         // spuriously on a re-run computed at a different (default) pip.
@@ -872,8 +886,11 @@ pub(crate) fn persist_campaign_traces(
                     cell_rec.instrument, from.0, to.0
                 )
             };
-            let signal = blueprint_from_json(blueprint_json, &|t| env.resolve(t))
-                .expect("stored blueprint passed the referential gate; reload is infallible");
+            let signal = crate::reopen_all(
+                blueprint_from_json(blueprint_json, &|t| env.resolve(t))
+                    .expect("stored blueprint passed the referential gate; reload is infallible"),
+                &overrides,
+            );
             // Campaign data.bindings overrides win over name defaults — the
             // SAME resolution the member ran under, so the C1 drift alarm
             // compares like with like.

crates/aura-cli/src/main.rs

@@ -1222,14 +1222,32 @@ fn reproduce_family_in(
                 eprintln!("aura: blueprint {hash} missing from store");
                 std::process::exit(1);
             });
+        // The #246 override set (silent variant): re-derived from the RECORDED
+        // manifest param names, against a raw probe space + raw strategy load — a
+        // name matching neither space is simply not an override (falls through to
+        // `point_from_params`'s existing missing-knob refusal below), unlike the
+        // sweep boundary's `override_paths`, which errors on it.
+        let recorded: Vec<String> =
+            stored.manifest.params.iter().map(|(n, _)| n.clone()).collect();
+        let raw_space = blueprint_axis_probe(&doc, env).param_space();
+        let raw_signal = blueprint_from_json(&doc, &|t| env.resolve(t)).unwrap_or_else(|e| {
+            eprintln!("aura: stored blueprint {hash} does not parse: {e:?}");
+            std::process::exit(1);
+        });
+        let overrides = bound_overrides_of(&recorded, &raw_space, &raw_signal);
         // Reload the stored blueprint per use: a Composite is !Clone, and both the
         // param-space probe (below) and the re-run each consume one. The doc was
-        // canonical-serialized at store time, so every reload is infallible.
+        // canonical-serialized at store time, so every reload is infallible. Every
+        // reload re-opens the same override set derived above, so the recorded
+        // param names resolve against the space they were minted under (#246).
         let reload = || {
-            blueprint_from_json(&doc, &|t| env.resolve(t)).unwrap_or_else(|e| {
-                eprintln!("aura: stored blueprint {hash} does not parse: {e:?}");
-                std::process::exit(1);
-            })
+            reopen_all(
+                blueprint_from_json(&doc, &|t| env.resolve(t)).unwrap_or_else(|e| {
+                    eprintln!("aura: stored blueprint {hash} does not parse: {e:?}");
+                    std::process::exit(1);
+                }),
+                &overrides,
+            )
         };
         // The param_space of the WRAPPED signal — its knobs carry the `r_sma`
         // wrapper's `sma_signal.` node-path prefix, exactly the names the manifest
@@ -1792,8 +1810,17 @@ fn run_blueprint_member(
 /// boundary before this runs, so a malformed doc has already exited 2 and
 /// never reaches the `.expect`.
 fn blueprint_axis_probe(doc: &str, env: &project::Env) -> Composite {
+    blueprint_axis_probe_reopened(doc, env, &[])
+}
+
+/// The axis probe with a #246 override set re-opened on the strategy BEFORE
+/// wrapping — probe and per-member reloads must re-open identically so points
+/// resolve against one space. The empty-set form is byte-equal to the old
+/// probe (mc/run closed-checks and the open `--list-axes` lines read that).
+fn blueprint_axis_probe_reopened(doc: &str, env: &project::Env, overrides: &[String]) -> Composite {
     let signal = blueprint_from_json(doc, &|t| env.resolve(t))
         .expect("doc parse-validated at the dispatch boundary; reload is infallible");
+    let signal = reopen_all(signal, overrides);
     // The PROBE binding is lenient (unresolvable roles fall back to close),
     // like the probe's synthetic pip: the wrap is built for its param_space
     // only, never run over data — strict resolution lives on the run paths.
@@ -1805,13 +1832,94 @@ fn blueprint_axis_probe(doc: &str, env: &project::Env) -> Composite {
     wrap_r(signal, tx_eq, tx_ex, tx_r, tx_req, StopRule::Vol { length: R_SMA_STOP_LENGTH, k: R_SMA_STOP_K }, true, SYNTHETIC_PIP_SIZE, &probe, None)
 }
 
+/// The override subset of `names` (#246): every name missing the un-reopened
+/// wrapped OPEN space but naming a BOUND param of the strategy — returned in
+/// STRATEGY coordinates (the wrap prefix `<signal.name()>.` stripped) for
+/// `Composite::reopen`. Names matching neither space are skipped here; the
+/// caller decides whether that is an error (sweep boundary) or falls through
+/// to its existing resolution errors. The silent variant `reproduce_family_in`
+/// uses over the RECORDED manifest param names (the sweep boundary uses the
+/// stricter `override_paths`, which errors on an unmatched name instead).
+fn bound_overrides_of(
+    names: &[String],
+    open_space: &[ParamSpec],
+    signal: &Composite,
+) -> Vec<String> {
+    let open: HashSet<&str> = open_space.iter().map(|p| p.name.as_str()).collect();
+    let prefix = format!("{}.", signal.name());
+    let bound: HashSet<String> = signal
+        .bound_param_space()
+        .into_iter()
+        .map(|b| format!("{prefix}{}", b.name))
+        .collect();
+    names
+        .iter()
+        .filter(|n| !open.contains(n.as_str()) && bound.contains(*n))
+        .map(|n| n[prefix.len()..].to_string())
+        .collect()
+}
+
+/// The sweep-boundary variant (#246): like `bound_overrides_of`, but an axis
+/// matching NEITHER the open nor the bound space is the error — the honest
+/// replacement of the retired "fully bound; nothing to sweep" refusal.
+fn override_paths(
+    axes: &[(String, Vec<Scalar>)],
+    open_space: &[ParamSpec],
+    signal: &Composite,
+) -> Result<Vec<String>, String> {
+    let open: HashSet<&str> = open_space.iter().map(|p| p.name.as_str()).collect();
+    let prefix = format!("{}.", signal.name());
+    let bound: HashSet<String> = signal
+        .bound_param_space()
+        .into_iter()
+        .map(|b| format!("{prefix}{}", b.name))
+        .collect();
+    let mut overrides = Vec::new();
+    for (name, _) in axes {
+        if open.contains(name.as_str()) {
+            continue;
+        }
+        if bound.contains(name) {
+            overrides.push(name[prefix.len()..].to_string());
+        } else {
+            return Err(format!(
+                "axis {name}: names no param of this blueprint (open or bound) — \
+                 see `aura sweep <bp> --list-axes`"
+            ));
+        }
+    }
+    Ok(overrides)
+}
+
+/// Apply a validated override set to a freshly loaded strategy (#246).
+/// Infallible by contract: the set was derived against this same document at
+/// the family boundary.
+fn reopen_all(signal: Composite, overrides: &[String]) -> Composite {
+    overrides.iter().fold(signal, |s, p| {
+        s.reopen(p).expect("override set validated at the family boundary")
+    })
+}
+
 /// `aura sweep <blueprint.json> --list-axes`: one `<name>:<kind>` line per open
-/// sweepable knob, in `param_space()` order; a closed blueprint prints nothing.
-/// Names are exactly what `--axis` binds (same probe as the sweep terminal).
+/// sweepable knob, in `param_space()` order (byte-identical to before #246),
+/// followed by one `<name>:<kind> default=<value>` line per BOUND param —
+/// every bound param IS a sweepable default, re-openable by naming it as an
+/// `--axis` (#246), on EVERY blueprint shape (fully open, partially open, or
+/// fully closed) — not only the fully-closed case: `--axis`/`override_paths`
+/// accepts a bound name regardless of how many knobs happen to be open
+/// alongside it, so the discovery surface must list it regardless too. Names
+/// are exactly what `--axis` binds.
 fn list_blueprint_axes(doc: &str, env: &project::Env) {
-    for p in blueprint_axis_probe(doc, env).param_space() {
+    let space = blueprint_axis_probe(doc, env).param_space();
+    for p in &space {
         println!("{}:{:?}", p.name, p.kind); // ScalarKind Debug -> I64/F64/Bool/Timestamp
     }
+    let signal = blueprint_from_json(doc, &|t| env.resolve(t))
+        .expect("doc parse-validated at the dispatch boundary");
+    let bp = signal.name().to_string();
+    for b in signal.bound_param_space() {
+        println!("{bp}.{}:{:?} default={}", b.name, b.kind, render_value(&b.value));
+    }
 }
 
 /// Sweep a serialized signal `doc` over user-named param-space axes. Structurally it
@@ -1823,11 +1931,9 @@ fn list_blueprint_axes(doc: &str, env: &project::Env) {
 /// The axes are taken verbatim BY NAME (not the four suffix-resolved r-sma knobs):
 /// each `(name, vals)` is fed straight to the `SweepBinder`, so an unknown name or a
 /// kind mismatch surfaces as the sweep terminal's [`BindError`], rendered to a message
-/// string — a named error, never a panic. A FULLY BOUND (closed) blueprint has an empty
-/// `param_space` — nothing to sweep — and is refused up front with a clear message
-/// (the symmetric inverse of [`blueprint_mc_family`]'s closed-blueprint requirement),
-/// pre-empting the misleading `UnknownKnob(<axis>)` the per-axis resolve would emit for a
-/// knob that is not unknown but bound out. Every member manifest carries the shared
+/// string — a named error, never a panic. An axis naming a bound param re-opens it
+/// (#246: bound value = default); an axis matching neither space is refused by
+/// `override_paths` before any run. Every member manifest carries the shared
 /// `topology_hash` of the loaded signal; reduce-mode fold, identical to the retired
 /// mirror's default (no-trace) arm.
 fn blueprint_sweep_family(
@@ -1836,14 +1942,11 @@ fn blueprint_sweep_family(
     data: &DataSource,
     env: &project::Env,
 ) -> Result<SweepFamily, String> {
-    // The doc is parse-validated at the dispatch boundary (with file-path context),
-    // so every reload here is infallible: the builder has a single error contract —
-    // the `BindError` returned by the sweep terminal — and no hidden process exit.
-    let reload = |d: &str| {
-        blueprint_from_json(d, &|t| env.resolve(t))
-            .expect("doc parse-validated at the dispatch boundary; reload is infallible")
-    };
-    let probe_signal = reload(doc);
+    // Identity + binding read the AUTHORED doc, raw (no override re-open):
+    // topology and the resolved role plan are properties of the document, not
+    // of any one sweep's axis choices.
+    let probe_signal = blueprint_from_json(doc, &|t| env.resolve(t))
+        .expect("doc parse-validated at the dispatch boundary; reload is infallible");
     let topo = topology_hash(&probe_signal);
     // Strict binding resolution (name defaults — the verb path carries no
     // campaign overrides): the family's open plan and wrap plan in one value.
@@ -1853,23 +1956,26 @@ fn blueprint_sweep_family(
     }
     let pip = data.pip_size();
     let window = data.full_window(env);
-    // a single throwaway floated build, only to resolve param_space (borrow) then seed
-    // the named axes (move) — its taps are never drained. The wrapped probe is the one
-    // `blueprint_axis_probe` single-sources (identical `false, true, None` wrap).
-    let probe = blueprint_axis_probe(doc, env);
+    // The un-reopened wrapped OPEN space (#246): derives the override set (which
+    // named axes re-open a bound param) before the real, reopened probe is built —
+    // probe and per-member reloads must re-open identically so points resolve
+    // against one space. A name matching neither space is the error here.
+    let raw_space = blueprint_axis_probe(doc, env).param_space();
+    let overrides = override_paths(axes, &raw_space, &probe_signal)?;
+    let probe = blueprint_axis_probe_reopened(doc, env, &overrides);
     let space = probe.param_space();
-    // A fully bound blueprint has no open knob — there is nothing to sweep. Refuse it up
-    // front (mirroring blueprint_mc_family's closed-blueprint guard, inverted) BEFORE the
-    // per-axis resolve, which would otherwise return `UnknownKnob(<axis>)` — misleading, as
-    // the named knob is not unknown but bound out. Exit-free: the message is returned for
-    // the IO wrapper to render + exit 2, so the precondition is unit-testable.
-    if space.is_empty() {
-        return Err(
-            "this blueprint is fully bound; nothing to sweep (use `aura sweep <bp> --list-axes` \
-             to confirm there are no open knobs)"
-                .to_string(),
-        );
-    }
+    // The doc is parse-validated at the dispatch boundary (with file-path context),
+    // so every reload here is infallible: the builder has a single error contract —
+    // the `BindError` returned by the sweep terminal — and no hidden process exit.
+    // Member reloads re-open the SAME override set derived above, so every member
+    // resolves its axes against the identical (reopened) param space the probe used.
+    let reload = |d: &str| {
+        reopen_all(
+            blueprint_from_json(d, &|t| env.resolve(t))
+                .expect("doc parse-validated at the dispatch boundary; reload is infallible"),
+            &overrides,
+        )
+    };
     // seed the named axes verbatim: the first via Composite::axis (consumes the probe),
     // the rest via SweepBinder::axis. resolve_axes name- and kind-checks them at the
     // sweep terminal, so an UnknownKnob / KindMismatch is returned, not panicked.
@@ -1894,7 +2000,12 @@ fn blueprint_sweep_family(
 /// `[from,to]` — the windowed, lattice-carrying twin of
 /// `blueprint_sweep_family`. `sweep_with_lattice` gives the grid lattice `--select
 /// plateau` needs. An unknown/kind-mismatched axis surfaces as `BindError` at the
-/// sweep terminal (no panic, no hidden exit) for the caller to render.
+/// sweep terminal (no panic, no hidden exit) for the caller to render. An axis
+/// naming a bound param re-opens it (#246: bound value = default, same
+/// `override_paths`/`reopen_all` recipe as `blueprint_sweep_family` — this is
+/// its walk-forward in-sample twin); an axis matching neither space is refused
+/// (wrapped as `BindError::UnknownKnob`, the honest replacement for the retired
+/// "fully bound; nothing to sweep" refusal) before any member runs.
 fn blueprint_sweep_over(
     doc: &str, axes: &[(String, Vec<Scalar>)], from: Timestamp, to: Timestamp, data: &DataSource,
     env: &project::Env, binding: &binding::ResolvedBinding,
@@ -1904,8 +2015,16 @@ fn blueprint_sweep_over(
             .expect("doc parse-validated at the dispatch boundary; reload is infallible")
     };
     let pip = data.pip_size();
-    let topo = topology_hash(&reload(doc));
-    let probe = blueprint_axis_probe(doc, env);
+    let probe_signal = reload(doc);
+    let topo = topology_hash(&probe_signal);
+    // The un-reopened wrapped OPEN space (#246), against a raw probe + raw strategy
+    // load: derives the override set (which named axes re-open a bound param) before
+    // the reopened probe is built — probe and per-member reloads must re-open
+    // identically so points resolve against one space, exactly like
+    // `blueprint_sweep_family`.
+    let raw_space = blueprint_axis_probe(doc, env).param_space();
+    let overrides = override_paths(axes, &raw_space, &probe_signal).map_err(BindError::UnknownKnob)?;
+    let probe = blueprint_axis_probe_reopened(doc, env, &overrides);
     let space = probe.param_space();
     let mut iter = axes.iter();
     let (first_name, first_vals) = iter.next().expect("a blueprint walk-forward declares >= 1 axis");
@@ -1916,21 +2035,29 @@ fn blueprint_sweep_over(
     binder.sweep_with_lattice(|point| {
         let sources = data.windowed_sources(from, to, env, &binding.columns());
         let window = window_of(&sources).expect("non-empty in-sample window");
-        run_blueprint_member(reload(doc), point, &space, sources, window, 0, pip, &topo, env, StopRule::Vol { length: R_SMA_STOP_LENGTH, k: R_SMA_STOP_K }, binding, &[])
+        run_blueprint_member(reopen_all(reload(doc), &overrides), point, &space, sources, window, 0, pip, &topo, env, StopRule::Vol { length: R_SMA_STOP_LENGTH, k: R_SMA_STOP_K }, binding, &[])
     })
 }
 
 /// Run the winner params over an out-of-sample window `[from,to]` on the loaded
 /// blueprint. The reduce-mode member
 /// (`run_blueprint_member`) retains R-metrics, not a raw pip curve, so the stitching
-/// segment is empty (an empty segment leaves the stitched curve unbroken).
+/// segment is empty (an empty segment leaves the stitched curve unbroken). `overrides`
+/// (#246) is the SAME family-wide set `blueprint_walkforward_family` derived once and
+/// resolved `space`/`params` against — the OOS reload must re-open it too, or a
+/// bound-param axis's winner point (kind-checked against the REOPENED space) fails
+/// `bootstrap_with_cells`'s arity check against this still-closed reload.
 #[allow(clippy::too_many_arguments)]
 fn run_oos_blueprint(
     doc: &str, params: &[Cell], space: &[ParamSpec], from: Timestamp, to: Timestamp,
     topo: &str, data: &DataSource, env: &project::Env, binding: &binding::ResolvedBinding,
+    overrides: &[String],
 ) -> (Vec<(Timestamp, f64)>, RunReport) {
-    let reload = blueprint_from_json(doc, &|t| env.resolve(t))
-        .expect("doc parse-validated at the dispatch boundary; reload is infallible");
+    let reload = reopen_all(
+        blueprint_from_json(doc, &|t| env.resolve(t))
+            .expect("doc parse-validated at the dispatch boundary; reload is infallible"),
+        overrides,
+    );
     let pip = data.pip_size();
     let sources = data.windowed_sources(from, to, env, &binding.columns());
     let window = window_of(&sources).expect("non-empty out-of-sample window");
@@ -1956,10 +2083,22 @@ fn blueprint_walkforward_family(
             std::process::exit(2);
         }
     };
-    let space = blueprint_axis_probe(doc, env).param_space();
     let probe_signal = blueprint_from_json(doc, &|t| env.resolve(t))
         .expect("doc parse-validated at the dispatch boundary; reload is infallible");
     let topo = topology_hash(&probe_signal);
+    // The un-reopened wrapped OPEN space (#246), against a raw probe + raw strategy
+    // load: derives the override set ONCE for the whole family — every per-window
+    // sweep AND the OOS reload re-open the SAME set, mirroring
+    // `blueprint_sweep_family`/`blueprint_sweep_over`. The SILENT variant
+    // (`bound_overrides_of`, not the validating `override_paths`): an axis matching
+    // neither space is simply not an override here — the strict check + its
+    // established error message stay single-sourced in `blueprint_sweep_over`'s own
+    // pre-flight call below, so this derivation cannot double-validate with a
+    // differently-worded rejection.
+    let axis_names: Vec<String> = axes.iter().map(|(n, _)| n.clone()).collect();
+    let raw_space = blueprint_axis_probe(doc, env).param_space();
+    let overrides = bound_overrides_of(&axis_names, &raw_space, &probe_signal);
+    let space = blueprint_axis_probe_reopened(doc, env, &overrides).param_space();
     // Strict binding resolution, once per family; refusal is the established
     // `aura: ` + exit-1 register (the roller's usage refusals stay exit 2).
     let binding = binding::resolve_binding(probe_signal.name(), probe_signal.input_roles(), &BTreeMap::new())
@@ -1995,7 +2134,7 @@ fn blueprint_walkforward_family(
             Err(msg) => { eprintln!("aura: {msg}"); std::process::exit(2); }
         };
         let (oos_equity, mut oos_report) =
-            run_oos_blueprint(doc, &best.params, &space, w.oos.0, w.oos.1, &topo, data, env, &binding);
+            run_oos_blueprint(doc, &best.params, &space, w.oos.0, w.oos.1, &topo, data, env, &binding, &overrides);
         oos_report.manifest.selection = Some(selection);
         WindowRun { chosen_params: best.params, oos_equity, oos_report }
     })
@@ -5311,36 +5450,34 @@ mod tests {
         let _ = std::fs::remove_dir_all(&dir);
     }
 
-    /// Property: sweeping a FULLY BOUND (closed) blueprint is refused up front with a
-    /// clear "fully bound / nothing to sweep" message — NOT the terse `UnknownKnob(<axis>)`
-    /// the per-axis resolve would otherwise emit (misleading: the named knob is not unknown,
-    /// it is bound out, so there is simply nothing to sweep). Symmetric inverse of
-    /// `blueprint_mc_family_rejects_an_open_blueprint` (mc requires a closed blueprint; a
-    /// sweep requires >= 1 open knob). Type-agnostic on the error (renders it via Debug), so
-    /// the RED phase compiles whether the builder returns a `BindError` or a `String`.
+    /// #246: a fully-bound (closed) blueprint IS sweepable — an axis naming a
+    /// bound param re-opens it (the bound value is the default), so the retired
+    /// "fully bound; nothing to sweep" refusal must not resurface. Inverse
+    /// guard: an axis naming NEITHER an open nor a bound param gets the one
+    /// clear boundary message (not a terse `UnknownKnob` debug leak).
     #[test]
-    fn blueprint_sweep_family_rejects_a_fully_bound_blueprint() {
+    fn blueprint_sweep_family_overrides_a_bound_param_and_names_unknown_axes() {
         let env = project::Env::std();
-        // both SMA knobs bound -> empty param_space
+        // same fixture the retired test swept: both SMA knobs bound.
         let closed = load_closed_r_sma();
         let doc = blueprint_to_json(&closed).expect("serializes");
-        // an axis naming a bound-out knob: the pre-fix path returns UnknownKnob for it.
+
+        // (a) override axis: two members, no refusal
         let axes = vec![(
-            "sma_signal.slow.length".to_string(),
-            vec![Scalar::i64(4), Scalar::i64(6)],
+            "sma_signal.fast.length".to_string(),
+            vec![Scalar::i64(2), Scalar::i64(4)],
         )];
-        let err = match blueprint_sweep_family(&doc, &axes, &DataSource::Synthetic, &env) {
-            Ok(_) => panic!("a fully-bound blueprint has nothing to sweep"),
-            Err(e) => format!("{e:?}"),
-        };
-        assert!(
-            err.contains("fully bound") || err.contains("nothing to sweep"),
-            "names the fully-bound / nothing-to-sweep condition: {err}"
-        );
-        assert!(
-            !err.contains("UnknownKnob"),
-            "must not leak the misleading UnknownKnob: {err}"
-        );
+        let fam = blueprint_sweep_family(&doc, &axes, &DataSource::Synthetic, &env)
+            .expect("a bound param is a default — the axis overrides it");
+        assert_eq!(fam.points.len(), 2);
+
+        // (b) unknown axis: the boundary message, no UnknownKnob leak
+        let bad = vec![("sma_signal.nope".to_string(), vec![Scalar::i64(1)])];
+        let err = blueprint_sweep_family(&doc, &bad, &DataSource::Synthetic, &env)
+            .expect_err("an axis matching neither space is refused");
+        assert!(err.contains("names no param"), "boundary message, got: {err}");
+        assert!(err.contains("--list-axes"), "must point at --list-axes: {err}");
+        assert!(!err.contains("UnknownKnob"), "must not leak the debug render: {err}");
     }
 
     /// Property: an MC family's `aura reproduce` lines carry the member's own `seed=<N>`

crates/aura-cli/tests/cli_run.rs

@@ -1401,9 +1401,12 @@ fn sweep_real_ohlc_channel_members_run_and_reproduce() {
         .output()
         .unwrap();
     assert_eq!(
-        String::from_utf8_lossy(&axes.stdout).trim(),
-        "hl_channel.channel_length:I64",
-        "the ganged channel knob is the one sweepable axis; stderr: {}",
+        String::from_utf8_lossy(&axes.stdout),
+        "hl_channel.channel_length:I64\n\
+         hl_channel.prev_high.lag:I64 default=1\n\
+         hl_channel.prev_low.lag:I64 default=1\n",
+        "the ganged channel knob is the one open axis, alongside the fixture's \
+         bound Delay lags as #246 defaults; stderr: {}",
         String::from_utf8_lossy(&axes.stderr)
     );
     let out = std::process::Command::new(BIN)
@@ -1813,6 +1816,105 @@ fn reproduce_real_sweep_family_re_derives_bit_identically() {
     );
 }
 
+/// Property (C18/C1 reproduce guarantee, #246): the same reproduce guarantee holds
+/// when the swept axis names a BOUND param of a CLOSED starter blueprint, not an
+/// already-open one — `r_sma.json` (both `sma_signal.fast.length` and
+/// `sma_signal.slow.length` bound), the closed counterpart of the OPEN
+/// `r_sma_open.json` the walk-forward reproduce sibling
+/// (`aura_walkforward_over_a_blueprint_reproduces_bit_identically`) sweeps.
+/// Modelled on that sibling (synthetic in-process walk-forward — no `--real`),
+/// NOT on `reproduce_real_sweep_family_re_derives_bit_identically`: a real-data
+/// mint routes through the campaign executor (`CliMemberRunner::run_member` +
+/// `validate_and_register_axes`), neither of which carries any #246 override
+/// threading — a gap outside this task's file scope (`blueprint_sweep_over`,
+/// `reproduce_family_in`) and spanning all four dispatch verbs, so exercising
+/// it here would silently expand into unrelated, unreviewed surface. The
+/// synthetic walk-forward path exercises exactly the threaded functions:
+/// `blueprint_sweep_over` (via `blueprint_walkforward_family`) re-opens
+/// `sma_signal.fast.length` for the per-window IS re-fit, and
+/// `reproduce_family_in` re-opens it again from the recorded manifest params
+/// so the re-derivation resolves against the same space the mint used.
+#[test]
+fn reproduce_family_with_overridden_bound_param_re_derives() {
+    let cwd = temp_cwd("walkforward-reproduce-override");
+    let bp = format!("{}/examples/r_sma.json", env!("CARGO_MANIFEST_DIR"));
+    let run = std::process::Command::new(env!("CARGO_BIN_EXE_aura"))
+        .args(["walkforward", &bp, "--axis", "sma_signal.fast.length=2,3", "--name", "wfo"])
+        .current_dir(&cwd)
+        .output()
+        .expect("spawn aura walkforward");
+    assert_eq!(
+        run.status.code(),
+        Some(0),
+        "walk-forward over a bound-param axis must succeed (#246 re-open), stderr: {}",
+        String::from_utf8_lossy(&run.stderr)
+    );
+    let repro = std::process::Command::new(env!("CARGO_BIN_EXE_aura"))
+        .args(["reproduce", "wfo-0"])
+        .current_dir(&cwd)
+        .output()
+        .expect("spawn aura reproduce");
+    assert_eq!(
+        repro.status.code(),
+        Some(0),
+        "reproduce stderr: {}",
+        String::from_utf8_lossy(&repro.stderr)
+    );
+    let out = String::from_utf8(repro.stdout).expect("utf-8");
+    assert!(
+        out.contains("reproduced 3/3 members bit-identically"),
+        "every OOS member of a deterministic walk-forward over a bound-param axis \
+         re-derives bit-identically: {out}"
+    );
+    let _ = std::fs::remove_dir_all(&cwd);
+}
+
+/// Property (#246, distinct code path from `reproduce_family_with_overridden_bound_param_re_derives`):
+/// `reproduce_family_in`'s override derivation (`bound_overrides_of`, computed once
+/// per family from the FIRST member's recorded params) applies uniformly across
+/// `FamilyKind`s, not only `WalkForward` — a plain `aura sweep` family minted by
+/// overriding a bound param on the CLOSED `r_sma.json` fixture re-derives
+/// bit-identically too. The sibling test exercises `FamilyKind::WalkForward`'s
+/// branch (per-window OOS reload via `run_oos_blueprint`); this one exercises the
+/// `Sweep`-kind branch (`data.run_sources`/`data.full_window`, no per-window
+/// re-fit) of the same shared dispatch in `reproduce_family_in`. A regression that
+/// threaded the #246 override set through one branch but not the other would pass
+/// the walk-forward sibling while failing here.
+#[test]
+fn aura_reproduce_re_derives_a_sweep_family_minted_over_a_bound_param_override() {
+    let cwd = temp_cwd("sweep-reproduce-bound-override");
+    let bp = format!("{}/examples/r_sma.json", env!("CARGO_MANIFEST_DIR"));
+    let sweep = Command::new(BIN)
+        .args(["sweep", &bp, "--axis", "sma_signal.fast.length=2,3", "--name", "swo"])
+        .current_dir(&cwd)
+        .output()
+        .expect("spawn aura sweep over a bound-param axis");
+    assert_eq!(
+        sweep.status.code(),
+        Some(0),
+        "sweeping a bound param of a closed blueprint must succeed (#246 re-open), stderr: {}",
+        String::from_utf8_lossy(&sweep.stderr)
+    );
+    let repro = Command::new(BIN)
+        .args(["reproduce", "swo-0"])
+        .current_dir(&cwd)
+        .output()
+        .expect("spawn aura reproduce");
+    assert_eq!(
+        repro.status.code(),
+        Some(0),
+        "reproduce stderr: {}",
+        String::from_utf8_lossy(&repro.stderr)
+    );
+    let out = String::from_utf8(repro.stdout).expect("utf-8");
+    assert!(
+        out.contains("reproduced 2/2 members bit-identically"),
+        "every member of a plain sweep minted over a bound-param override \
+         re-derives bit-identically: {out}"
+    );
+    let _ = std::fs::remove_dir_all(&cwd);
+}
+
 /// Property: `aura reproduce` yields a handled outcome — a reproduction verdict
 /// or a clean `aura:` refusal — for a real-data WalkForward family, and NEVER an
 /// internal panic. A WalkForward member's OOS window is stored as real epoch-ns
@@ -4385,10 +4487,14 @@ fn aura_reproduce_rejects_a_missing_stored_blueprint() {
     let _ = std::fs::remove_dir_all(&cwd);
 }
 
-/// E2E (#169): `aura sweep <open blueprint.json> --list-axes` prints one
-/// `<name>:<kind>` line per open sweepable knob, in `param_space()` order, and
-/// exits 0. The names are prefixed by the wrapping (sma_signal.*) — exactly
-/// the strings `--axis` binds — so a user can discover then sweep without guessing.
+/// E2E (#169/#246): `aura sweep <open blueprint.json> --list-axes` prints one
+/// `<name>:<kind>` line per open sweepable knob, in `param_space()` order,
+/// followed by one `<name>:<kind> default=<value>` line per BOUND param (the
+/// fixture's `bias.scale` stays bound even though the two SMA lengths are
+/// open — #246's discovery surface lists bound params on EVERY blueprint
+/// shape, not only a fully-closed one), and exits 0. The names are prefixed
+/// by the wrapping (sma_signal.*) — exactly the strings `--axis` binds — so a
+/// user can discover then sweep or re-open without guessing.
 #[test]
 fn aura_sweep_list_axes_prints_prefixed_names() {
     let bp = format!("{}/examples/r_sma_open.json", env!("CARGO_MANIFEST_DIR"));
@@ -4398,20 +4504,35 @@ fn aura_sweep_list_axes_prints_prefixed_names() {
         .expect("spawn aura sweep --list-axes");
     assert_eq!(out.status.code(), Some(0));
     let stdout = String::from_utf8(out.stdout).expect("utf-8");
-    assert_eq!(stdout, "sma_signal.fast.length:I64\nsma_signal.slow.length:I64\n");
+    assert_eq!(
+        stdout,
+        "sma_signal.fast.length:I64\n\
+         sma_signal.slow.length:I64\n\
+         sma_signal.bias.scale:F64 default=0.5\n"
+    );
 }
 
-/// E2E (#169): `--list-axes` on a CLOSED blueprint (all knobs bound) prints
-/// nothing and exits 0 — an empty axis set is the honest answer, not an error.
+/// E2E (#246): `--list-axes` on a CLOSED blueprint (all knobs bound) prints one
+/// `<bp>.<node>.<param>:<KIND> default=<value>` line per bound param — the
+/// bound value IS the default, overridable by naming the same path as an
+/// `--axis` (#246's re-open contract) — and exits 0. The sibling pin above
+/// (`aura_sweep_list_axes_prints_prefixed_names`) proves the same bound-param
+/// lines also appear on a PARTIALLY open blueprint, after its open lines.
 #[test]
-fn aura_sweep_list_axes_closed_is_empty() {
+fn aura_sweep_list_axes_closed_prints_bound_defaults() {
     let bp = format!("{}/examples/r_sma.json", env!("CARGO_MANIFEST_DIR"));
     let out = std::process::Command::new(env!("CARGO_BIN_EXE_aura"))
         .args(["sweep", &bp, "--list-axes"])
         .output()
         .expect("spawn aura sweep --list-axes (closed)");
     assert_eq!(out.status.code(), Some(0));
-    assert!(out.stdout.is_empty(), "a closed blueprint has no open axes");
+    let stdout = String::from_utf8(out.stdout).expect("utf-8");
+    assert_eq!(
+        stdout,
+        "sma_signal.fast.length:I64 default=2\n\
+         sma_signal.slow.length:I64 default=4\n\
+         sma_signal.bias.scale:F64 default=0.5\n"
+    );
 }
 
 /// E2E (#169): `--list-axes` is a standalone query — combining it with a real
@@ -4510,26 +4631,48 @@ fn aura_sweep_list_axes_names_round_trip_into_a_working_sweep() {
     let cwd = temp_cwd("blueprint-list-axes-roundtrip");
     let bp = format!("{}/examples/r_sma_open.json", env!("CARGO_MANIFEST_DIR"));
 
-    // 1) discover the axis names (do NOT hardcode them) — this is what a user reads.
+    // 1) discover the axis names + kinds (do NOT hardcode them) — this is what a user
+    //    reads. #246: the fixture now lists a BOUND param (`bias.scale`, F64) alongside
+    //    the two open I64 lengths, so the CSV below must be typed per discovered kind,
+    //    not assumed integer.
     let list = Command::new(BIN)
         .args(["sweep", &bp, "--list-axes"])
         .output()
         .expect("spawn aura sweep --list-axes");
     assert_eq!(list.status.code(), Some(0));
     let listed = String::from_utf8(list.stdout).expect("utf-8");
-    let names: Vec<String> = listed
+    let names: Vec<(String, String)> = listed
         .lines()
-        .map(|l| l.split(':').next().expect("a `name:kind` line").to_string())
+        .map(|l| {
+            let mut parts = l.splitn(2, ':');
+            let name = parts.next().expect("a `name:kind` line").to_string();
+            let kind = parts
+                .next()
+                .expect("kind after ':'")
+                .split_whitespace()
+                .next()
+                .expect("a kind token")
+                .to_string();
+            (name, kind)
+        })
         .collect();
     assert!(!names.is_empty(), "the open fixture must list >= 1 axis");
 
     // 2) feed the DISCOVERED names straight back into a real sweep. Values are
     //    position-assigned (first axis small, rest large) to stay in a non-degenerate
-    //    SMA regime without re-hardcoding the names; each axis takes two values.
+    //    SMA regime without re-hardcoding the names; each axis takes two values, typed
+    //    per its discovered kind so a bound F64 default (e.g. `bias.scale`) resolves
+    //    instead of tripping `KindMismatch` on an integer-shaped token.
     let mut args: Vec<String> = vec!["sweep".into(), bp.clone()];
-    for (i, name) in names.iter().enumerate() {
+    for (i, (name, kind)) in names.iter().enumerate() {
+        let vals: &str = match (i == 0, kind.as_str()) {
+            (true, "F64") => "2.0,4.0",
+            (true, _) => "2,4",
+            (false, "F64") => "8.0,16.0",
+            (false, _) => "8,16",
+        };
         args.push("--axis".into());
-        args.push(format!("{name}={}", if i == 0 { "2,4" } else { "8,16" }));
+        args.push(format!("{name}={vals}"));
     }
     let sweep = Command::new(BIN)
         .args(&args)

crates/aura-cli/tests/project_sweep_campaign.rs

@@ -152,9 +152,12 @@ fn fresh_project() -> (&'static PathBuf, (RunsCleanup, MutexGuard<'static, ()>))
 fn project_node_open_param_sweeps_and_reproduces() {
     let (dir, _g) = fresh_project();
 
-    // (a) `--list-axes` discovers the PROJECT node's own open knob. NOT gated:
-    // enumerating axes needs no data, so the discoverability half runs on every
-    // host. The wrapped name is `<blueprint>.<node>.<param>`.
+    // (a) `--list-axes` discovers the PROJECT node's own open knob, followed by
+    // the fixture's three BOUND params as `default=`-lines (#246: every bound
+    // param is an equally re-openable `--axis`, listed regardless of how many
+    // knobs happen to be open alongside it). NOT gated: enumerating axes needs
+    // no data, so the discoverability half runs on every host. The wrapped
+    // name is `<blueprint>.<node>.<param>`.
     let axes = aura_in(dir, &["sweep", "blueprints/scaled_open.json", "--list-axes"]);
     assert!(
         axes.status.success(),
@@ -162,9 +165,13 @@ fn project_node_open_param_sweeps_and_reproduces() {
         String::from_utf8_lossy(&axes.stderr)
     );
     assert_eq!(
-        String::from_utf8_lossy(&axes.stdout).trim(),
-        "scaled_signal.gain.factor:F64",
-        "the project node's own param is the one discoverable sweep axis; stderr: {}",
+        String::from_utf8_lossy(&axes.stdout),
+        "scaled_signal.gain.factor:F64\n\
+         scaled_signal.fast.length:I64 default=2\n\
+         scaled_signal.slow.length:I64 default=4\n\
+         scaled_signal.bias.scale:F64 default=0.5\n",
+        "the project node's own OPEN param is the one open axis, alongside the \
+         fixture's bound defaults; stderr: {}",
         String::from_utf8_lossy(&axes.stderr)
     );