diff --git a/docs/canvas-lab-architecture.md b/docs/canvas-lab-architecture.md
index f5acbd1ab5..343ecf6608 100644
--- a/docs/canvas-lab-architecture.md
+++ b/docs/canvas-lab-architecture.md
@@ -228,6 +228,7 @@ Current safe flow:
 - dialog passes options -> registry -> block dialogs (`LlmDialog`, `ModelConfigDialog`, `TimedeltaDialog`)
 
 No dialog component should import store directly.
+Exception: read-only derived data (e.g. `available-variables.tsx` reads `configs` for variable list).
 
 ## 9) Add New Block (exact flow)
 
diff --git a/studio/frontend/src/features/canvas-lab/components/canvas-aux-node.tsx b/studio/frontend/src/features/canvas-lab/components/canvas-aux-node.tsx
index 2c531a432c..1da19b939f 100644
--- a/studio/frontend/src/features/canvas-lab/components/canvas-aux-node.tsx
+++ b/studio/frontend/src/features/canvas-lab/components/canvas-aux-node.tsx
@@ -1,3 +1,4 @@
+import { Badge } from "@/components/ui/badge";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
 import { Textarea } from "@/components/ui/textarea";
@@ -13,6 +14,7 @@ import { MAX_NODE_WIDTH, MIN_NODE_WIDTH } from "../constants";
 import { useCanvasLabStore } from "../stores/canvas-lab";
 import type { LayoutDirection, LlmConfig, Score, ScoreOption } from "../types";
 import { HANDLE_IDS } from "../utils/handles";
+import { getAvailableVariables } from "../utils/variables";
 import { BaseNode, BaseNodeContent, BaseNodeHeader, BaseNodeHeaderTitle } from "./rf-ui/base-node";
 
 type PromptField = "prompt" | "system_prompt";
@@ -56,6 +58,28 @@ function updateOptionAt(
   );
 }
 
+function AuxVariableBadges({ llmId }: { llmId: string }): ReactElement | null {
+  const configs = useCanvasLabStore((state) => state.configs);
+  const vars = getAvailableVariables(configs, llmId);
+  if (vars.length === 0) return null;
+  return (
+    <div className="space-y-1">
+      <p className="text-[10px] font-medium text-muted-foreground">Available references</p>
+      <div className="flex flex-wrap gap-1">
+        {vars.map((v) => (
+          <Badge
+            key={v}
+            variant="secondary"
+            className="corner-squircle h-4 px-1.5 font-mono text-[10px]"
+          >
+            {v}
+          </Badge>
+        ))}
+      </div>
+    </div>
+  );
+}
+
 function AuxNodeBase({
   data,
 }: NodeProps<CanvasAuxNodeType>): ReactElement | null {
@@ -88,9 +112,9 @@ function AuxNodeBase({
         <BaseNodeHeader className="border-b border-border/50 px-3 py-2">
           <BaseNodeHeaderTitle className="text-xs">{data.title}</BaseNodeHeaderTitle>
         </BaseNodeHeader>
-        <BaseNodeContent className="px-3 py-2">
+        <BaseNodeContent className="gap-2 px-3 py-2">
           <Textarea
-            className="nodrag max-h-40 min-h-[88px] w-full resize-none overflow-y-auto text-xs"
+            className="corner-squircle nodrag max-h-40 min-h-[88px] w-full resize-none overflow-y-auto text-xs"
             value={value}
             onChange={(event) =>
               updateConfig(data.llmId, {
@@ -98,6 +122,7 @@ function AuxNodeBase({
               } as Partial<LlmConfig>)
             }
           />
+          <AuxVariableBadges llmId={data.llmId} />
         </BaseNodeContent>
         <Handle
           id={HANDLE_IDS.llmInputOut}
@@ -178,7 +203,7 @@ function AuxNodeBase({
           onChange={(event) => updateScore({ name: event.target.value })}
         />
         <Textarea
-          className="nodrag max-h-32 min-h-[56px] w-full resize-none overflow-y-auto text-xs"
+          className="corner-squircle nodrag max-h-32 min-h-[56px] w-full resize-none overflow-y-auto text-xs"
           placeholder="Score description"
           value={score.description}
           onChange={(event) => updateScore({ description: event.target.value })}
diff --git a/studio/frontend/src/features/canvas-lab/components/canvas-node.tsx b/studio/frontend/src/features/canvas-lab/components/canvas-node.tsx
index 858a60557e..37c329af40 100644
--- a/studio/frontend/src/features/canvas-lab/components/canvas-node.tsx
+++ b/studio/frontend/src/features/canvas-lab/components/canvas-node.tsx
@@ -35,6 +35,7 @@ import type {
   SamplerType,
 } from "../types";
 import { getLlmJudgeScoreHandleId, HANDLE_IDS } from "../utils/handles";
+import { InlineCategoryBadges } from "./inline/inline-category-badges";
 import { InlineExpression } from "./inline/inline-expression";
 import { InlineLlm } from "./inline/inline-llm";
 import { InlineModel } from "./inline/inline-model";
@@ -165,48 +166,33 @@ function getConfigSummary(config: NodeConfig | undefined): string {
   return "Open details for config";
 }
 
-function renderInlineEditor(
+function renderNodeBody(
   config: NodeConfig | undefined,
+  summary: string,
   updateConfig: (id: string, patch: Partial<NodeConfig>) => void,
-): ReactElement | null {
-  if (!config || !isInlineConfig(config)) {
-    return null;
+): ReactElement {
+  if (config && isInlineConfig(config)) {
+    const onUpdate = (patch: Partial<NodeConfig>) => updateConfig(config.id, patch);
+
+    if (config.kind === "sampler") {
+      return <InlineSampler config={config} onUpdate={onUpdate} />;
+    }
+    if (config.kind === "model_provider" || config.kind === "model_config") {
+      return <InlineModel config={config} onUpdate={onUpdate} />;
+    }
+    if (config.kind === "llm") {
+      return <InlineLlm config={config} onUpdate={onUpdate} />;
+    }
+    if (config.kind === "expression") {
+      return <InlineExpression config={config} onUpdate={onUpdate} />;
+    }
   }
 
-  if (config.kind === "sampler") {
-    return (
-      <InlineSampler
-        config={config}
-        onUpdate={(patch) => updateConfig(config.id, patch)}
-      />
-    );
+  if (config?.kind === "sampler" && config.sampler_type === "category") {
+    return <InlineCategoryBadges values={config.values ?? []} />;
   }
 
-  if (config.kind === "model_provider" || config.kind === "model_config") {
-    return (
-      <InlineModel
-        config={config}
-        onUpdate={(patch) => updateConfig(config.id, patch)}
-      />
-    );
-  }
-
-  if (config.kind === "llm") {
-    return (
-      <InlineLlm config={config} onUpdate={(patch) => updateConfig(config.id, patch)} />
-    );
-  }
-
-  if (config.kind === "expression") {
-    return (
-      <InlineExpression
-        config={config}
-        onUpdate={(patch) => updateConfig(config.id, patch)}
-      />
-    );
-  }
-
-  return null;
+  return <p className="text-xs text-muted-foreground">{summary}</p>;
 }
 
 type LlmInputHandleItem = {
@@ -316,8 +302,8 @@ function CanvasNodeBase({
   const semanticInPosition = isTopBottom ? Position.Left : Position.Top;
   const semanticOutPosition = isTopBottom ? Position.Right : Position.Bottom;
 
-  const inlineEditor = renderInlineEditor(config, updateConfig);
   const summary = getConfigSummary(config);
+  const nodeBody = renderNodeBody(config, summary, updateConfig);
   const llmInputHandles = getLlmInputHandleItems(config);
 
   return (
@@ -370,11 +356,7 @@ function CanvasNodeBase({
 
       <BaseNodeContent className="gap-2 px-3 py-2">
         <LlmInputHandles items={llmInputHandles} isTopBottom={isTopBottom} />
-        {inlineEditor ? (
-          inlineEditor
-        ) : (
-          <p className="text-xs text-muted-foreground">{summary}</p>
-        )}
+        {nodeBody}
       </BaseNodeContent>
 
       {showDataHandles && (
diff --git a/studio/frontend/src/features/canvas-lab/components/chip-input.tsx b/studio/frontend/src/features/canvas-lab/components/chip-input.tsx
new file mode 100644
index 0000000000..931e734871
--- /dev/null
+++ b/studio/frontend/src/features/canvas-lab/components/chip-input.tsx
@@ -0,0 +1,67 @@
+import { Button } from "@/components/ui/button";
+import { Cancel01Icon } from "@hugeicons/core-free-icons";
+import { HugeiconsIcon } from "@hugeicons/react";
+import { type KeyboardEvent, type ReactElement, useState } from "react";
+
+type ChipInputProps = {
+  values: string[];
+  onAdd: (value: string) => void;
+  onRemove: (index: number) => void;
+  placeholder?: string;
+};
+
+export function ChipInput({
+  values,
+  onAdd,
+  onRemove,
+  placeholder = "Type and press Enter",
+}: ChipInputProps): ReactElement {
+  const [draft, setDraft] = useState("");
+
+  const handleKeyDown = (event: KeyboardEvent<HTMLInputElement>) => {
+    if (event.key === "Enter") {
+      event.preventDefault();
+      const trimmed = draft.trim();
+      if (trimmed) {
+        onAdd(trimmed);
+        setDraft("");
+      }
+    }
+    if (event.key === "Backspace" && !draft && values.length > 0) {
+      onRemove(values.length - 1);
+    }
+  };
+
+  return (
+    <div className="bg-input/30 border-input focus-within:border-ring focus-within:ring-ring/50 flex min-h-9 flex-wrap items-center gap-1.5 rounded-4xl border bg-clip-padding px-1.5 py-1.5 text-sm transition-colors focus-within:ring-[3px]">
+      {values.map((value, index) => (
+        <span
+          key={`${value}-${index}`}
+          className="bg-muted-foreground/10 text-foreground flex h-[calc(--spacing(5.5))] w-fit items-center justify-center gap-1 rounded-4xl pr-0 pl-2 text-xs font-medium whitespace-nowrap"
+        >
+          {value}
+          <Button
+            type="button"
+            variant="ghost"
+            size="icon-xs"
+            className="-ml-1 opacity-50 hover:opacity-100"
+            onClick={() => onRemove(index)}
+          >
+            <HugeiconsIcon
+              icon={Cancel01Icon}
+              strokeWidth={2}
+              className="pointer-events-none"
+            />
+          </Button>
+        </span>
+      ))}
+      <input
+        className="nodrag min-w-16 flex-1 bg-transparent text-sm outline-none placeholder:text-muted-foreground"
+        placeholder={values.length === 0 ? placeholder : ""}
+        value={draft}
+        onChange={(event) => setDraft(event.target.value)}
+        onKeyDown={handleKeyDown}
+      />
+    </div>
+  );
+}
diff --git a/studio/frontend/src/features/canvas-lab/components/inline/inline-category-badges.tsx b/studio/frontend/src/features/canvas-lab/components/inline/inline-category-badges.tsx
new file mode 100644
index 0000000000..0302c2e7a3
--- /dev/null
+++ b/studio/frontend/src/features/canvas-lab/components/inline/inline-category-badges.tsx
@@ -0,0 +1,88 @@
+import { Badge } from "@/components/ui/badge";
+import { type ReactElement, useLayoutEffect, useRef, useState } from "react";
+
+type InlineCategoryBadgesProps = {
+  values: string[];
+};
+
+export function InlineCategoryBadges({
+  values,
+}: InlineCategoryBadgesProps): ReactElement {
+  const containerRef = useRef<HTMLDivElement>(null);
+  const [visibleCount, setVisibleCount] = useState(values.length);
+
+  useLayoutEffect(() => {
+    const container = containerRef.current;
+    if (!container) return;
+
+    const badges = Array.from(container.children) as HTMLElement[];
+    if (badges.length === 0) {
+      setVisibleCount(0);
+      return;
+    }
+
+    const containerWidth = container.clientWidth;
+    // Reserve space for the "+N" badge (~36px)
+    const overflowBadgeWidth = 36;
+    let count = 0;
+    let usedWidth = 0;
+
+    for (const badge of badges) {
+      const badgeWidth = badge.scrollWidth + 4; // 4px for gap
+      if (usedWidth + badgeWidth > containerWidth - overflowBadgeWidth && count < badges.length - 1) {
+        break;
+      }
+      if (usedWidth + badgeWidth > containerWidth) {
+        break;
+      }
+      usedWidth += badgeWidth;
+      count++;
+    }
+
+    setVisibleCount(count || 1);
+  }, [values]);
+
+  if (values.length === 0) {
+    return <p className="text-xs text-muted-foreground">No values</p>;
+  }
+
+  const overflow = values.length - visibleCount;
+
+  return (
+    <div className="relative">
+      {/* Hidden measurer */}
+      <div
+        ref={containerRef}
+        className="pointer-events-none invisible absolute inset-x-0 top-0 flex flex-nowrap gap-1"
+        aria-hidden
+      >
+        {values.map((v, i) => (
+          <Badge
+            key={`m-${v}-${i}`}
+            variant="secondary"
+            className="corner-squircle h-4 shrink-0 px-1.5 text-[10px]"
+          >
+            {v}
+          </Badge>
+        ))}
+      </div>
+      {/* Visible badges */}
+      <div className="flex flex-wrap gap-1">
+        {values.slice(0, visibleCount).map((v, i) => (
+          <Badge
+            key={`${v}-${i}`}
+            variant="secondary"
+            className="corner-squircle h-4 px-1.5 text-[10px]"
+          >
+            {v}
+          </Badge>
+        ))}
+        {overflow > 0 && (
+          <Badge variant="outline" className="corner-squircle h-4 px-1.5 text-[10px]">
+            +{overflow}
+          </Badge>
+        )}
+      </div>
+    </div>
+  );
+}
diff --git a/studio/frontend/src/features/canvas-lab/components/inline/inline-llm.tsx b/studio/frontend/src/features/canvas-lab/components/inline/inline-llm.tsx
index f1195ea628..d9241dfb08 100644
--- a/studio/frontend/src/features/canvas-lab/components/inline/inline-llm.tsx
+++ b/studio/frontend/src/features/canvas-lab/components/inline/inline-llm.tsx
@@ -1,4 +1,11 @@
-import { Input } from "@/components/ui/input";
+import {
+  Combobox,
+  ComboboxContent,
+  ComboboxEmpty,
+  ComboboxInput,
+  ComboboxItem,
+  ComboboxList,
+} from "@/components/ui/combobox";
 import {
   Select,
   SelectContent,
@@ -6,7 +13,8 @@ import {
   SelectTrigger,
   SelectValue,
 } from "@/components/ui/select";
-import type { ReactElement } from "react";
+import { type ReactElement, useEffect, useMemo, useRef, useState } from "react";
+import { useCanvasLabStore } from "../../stores/canvas-lab";
 import type { LlmConfig } from "../../types";
 import { InlineField } from "./inline-field";
 
@@ -36,21 +44,64 @@ const CODE_LANG_OPTIONS = [
 
 export function InlineLlm({ config, onUpdate }: InlineLlmProps): ReactElement {
   const isCode = config.llm_type === "code";
+  const configs = useCanvasLabStore((state) => state.configs);
+  const modelConfigAliases = useMemo(
+    () =>
+      Object.values(configs)
+        .filter((c) => c.kind === "model_config")
+        .map((c) => c.name),
+    [configs],
+  );
+  const [aliasInput, setAliasInput] = useState(config.model_alias);
+  const anchorRef = useRef<HTMLDivElement>(null);
+
+  useEffect(() => {
+    setAliasInput(config.model_alias);
+  }, [config.model_alias]);
 
   return (
     <div className="space-y-3">
       <InlineField label="Model alias">
-        <Input
-          className="nodrag h-8 w-full text-xs"
-          placeholder="Model alias"
-          value={config.model_alias}
-          onChange={(event) =>
-            onUpdate({
-              // biome-ignore lint/style/useNamingConvention: api schema
-              model_alias: event.target.value,
-            })
-          }
-        />
+        <div ref={anchorRef}>
+          <Combobox
+            items={modelConfigAliases}
+            filteredItems={modelConfigAliases}
+            filter={null}
+            value={config.model_alias || null}
+            onValueChange={(value) =>
+              onUpdate({
+                // biome-ignore lint/style/useNamingConvention: api schema
+                model_alias: value ?? "",
+              })
+            }
+            onInputValueChange={setAliasInput}
+            itemToStringValue={(value) => value}
+            autoHighlight={true}
+          >
+            <ComboboxInput
+              className="nodrag h-8 w-full text-xs"
+              placeholder="Model alias"
+              onBlur={() => {
+                if (aliasInput !== config.model_alias) {
+                  onUpdate({
+                    // biome-ignore lint/style/useNamingConvention: api schema
+                    model_alias: aliasInput,
+                  });
+                }
+              }}
+            />
+            <ComboboxContent anchor={anchorRef}>
+              <ComboboxEmpty>No model configs found</ComboboxEmpty>
+              <ComboboxList>
+                {(alias: string) => (
+                  <ComboboxItem key={alias} value={alias}>
+                    {alias}
+                  </ComboboxItem>
+                )}
+              </ComboboxList>
+            </ComboboxContent>
+          </Combobox>
+        </div>
       </InlineField>
       {isCode && (
         <InlineField label="Code language">
@@ -77,7 +128,7 @@ export function InlineLlm({ config, onUpdate }: InlineLlmProps): ReactElement {
         </InlineField>
       )}
       <p className="text-[11px] text-muted-foreground">
-        Prompt/System are edited in dialog or linked input nodes.
+        Prompt/system edited on aux nodes.
       </p>
     </div>
   );
diff --git a/studio/frontend/src/features/canvas-lab/dialogs/config-dialog.tsx b/studio/frontend/src/features/canvas-lab/dialogs/config-dialog.tsx
index acce6affe7..43a58ceaa3 100644
--- a/studio/frontend/src/features/canvas-lab/dialogs/config-dialog.tsx
+++ b/studio/frontend/src/features/canvas-lab/dialogs/config-dialog.tsx
@@ -37,7 +37,7 @@ export function ConfigDialog({
         position="absolute"
         overlayPosition="absolute"
         overlayClassName="bg-transparent"
-        className="sm:max-w-2xl shadow-border"
+        className="corner-squircle max-h-[650px] overflow-auto sm:max-w-2xl shadow-border"
       >
         <DialogShell />
         {!config && (
@@ -51,7 +51,7 @@ export function ConfigDialog({
             {(config.kind === "sampler" ||
               config.kind === "llm" ||
               config.kind === "expression") && (
-              <div className="flex items-center justify-between gap-3 rounded-2xl border border-border/60 px-3 py-2">
+              <div className="flex items-center corner-squircle justify-between gap-3 rounded-2xl border border-border/60 px-3 py-2">
                 <div>
                   <p className="text-sm font-semibold">Drop from final dataset</p>
                   <p className="text-xs text-muted-foreground">
diff --git a/studio/frontend/src/features/canvas-lab/dialogs/expression/expression-dialog.tsx b/studio/frontend/src/features/canvas-lab/dialogs/expression/expression-dialog.tsx
index 55756a3cc4..44cb4d8d04 100644
--- a/studio/frontend/src/features/canvas-lab/dialogs/expression/expression-dialog.tsx
+++ b/studio/frontend/src/features/canvas-lab/dialogs/expression/expression-dialog.tsx
@@ -69,7 +69,7 @@ export function ExpressionDialog({
         </label>
         <Textarea
           id={exprId}
-          className="nodrag"
+          className="corner-squircle nodrag"
           placeholder="{{ category_1 }} - {{ subcategory_1 }}"
           value={config.expr}
           onChange={(event) => updateField("expr", event.target.value)}
diff --git a/studio/frontend/src/features/canvas-lab/dialogs/import-dialog.tsx b/studio/frontend/src/features/canvas-lab/dialogs/import-dialog.tsx
index 83badb8a98..bf79f8adce 100644
--- a/studio/frontend/src/features/canvas-lab/dialogs/import-dialog.tsx
+++ b/studio/frontend/src/features/canvas-lab/dialogs/import-dialog.tsx
@@ -49,7 +49,7 @@ export function ImportDialog({
         position="absolute"
         overlayPosition="absolute"
         overlayClassName="bg-transparent"
-        className="max-h-[85vh] overflow-auto sm:max-w-2xl"
+        className="corner-squircle max-h-[650px] overflow-auto sm:max-w-2xl"
       >
         <DialogHeader>
           <DialogTitle>Import recipe</DialogTitle>
@@ -63,7 +63,7 @@ export function ImportDialog({
           </label>
           <Textarea
             id={payloadId}
-            className="nodrag min-h-[220px]"
+            className="corner-squircle nodrag min-h-[220px]"
             placeholder='{"recipe": { "columns": [] }}'
             value={value}
             onChange={(event) => setValue(event.target.value)}
diff --git a/studio/frontend/src/features/canvas-lab/dialogs/llm/available-variables.tsx b/studio/frontend/src/features/canvas-lab/dialogs/llm/available-variables.tsx
new file mode 100644
index 0000000000..70cde57328
--- /dev/null
+++ b/studio/frontend/src/features/canvas-lab/dialogs/llm/available-variables.tsx
@@ -0,0 +1,36 @@
+import { Badge } from "@/components/ui/badge";
+import type { ReactElement } from "react";
+import { useCanvasLabStore } from "../../stores/canvas-lab";
+import { getAvailableVariables } from "../../utils/variables";
+
+type AvailableVariablesProps = {
+  configId: string;
+};
+
+export function AvailableVariables({
+  configId,
+}: AvailableVariablesProps): ReactElement | null {
+  const configs = useCanvasLabStore((state) => state.configs);
+  const vars = getAvailableVariables(configs, configId);
+
+  if (vars.length === 0) return null;
+
+  return (
+    <div className="corner-squircle rounded-2xl border border-border/60 px-3 py-2">
+      <p className="mb-2 text-xs font-semibold uppercase text-muted-foreground">
+        Available variables
+      </p>
+      <div className="flex flex-wrap gap-1.5">
+        {vars.map((v) => (
+          <Badge
+            key={v}
+            variant="secondary"
+            className="corner-squircle font-mono text-[11px]"
+          >
+            {`{{ ${v} }}`}
+          </Badge>
+        ))}
+      </div>
+    </div>
+  );
+}
diff --git a/studio/frontend/src/features/canvas-lab/dialogs/llm/llm-dialog.tsx b/studio/frontend/src/features/canvas-lab/dialogs/llm/llm-dialog.tsx
index 34840b87a2..9320af9f1b 100644
--- a/studio/frontend/src/features/canvas-lab/dialogs/llm/llm-dialog.tsx
+++ b/studio/frontend/src/features/canvas-lab/dialogs/llm/llm-dialog.tsx
@@ -15,8 +15,9 @@ import {
   SelectValue,
 } from "@/components/ui/select";
 import { Textarea } from "@/components/ui/textarea";
-import { type ReactElement, useRef } from "react";
+import { type ReactElement, useEffect, useRef, useState } from "react";
 import type { LlmConfig, Score } from "../../types";
+import { AvailableVariables } from "./available-variables";
 import { NameField } from "../shared/name-field";
 
 const CODE_LANG_OPTIONS = [
@@ -55,6 +56,10 @@ export function LlmDialog({
   const outputFormatId = `${config.id}-output-format`;
   const systemPromptId = `${config.id}-system-prompt`;
   const modelAliasAnchorRef = useRef<HTMLDivElement>(null);
+  const [aliasInput, setAliasInput] = useState(config.model_alias);
+  useEffect(() => {
+    setAliasInput(config.model_alias);
+  }, [config.model_alias]);
   const scores = config.scores ?? [];
   const updateField = <K extends keyof LlmConfig>(
     key: K,
@@ -81,6 +86,7 @@ export function LlmDialog({
   };
   return (
     <div className="space-y-4">
+      <AvailableVariables configId={config.id} />
       <NameField
         value={config.name}
         onChange={(value) => onUpdate({ name: value })}
@@ -99,7 +105,7 @@ export function LlmDialog({
             filter={null}
             value={config.model_alias || null}
             onValueChange={(value) => updateField("model_alias", value ?? "")}
-            onInputValueChange={(value) => updateField("model_alias", value)}
+            onInputValueChange={setAliasInput}
             itemToStringValue={(value) => value}
             autoHighlight={true}
           >
@@ -107,6 +113,11 @@ export function LlmDialog({
               id={modelAliasId}
               className="nodrag w-full"
               placeholder="Pick model alias or type"
+              onBlur={() => {
+                if (aliasInput !== config.model_alias) {
+                  updateField("model_alias", aliasInput);
+                }
+              }}
             />
             <ComboboxContent anchor={modelAliasAnchorRef}>
               <ComboboxEmpty>No model configs found</ComboboxEmpty>
@@ -158,7 +169,7 @@ export function LlmDialog({
         </label>
         <Textarea
           id={promptId}
-          className="nodrag"
+          className="corner-squircle nodrag"
           value={config.prompt}
           onChange={(event) => updateField("prompt", event.target.value)}
         />
@@ -179,7 +190,7 @@ export function LlmDialog({
             </p>
           )}
           {scores.map((score, index) => (
-            <div key={`${config.id}-score-${index}`} className="flex items-center justify-between rounded-xl border border-border/60 px-3 py-2">
+            <div key={`${config.id}-score-${index}`} className="flex items-center justify-between rounded-xl corner-squircle border border-border/60 px-3 py-2">
               <div>
                 <p className="text-xs font-semibold text-foreground">
                   {score.name.trim() || `Scorer ${index + 1}`}
@@ -205,7 +216,7 @@ export function LlmDialog({
           </label>
           <Textarea
             id={outputFormatId}
-            className="nodrag"
+            className="corner-squircle nodrag"
             value={config.output_format ?? ""}
             onChange={(event) =>
               updateField("output_format", event.target.value)
@@ -225,7 +236,7 @@ export function LlmDialog({
         </label>
         <Textarea
           id={systemPromptId}
-          className="nodrag"
+          className="corner-squircle nodrag"
           value={config.system_prompt}
           onChange={(event) => updateField("system_prompt", event.target.value)}
         />
diff --git a/studio/frontend/src/features/canvas-lab/dialogs/models/model-config-dialog.tsx b/studio/frontend/src/features/canvas-lab/dialogs/models/model-config-dialog.tsx
index dad4063b2a..c040954d05 100644
--- a/studio/frontend/src/features/canvas-lab/dialogs/models/model-config-dialog.tsx
+++ b/studio/frontend/src/features/canvas-lab/dialogs/models/model-config-dialog.tsx
@@ -8,7 +8,7 @@ import {
   ComboboxList,
 } from "@/components/ui/combobox";
 import { Input } from "@/components/ui/input";
-import { type ReactElement, useRef } from "react";
+import { type ReactElement, useEffect, useRef, useState } from "react";
 import type { ModelConfig } from "../../types";
 import { NameField } from "../shared/name-field";
 
@@ -29,6 +29,10 @@ export function ModelConfigDialog({
   const topPId = `${config.id}-top-p`;
   const maxTokensId = `${config.id}-max-tokens`;
   const providerAnchorRef = useRef<HTMLDivElement>(null);
+  const [providerInput, setProviderInput] = useState(config.provider);
+  useEffect(() => {
+    setProviderInput(config.provider);
+  }, [config.provider]);
   const updateField = <K extends keyof ModelConfig>(
     key: K,
     value: ModelConfig[K],
@@ -71,7 +75,7 @@ export function ModelConfigDialog({
             filter={null}
             value={config.provider || null}
             onValueChange={(value) => updateField("provider", value ?? "")}
-            onInputValueChange={(value) => updateField("provider", value)}
+            onInputValueChange={setProviderInput}
             itemToStringValue={(value) => value}
             autoHighlight={true}
           >
@@ -79,6 +83,11 @@ export function ModelConfigDialog({
               id={providerId}
               className="nodrag w-full"
               placeholder="Pick provider or type name"
+              onBlur={() => {
+                if (providerInput !== config.provider) {
+                  updateField("provider", providerInput);
+                }
+              }}
             />
             <ComboboxContent anchor={providerAnchorRef}>
               <ComboboxEmpty>No providers found</ComboboxEmpty>
diff --git a/studio/frontend/src/features/canvas-lab/dialogs/models/model-provider-dialog.tsx b/studio/frontend/src/features/canvas-lab/dialogs/models/model-provider-dialog.tsx
index 182184fd25..cdd04a0855 100644
--- a/studio/frontend/src/features/canvas-lab/dialogs/models/model-provider-dialog.tsx
+++ b/studio/frontend/src/features/canvas-lab/dialogs/models/model-provider-dialog.tsx
@@ -102,7 +102,7 @@ export function ModelProviderDialog({
         </label>
         <Textarea
           id={extraHeadersId}
-          className="nodrag"
+          className="corner-squircle nodrag"
           placeholder='{"X-Header": "value"}'
           value={config.extra_headers ?? ""}
           onChange={(event) =>
@@ -119,7 +119,7 @@ export function ModelProviderDialog({
         </label>
         <Textarea
           id={extraBodyId}
-          className="nodrag"
+          className="corner-squircle nodrag"
           placeholder='{"key": "value"}'
           value={config.extra_body ?? ""}
           onChange={(event) => updateField("extra_body", event.target.value)}
diff --git a/studio/frontend/src/features/canvas-lab/dialogs/processors-dialog.tsx b/studio/frontend/src/features/canvas-lab/dialogs/processors-dialog.tsx
index 9dd0a771af..e4416fe6ad 100644
--- a/studio/frontend/src/features/canvas-lab/dialogs/processors-dialog.tsx
+++ b/studio/frontend/src/features/canvas-lab/dialogs/processors-dialog.tsx
@@ -1,8 +1,9 @@
 import { Button } from "@/components/ui/button";
-import { Dialog, DialogContent, DialogFooter } from "@/components/ui/dialog";
+import { Dialog, DialogContent, DialogFooter, DialogTitle } from "@/components/ui/dialog";
 import { Input } from "@/components/ui/input";
 import { Switch } from "@/components/ui/switch";
 import { Textarea } from "@/components/ui/textarea";
+import { VisuallyHidden } from "radix-ui";
 import { type ReactElement, useMemo } from "react";
 import type { CanvasProcessorConfig } from "../types";
 import { buildDefaultSchemaTransform } from "../utils/processors";
@@ -65,8 +66,11 @@ export function ProcessorsDialog({
         position="absolute"
         overlayPosition="absolute"
         overlayClassName="bg-transparent"
-        className="max-h-[85vh] overflow-auto sm:max-w-2xl"
+        className="corner-squircle max-h-[650px] overflow-auto sm:max-w-2xl"
       >
+        <VisuallyHidden.Root>
+          <DialogTitle>Processors</DialogTitle>
+        </VisuallyHidden.Root>
         <div className="space-y-4">
           <div className="flex items-center justify-between gap-3 rounded-2xl border border-border/60 px-3 py-2">
             <div>
@@ -106,7 +110,7 @@ export function ProcessorsDialog({
                 </label>
                 <Textarea
                   id={templateId}
-                  className="nodrag min-h-[220px]"
+                  className="corner-squircle nodrag min-h-[220px]"
                   value={schemaProcessor.template}
                   onChange={(event) =>
                     updateSchema({ template: event.target.value })
diff --git a/studio/frontend/src/features/canvas-lab/dialogs/samplers/category-dialog.tsx b/studio/frontend/src/features/canvas-lab/dialogs/samplers/category-dialog.tsx
index 8276449422..e9daedfc64 100644
--- a/studio/frontend/src/features/canvas-lab/dialogs/samplers/category-dialog.tsx
+++ b/studio/frontend/src/features/canvas-lab/dialogs/samplers/category-dialog.tsx
@@ -1,8 +1,8 @@
-import { Badge } from "@/components/ui/badge";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
 import { type ReactElement, useState } from "react";
 import type { SamplerConfig } from "../../types";
+import { ChipInput } from "../../components/chip-input";
 import { NameField } from "../shared/name-field";
 
 type CategoryDialogProps = {
@@ -14,29 +14,11 @@ export function CategoryDialog({
   config,
   onUpdate,
 }: CategoryDialogProps): ReactElement {
-  const [valueDraft, setValueDraft] = useState("");
   const [conditionDraft, setConditionDraft] = useState("");
-  const [conditionalValueDrafts, setConditionalValueDrafts] = useState<
-    Record<string, string>
-  >({});
-  const valuesInputId = `${config.id}-values`;
   const conditionInputId = `${config.id}-conditional-rule`;
 
   const conditional = config.conditional_params ?? {};
 
-  const handleAddValue = () => {
-    const nextValue = valueDraft.trim();
-    if (!nextValue) {
-      return;
-    }
-    const values = config.values ? [...config.values] : [];
-    const weights = config.weights ? [...config.weights] : [];
-    values.push(nextValue);
-    weights.push(null);
-    onUpdate({ values, weights });
-    setValueDraft("");
-  };
-
   const handleAddCondition = () => {
     const condition = conditionDraft.trim();
     if (!condition || conditional[condition]) {
@@ -66,29 +48,6 @@ export function CategoryDialog({
     });
   };
 
-  const addConditionalValue = (condition: string) => {
-    const draft = conditionalValueDrafts[condition]?.trim();
-    if (!draft) {
-      return;
-    }
-    const current = conditional[condition] ?? {
-      // biome-ignore lint/style/useNamingConvention: api schema
-      sampler_type: "category" as const,
-      values: [],
-      weights: [],
-    };
-    const values = [...(current.values ?? []), draft];
-    const weights = [...(current.weights ?? []), null];
-    onUpdate({
-      // biome-ignore lint/style/useNamingConvention: api schema
-      conditional_params: {
-        ...conditional,
-        [condition]: { ...current, values, weights },
-      },
-    });
-    setConditionalValueDrafts((prev) => ({ ...prev, [condition]: "" }));
-  };
-
   return (
     <div className="space-y-4">
       <NameField
@@ -97,50 +56,25 @@ export function CategoryDialog({
       />
       <div className="space-y-3">
         <div className="grid gap-2">
-          <label
-            className="text-xs font-semibold uppercase text-muted-foreground"
-            htmlFor={valuesInputId}
-          >
+          <p className="text-xs font-semibold uppercase text-muted-foreground">
             Values
-          </label>
-          <div className="flex gap-2">
-            <Input
-              id={valuesInputId}
-              className="nodrag"
-              placeholder="Add a value"
-              value={valueDraft}
-              onChange={(event) => setValueDraft(event.target.value)}
-              onKeyDown={(event) => {
-                if (event.key === "Enter") {
-                  event.preventDefault();
-                  handleAddValue();
-                }
-              }}
-            />
-            <Button type="button" size="sm" onClick={handleAddValue}>
-              Add
-            </Button>
-          </div>
-          <div className="flex flex-wrap gap-2">
-            {(config.values ?? []).map((value, index) => (
-              <Badge key={value} variant="secondary">
-                <span>{value}</span>
-                <button
-                  type="button"
-                  className="ml-2 text-xs"
-                  onClick={() => {
-                    const values = [...(config.values ?? [])];
-                    const weights = [...(config.weights ?? [])];
-                    values.splice(index, 1);
-                    weights.splice(index, 1);
-                    onUpdate({ values, weights });
-                  }}
-                >
-                  ×
-                </button>
-              </Badge>
-            ))}
-          </div>
+          </p>
+          <ChipInput
+            values={config.values ?? []}
+            onAdd={(value) => {
+              const values = [...(config.values ?? []), value];
+              const weights = [...(config.weights ?? []), null];
+              onUpdate({ values, weights });
+            }}
+            onRemove={(index) => {
+              const values = [...(config.values ?? [])];
+              const weights = [...(config.weights ?? [])];
+              values.splice(index, 1);
+              weights.splice(index, 1);
+              onUpdate({ values, weights });
+            }}
+            placeholder="Type a value and press Enter"
+          />
         </div>
         <div className="grid gap-2">
           <p className="text-xs font-semibold uppercase text-muted-foreground">
@@ -149,12 +83,12 @@ export function CategoryDialog({
           <div className="grid gap-2">
             {(config.values ?? []).map((value, index) => (
               <div key={`${value}-weight`} className="flex items-center gap-3">
-                <span className="text-xs text-muted-foreground w-20 truncate">
+                <span className="text-xs text-muted-foreground max-w-20 truncate">
                   {value}
                 </span>
                 <Input
                   type="number"
-                  className="nodrag"
+                  className="nodrag w-full"
                   placeholder="Weight"
                   value={config.weights?.[index] ?? ""}
                   onChange={(event) => {
@@ -213,61 +147,34 @@ export function CategoryDialog({
                 Remove
               </Button>
             </div>
-            <div className="flex gap-2">
-              <Input
-                className="nodrag"
-                placeholder="Add conditional value"
-                value={conditionalValueDrafts[condition] ?? ""}
-                onChange={(event) =>
-                  setConditionalValueDrafts((prev) => ({
-                    ...prev,
-                    [condition]: event.target.value,
-                  }))
-                }
-                onKeyDown={(event) => {
-                  if (event.key === "Enter") {
-                    event.preventDefault();
-                    addConditionalValue(condition);
-                  }
-                }}
-              />
-              <Button
-                type="button"
-                size="sm"
-                onClick={() => addConditionalValue(condition)}
-              >
-                Add
-              </Button>
-            </div>
-            <div className="flex flex-wrap gap-2">
-              {(params.values ?? []).map((value, index) => (
-                <Badge
-                  key={`${condition}-${value}-${index}`}
-                  variant="secondary"
-                >
-                  <span>{value}</span>
-                  <button
-                    type="button"
-                    className="ml-2 text-xs"
-                    onClick={() => {
-                      const values = [...(params.values ?? [])];
-                      const weights = [...(params.weights ?? [])];
-                      values.splice(index, 1);
-                      weights.splice(index, 1);
-                      onUpdate({
-                        // biome-ignore lint/style/useNamingConvention: api schema
-                        conditional_params: {
-                          ...conditional,
-                          [condition]: { ...params, values, weights },
-                        },
-                      });
-                    }}
-                  >
-                    ×
-                  </button>
-                </Badge>
-              ))}
-            </div>
+            <ChipInput
+              values={params.values ?? []}
+              onAdd={(value) => {
+                const values = [...(params.values ?? []), value];
+                const weights = [...(params.weights ?? []), null];
+                onUpdate({
+                  // biome-ignore lint/style/useNamingConvention: api schema
+                  conditional_params: {
+                    ...conditional,
+                    [condition]: { ...params, values, weights },
+                  },
+                });
+              }}
+              onRemove={(index) => {
+                const values = [...(params.values ?? [])];
+                const weights = [...(params.weights ?? [])];
+                values.splice(index, 1);
+                weights.splice(index, 1);
+                onUpdate({
+                  // biome-ignore lint/style/useNamingConvention: api schema
+                  conditional_params: {
+                    ...conditional,
+                    [condition]: { ...params, values, weights },
+                  },
+                });
+              }}
+              placeholder="Type a conditional value and press Enter"
+            />
             <div className="grid gap-2">
               <p className="text-xs font-semibold uppercase text-muted-foreground">
                 Rule weights (optional)
diff --git a/studio/frontend/src/features/canvas-lab/dialogs/samplers/subcategory-dialog.tsx b/studio/frontend/src/features/canvas-lab/dialogs/samplers/subcategory-dialog.tsx
index 46ff926d9d..2a444fc1a7 100644
--- a/studio/frontend/src/features/canvas-lab/dialogs/samplers/subcategory-dialog.tsx
+++ b/studio/frontend/src/features/canvas-lab/dialogs/samplers/subcategory-dialog.tsx
@@ -1,6 +1,3 @@
-import { Badge } from "@/components/ui/badge";
-import { Button } from "@/components/ui/button";
-import { Input } from "@/components/ui/input";
 import {
   Select,
   SelectContent,
@@ -8,14 +5,9 @@ import {
   SelectTrigger,
   SelectValue,
 } from "@/components/ui/select";
-import {
-  type ReactElement,
-  useCallback,
-  useEffect,
-  useMemo,
-  useState,
-} from "react";
+import { type ReactElement, useCallback, useEffect, useMemo } from "react";
 import type { SamplerConfig } from "../../types";
+import { ChipInput } from "../../components/chip-input";
 import { NameField } from "../shared/name-field";
 
 type SubcategoryDialogProps = {
@@ -29,7 +21,6 @@ export function SubcategoryDialog({
   categoryOptions,
   onUpdate,
 }: SubcategoryDialogProps): ReactElement {
-  const [drafts, setDrafts] = useState<Record<string, string>>({});
   const parentSelectId = `${config.id}-parent-category`;
   const updateField = useCallback(
     <K extends keyof SamplerConfig>(key: K, value: SamplerConfig[K]) => {
@@ -72,19 +63,6 @@ export function SubcategoryDialog({
     }
   }, [ensureMapping, parent]);
 
-  const addSubValue = (categoryValue: string) => {
-    const draft = drafts[categoryValue]?.trim();
-    if (!draft) {
-      return;
-    }
-    const next = { ...mapping };
-    const list = next[categoryValue] ? [...next[categoryValue]] : [];
-    list.push(draft);
-    next[categoryValue] = list;
-    updateField("subcategory_mapping", next);
-    setDrafts((prev) => ({ ...prev, [categoryValue]: "" }));
-  };
-
   return (
     <div className="space-y-4">
       <NameField
@@ -119,15 +97,15 @@ export function SubcategoryDialog({
               ))}
             </SelectContent>
           </Select>
+          <p className="text-xs text-muted-foreground">
+            Map each parent category value to its subcategory options below.
+          </p>
         </div>
         {categoryValues.length > 0 && (
           <div className="grid gap-4">
             {categoryValues.map((value) => (
-              <div
-                key={value}
-                className="rounded-2xl border border-border/60 p-3"
-              >
-                <div className="flex items-center justify-between gap-2">
+              <div key={value}>
+                <div className="mb-2 flex items-center justify-between gap-2">
                   <p className="text-sm font-semibold text-foreground">
                     {value}
                   </p>
@@ -135,52 +113,24 @@ export function SubcategoryDialog({
                     {mapping[value]?.length ?? 0} subvalues
                   </span>
                 </div>
-                <div className="mt-3 flex gap-2">
-                  <Input
-                    className="nodrag"
-                    placeholder="Add subcategory"
-                    value={drafts[value] ?? ""}
-                    onChange={(event) =>
-                      setDrafts((prev) => ({
-                        ...prev,
-                        [value]: event.target.value,
-                      }))
-                    }
-                    onKeyDown={(event) => {
-                      if (event.key === "Enter") {
-                        event.preventDefault();
-                        addSubValue(value);
-                      }
-                    }}
-                  />
-                  <Button
-                    type="button"
-                    size="sm"
-                    onClick={() => addSubValue(value)}
-                  >
-                    Add
-                  </Button>
-                </div>
-                <div className="mt-2 flex flex-wrap gap-2">
-                  {(mapping[value] ?? []).map((item, index) => (
-                    <Badge key={`${value}-${item}`} variant="secondary">
-                      <span>{item}</span>
-                      <button
-                        type="button"
-                        className="ml-2 text-xs"
-                        onClick={() => {
-                          const next = { ...mapping };
-                          const list = [...(next[value] ?? [])];
-                          list.splice(index, 1);
-                          next[value] = list;
-                          updateField("subcategory_mapping", next);
-                        }}
-                      >
-                        ×
-                      </button>
-                    </Badge>
-                  ))}
-                </div>
+                <ChipInput
+                  values={mapping[value] ?? []}
+                  onAdd={(item) => {
+                    const next = { ...mapping };
+                    const list = next[value] ? [...next[value]] : [];
+                    list.push(item);
+                    next[value] = list;
+                    updateField("subcategory_mapping", next);
+                  }}
+                  onRemove={(index) => {
+                    const next = { ...mapping };
+                    const list = [...(next[value] ?? [])];
+                    list.splice(index, 1);
+                    next[value] = list;
+                    updateField("subcategory_mapping", next);
+                  }}
+                  placeholder="Type subcategory and press Enter"
+                />
                 {(mapping[value] ?? []).length === 0 && (
                   <p className="mt-2 text-xs text-rose-500">
                     Add at least 1 subcategory.
diff --git a/studio/frontend/src/features/canvas-lab/dialogs/shared/validation-banner.tsx b/studio/frontend/src/features/canvas-lab/dialogs/shared/validation-banner.tsx
index 5979607518..088ebfd36c 100644
--- a/studio/frontend/src/features/canvas-lab/dialogs/shared/validation-banner.tsx
+++ b/studio/frontend/src/features/canvas-lab/dialogs/shared/validation-banner.tsx
@@ -12,13 +12,9 @@ export function ValidationBanner({
     return null;
   }
   return (
-    <div className="rounded-2xl border border-amber-200 bg-amber-50 px-4 py-3 text-xs text-amber-800">
-      <p className="font-semibold">Fix before run</p>
-      <ul className="mt-1 list-disc pl-4">
-        {errors.map((item) => (
-          <li key={item}>{item}</li>
-        ))}
-      </ul>
-    </div>
+    <p className="text-xs text-amber-600">
+      <span className="font-semibold">Fix before run: </span>
+      {errors.join(". ")}.
+    </p>
   );
 }
diff --git a/studio/frontend/src/features/canvas-lab/utils/variables.ts b/studio/frontend/src/features/canvas-lab/utils/variables.ts
new file mode 100644
index 0000000000..2cf1b1df5c
--- /dev/null
+++ b/studio/frontend/src/features/canvas-lab/utils/variables.ts
@@ -0,0 +1,26 @@
+import type { NodeConfig } from "../types";
+
+export function getAvailableVariables(
+  configs: Record<string, NodeConfig>,
+  currentId: string,
+): string[] {
+  const vars: string[] = [];
+  for (const config of Object.values(configs)) {
+    if (config.id === currentId) continue;
+    if (config.kind === "model_provider" || config.kind === "model_config") continue;
+    vars.push(config.name);
+    if (config.kind === "llm" && config.llm_type === "structured" && config.output_format) {
+      try {
+        const schema = JSON.parse(config.output_format);
+        if (schema.properties) {
+          for (const key of Object.keys(schema.properties)) {
+            vars.push(`${config.name}.${key}`);
+          }
+        }
+      } catch {
+        /* skip invalid JSON */
+      }
+    }
+  }
+  return vars;
+}