fix(sampler): JoyAI-Echo overwrote the i2v anchor on H3

H3 keys keyframe pins by frame index and takes only first/last, so memory
frame 0 evicted the anchor and the rest were refused. Forced off with a
reason; hidden in Engine Settings. Tooltips now state the LoRA requirement.

CHANGELOG.md

@@ -99,6 +99,16 @@
   looked exactly like one where the feature was switched off.
 
 ### Fixed
+- **JoyAI-Echo is switched off and hidden on MiniMax H3, where it was doing damage.** The
+  memory bank places frame *i* at sequence position *i*, but H3's packed layout pins only the
+  first or last frame — so every frame past the first was refused, and the one that landed
+  *replaced the scene's i2v anchor*, because H3 keys pins by frame index. Not an inert toggle:
+  a harmful one. The sampler now forces it off on H3 and says why, and Engine Settings stops
+  offering the whole group.
+- **JoyAI-Echo's tooltips now say it requires the JoyAI-Echo LoRA.** Without it the injected
+  memory frames change nothing on any model, because the base weights were never trained to
+  read them as memory — the controls read as a working feature.
+
 - **Closing Models & Pipeline mid-edit no longer leaves its edit buffer behind.** Escape, the
   ✕, or switching to another section tore the section down without ending the edit, so the
   next visit inherited a dirty flag and a baseline belonging to a config that had already

movie_editor/frontend/pipeline_caps.js

@@ -128,8 +128,19 @@
     bounded_attention_enabled:
       "Bounded Attention masks text cross-attention; H3 puts text in the same self-attention "
       + "stream as the video, where the mask would be far too large to hold.",
+    joyai_memory:
+      "JoyAI-Echo places memory frame i at sequence position i. H3's packed layout pins only "
+      + "the FIRST or LAST frame, so every frame past the first is refused — and the one that "
+      + "lands replaces the scene's i2v anchor, because pins are keyed by frame index. This "
+      + "one is not merely inert on H3, it is harmful, so the sampler forces it off.",
   };
 
+  // JoyAI's own sub-settings: they configure a bank that cannot be built here.
+  const JOYAI_SUB_INPUTS = [
+    "joyai_memory_size", "joyai_fix_frames", "joyai_frame_select", "joyai_memory_strength",
+    "joyai_audio_memory",
+  ];
+
   // Same idea for non-boolean knobs whose neutral value means "off".
   // The latent ops (second_pass_op, segmented detailing) are NOT listed here any more: what
   // they need is an upsampler whose latents are the same width as the model's, which depends
@@ -171,7 +182,7 @@
     if (!usesChainSampler(st)) return new Set();
     if (!isH3(st)) return new Set(Object.keys(H3_ONLY_SAMPLER_INPUTS));
     return new Set([...Object.keys(H3_DEAD_SAMPLER_INPUTS), ...IDENTITY_SUB_INPUTS,
-                    ...H3_DEAD_VALUE_INPUTS]);
+                    ...JOYAI_SUB_INPUTS, ...H3_DEAD_VALUE_INPUTS]);
   }
 
   // Returns [{short, detail}] for settings that are ON but cannot do anything on H3.

movie_editor/frontend/pipeline_caps.test.js

@@ -26,11 +26,13 @@ test("H3 hides identity transfer's sub-settings with it, not just the toggle", (
   }
 });
 
-test("H3 hides v2a_grad_scale but keeps the feature it couples to", () => {
+test("H3 hides the whole JoyAI group, coupling knob included", () => {
+  // This used to assert the opposite for joyai_audio_memory, on the reading that only the
+  // LTXAV coupling knob was dead. That was wrong: the VIDEO half does not work on H3
+  // either, and audio memory is gated on it, so nothing in the group can function.
   const inert = PC.familyInertInputs(h3);
   assert.ok(inert.has("v2a_grad_scale"));
-  // JoyAI audio memory itself works on H3 — only the LTXAV coupling knob is dead.
-  assert.ok(!inert.has("joyai_audio_memory"));
+  assert.ok(inert.has("joyai_audio_memory"));
 });
 
 test("LTX hides the H3-only audio clock", () => {
@@ -70,3 +72,24 @@ test("the main-window chips no longer name a control that is now hidden", () =>
   assert.ok(!chips.some((c) => /can't run/.test(c.short)),
     "a hidden setting should not also be chipped");
 });
+
+// ── JoyAI-Echo is hidden on H3 ────────────────────────────────────────────────
+// Not because it fails to fire, but because it fires and does the wrong thing: H3 keys
+// keyframe pins by frame index and accepts only the first or last, so the one memory frame
+// that lands REPLACES the scene's i2v anchor and the rest are refused.
+
+test("every JoyAI control disappears on H3", () => {
+  const inert = PC.familyInertInputs(h3);
+  for (const k of ["joyai_memory", "joyai_memory_size", "joyai_fix_frames",
+                   "joyai_frame_select", "joyai_memory_strength", "joyai_audio_memory",
+                   "v2a_grad_scale"]) {
+    assert.ok(inert.has(k), `${k} should be hidden on H3`);
+  }
+});
+
+test("JoyAI stays available on LTX", () => {
+  const inert = PC.familyInertInputs(ltx);
+  for (const k of ["joyai_memory", "joyai_memory_size", "joyai_audio_memory"]) {
+    assert.ok(!inert.has(k), `${k} must remain reachable on LTX`);
+  }
+});

samplers.py

@@ -2740,7 +2740,7 @@ class FunPackLTXAVSceneChainSampler:
                 # mapping and lands a numeric on a combo (e.g. joyai_frame_select got 0).
                 "joyai_memory": ("BOOLEAN", {
                     "default": False,
-                    "tooltip": "JoyAI-Echo cross-shot memory bank. Generalizes mid_scene_guide from one anchor to a managed set of clean prior-shot frames injected into each scene via LTX guide attention, so character/scene identity carries across the whole chain (JoyAI-Echo's story-level consistency). The first joyai_fix_frames scenes are pinned permanently as a global anchor; the rest is a rolling most-recent window capped at joyai_memory_size. Supersedes mid_scene_guide when on. Video memory only; pair it with joyai_audio_memory for the soundtrack.",
+                    "tooltip": "JoyAI-Echo cross-shot memory bank. REQUIRES the JoyAI-Echo LoRA — without it the injected memory frames change nothing, because the base model was never trained to read them as memory. Generalizes mid_scene_guide from one anchor to a managed set of clean prior-shot frames injected into each scene via LTX guide attention, so character/scene identity carries across the whole chain (JoyAI-Echo's story-level consistency). The first joyai_fix_frames scenes are pinned permanently as a global anchor; the rest is a rolling most-recent window capped at joyai_memory_size. Supersedes mid_scene_guide when on. Video memory only; pair it with joyai_audio_memory for the soundtrack.",
                 }),
                 "joyai_memory_size": ("INT", {
                     "default": 7, "min": 1, "max": 32,
@@ -2762,7 +2762,7 @@ class FunPackLTXAVSceneChainSampler:
                 # builder's positional reference-workflow mapping (extract_widgets) stays aligned.
                 "joyai_audio_memory": ("BOOLEAN", {
                     "default": False,
-                    "tooltip": "JoyAI-Echo PAIRED AUDIO memory. Alongside each video memory frame, pin the prior shot's clean audio latent into the audio stream so voice/timbre/ambience carry across shots the way the face now does. Deliberately breaks the audio pass-through invariant — off by default. Requires joyai_memory on; no effect on single-stream (video-only) LTXV.",
+                    "tooltip": "JoyAI-Echo PAIRED AUDIO memory. Needs the JoyAI-Echo LoRA, like the video memory it accompanies. Alongside each video memory frame, pin the prior shot's clean audio latent into the audio stream so voice/timbre/ambience carry across shots the way the face now does. Deliberately breaks the audio pass-through invariant — off by default. Requires joyai_memory on; no effect on single-stream (video-only) LTXV.",
                 }),
                 "v2a_grad_scale": ("FLOAT", {
                     "default": 1.0, "min": 0.0, "max": 4.0, "step": 0.25,
@@ -6680,6 +6680,12 @@ class FunPackLTXAVSceneChainSampler:
                              "against LTX's 4096-wide cross-attention context, and the overlap "
                              "tokens need LTX's patchifier; H3's native ref2va reference blocks "
                              "are the equivalent and are not wired yet)")
+            if joyai_memory:
+                _dead.append("joyai_memory / JoyAI-Echo (the memory bank places frame i at "
+                             "sequence position i, and H3's packed layout pins only the FIRST "
+                             "or LAST frame — so every frame past the first is refused, and "
+                             "the one that lands REPLACES the scene's i2v anchor, since pins "
+                             "are keyed by frame index. Not inert on H3: harmful)")
             # Gated on joyai_audio_memory, not on the value alone: v2a_grad_scale is that
             # feature's coupling knob and is never installed without it (see the call site),
             # so reporting a left-over value as an H3 limitation blames the model for a knob
@@ -6698,6 +6704,11 @@ class FunPackLTXAVSceneChainSampler:
             # that dies three minutes in is worse than a knob that says why it is inert.
             bounded_attention_enabled = False
             identity_transfer_enabled = False
+            # Off for real, not merely hidden in the UI: unlike the two above, this one does
+            # not fail to fire — it fires and overwrites the anchor pin. A stored value from
+            # an LTX project must not keep doing that here.
+            joyai_memory = False
+            joyai_audio_memory = False
             v2a_grad_scale = 1.0
             # second_pass_op is NOT switched off here. It only needs a latent upsampler that
             # matches this model's latent width; which file that is depends on what is