diff --git a/frontend/src/lib/components/ScriptEditor.svelte b/frontend/src/lib/components/ScriptEditor.svelte
index fe13e265b3..81214a09dd 100644
--- a/frontend/src/lib/components/ScriptEditor.svelte
+++ b/frontend/src/lib/components/ScriptEditor.svelte
@@ -679,7 +679,15 @@
 		args = nargs
 	}
 
-	export async function runTest() {
+	export async function runTest(opts?: { cascade?: boolean }) {
+		// When the caller forces a cascade choice (e.g. the canvas runnable
+		// menu's "Run + trigger N downstream"), also flip the persistent
+		// `cascadeDownstream` state so the split button's label/icon reflect
+		// the active mode after the run kicks off — keeps "what mode am I in"
+		// visible instead of having a one-off run silently disagree with the
+		// UI. The caller is welcome to bump the signal repeatedly; we just
+		// keep the latest choice as the active mode.
+		if (opts?.cascade !== undefined) cascadeDownstream = opts.cascade
 		// Discard any previous recording when running a normal test
 		if (!scriptRecording.active) {
 			lastRecording = undefined
@@ -1717,9 +1725,13 @@
 											contentClasses="p-0"
 										>
 											{#snippet trigger()}
+												<!-- min-h-7 matches Button's unifiedSize="sm" (28px) so
+												     the caret stretches to the same height as the
+												     primary Test button. self-stretch falls back if the
+												     parent's items-stretch is overridden upstream. -->
 												<button
 													type="button"
-													class="px-1.5 flex items-center justify-center bg-blue-100 dark:bg-blue-900/30 hover:bg-blue-200 dark:hover:bg-blue-900/60 text-primary border-l border-blue-300 dark:border-blue-700 transition-colors"
+													class="self-stretch min-h-7 px-1.5 flex items-center justify-center bg-blue-100 dark:bg-blue-900/30 hover:bg-blue-200 dark:hover:bg-blue-900/60 text-primary border-l border-blue-300 dark:border-blue-700 transition-colors"
 													title="Run options"
 													aria-label="Run options"
 												>
diff --git a/frontend/src/lib/components/assets/AssetGraph/AssetGraphCanvas.svelte b/frontend/src/lib/components/assets/AssetGraph/AssetGraphCanvas.svelte
index 8eb04e633f..9cf36f4123 100644
--- a/frontend/src/lib/components/assets/AssetGraph/AssetGraphCanvas.svelte
+++ b/frontend/src/lib/components/assets/AssetGraph/AssetGraphCanvas.svelte
@@ -74,6 +74,11 @@
 			kind: 'script' | 'flow'
 			path: string
 			unsaved?: boolean
+			// Whether to let the asset-trigger cascade fan out to downstream
+			// subscribers after this run succeeds. Undefined = use the caller's
+			// default (no skip arg injected); true = explicit cascade; false =
+			// inject `_wmill_skip_asset_dispatch: true` to suppress.
+			cascade?: boolean
 		}) => Promise<string | undefined>
 		// Page-supplied dispatch for the per-runnable-node action menu.
 		// Drafts are discarded immediately by the page; persisted scripts
@@ -172,6 +177,34 @@
 			producersByAsset.set(key, list)
 		}
 
+		// Downstream subscriber count per producer script. Counts distinct
+		// script subscribers (excluding self and flow subs, mirroring the V1
+		// dispatch policy) across all assets the script writes. Drives the
+		// "Run + trigger N downstream" menu item on RunnableNode and lets the
+		// pipeline page short-circuit cascade UX when there's nothing to fan
+		// out to.
+		const subscribersByAsset = new Map<string, Set<string>>()
+		for (const t of g.triggers ?? []) {
+			if (t.trigger_kind !== 'asset' || t.runnable_kind !== 'script') continue
+			const key = `${t.asset_kind}:${t.asset_path}`
+			const set = subscribersByAsset.get(key) ?? new Set<string>()
+			set.add(t.runnable_path)
+			subscribersByAsset.set(key, set)
+		}
+		const downstreamSetsByScript = new Map<string, Set<string>>()
+		for (const e of g.edges ?? []) {
+			if (e.runnable_kind !== 'script') continue
+			const access = e.access_type ?? 'r'
+			if (access !== 'w' && access !== 'rw') continue
+			const subs = subscribersByAsset.get(`${e.asset_kind}:${e.asset_path}`)
+			if (!subs) continue
+			const merged = downstreamSetsByScript.get(e.runnable_path) ?? new Set<string>()
+			for (const s of subs) if (s !== e.runnable_path) merged.add(s)
+			downstreamSetsByScript.set(e.runnable_path, merged)
+		}
+		const downstreamByScript = new Map<string, number>()
+		for (const [path, set] of downstreamSetsByScript) downstreamByScript.set(path, set.size)
+
 		for (const a of g.assets) {
 			const assetId = `asset:${a.kind}:${a.path}`
 			nodes.push({
@@ -206,13 +239,15 @@
 					// click → run with no extra UI clutter.
 					onRunSelf:
 						r.usage_kind === 'script' && onRunProducer
-							? () =>
+							? (opts?: { cascade?: boolean }) =>
 									onRunProducer({
 										kind: 'script',
 										path: r.path,
-										unsaved: r.unsaved ?? false
+										unsaved: r.unsaved ?? false,
+										cascade: opts?.cascade
 									})
 							: undefined,
+					downstreamCount: downstreamByScript.get(r.path) ?? 0,
 					onSelectSelf: () =>
 						onselect?.({
 							kind: 'runnable',
diff --git a/frontend/src/lib/components/assets/AssetGraph/AssetGraphDetailsPane.svelte b/frontend/src/lib/components/assets/AssetGraph/AssetGraphDetailsPane.svelte
index fdc3420254..b84e34215c 100644
--- a/frontend/src/lib/components/assets/AssetGraph/AssetGraphDetailsPane.svelte
+++ b/frontend/src/lib/components/assets/AssetGraph/AssetGraphDetailsPane.svelte
@@ -151,6 +151,11 @@
 		// cascade option when > 0. The page computes this from the graph
 		// edges + triggers + currently-open path.
 		downstreamSubscribers?: number
+		// Sister to `requestRunSignal`. When bumped, the bridge calls
+		// `ScriptEditor.runTest({ cascade: true })` — used by the canvas
+		// runnable menu's "Run + trigger N downstream" item when the chosen
+		// script happens to be the currently-open one.
+		requestRunCascadeSignal?: number
 	}
 	let {
 		selection,
@@ -176,19 +181,28 @@
 		pathPrefix = '',
 		onDraftPathChange,
 		requestRemoveSignal,
-		downstreamSubscribers = 0
+		downstreamSubscribers = 0,
+		requestRunCascadeSignal
 	}: Props = $props()
 
 	// Held ref to ScriptEditor so we can route a canvas-side Run dispatch
 	// through .runTest() — gives the test panel logs/result/cancel for
 	// runs initiated from the graph, not just the in-pane Test button.
-	let scriptEditorRef: { runTest: () => Promise<unknown> } | undefined = $state(undefined)
+	let scriptEditorRef: { runTest: (opts?: { cascade?: boolean }) => Promise<unknown> } | undefined =
+		$state(undefined)
 	$effect(() => {
 		// Track the counter; ignore the initial 0/undefined.
 		const sig = requestRunSignal
 		if (sig === undefined || sig === 0) return
 		void scriptEditorRef?.runTest()
 	})
+	$effect(() => {
+		// Cascade-explicit sister signal: same pattern, but forces the
+		// runTest call to opt into the asset-trigger cascade for this run.
+		const sig = requestRunCascadeSignal
+		if (sig === undefined || sig === 0) return
+		void scriptEditorRef?.runTest({ cascade: true })
+	})
 
 	// True when the script that writes to the currently-selected asset is
 	// running right now. Drives the "Recomputing…" banner above the
diff --git a/frontend/src/lib/components/assets/AssetGraph/RunnableNode.svelte b/frontend/src/lib/components/assets/AssetGraph/RunnableNode.svelte
index eda4f44a48..dab555eb53 100644
--- a/frontend/src/lib/components/assets/AssetGraph/RunnableNode.svelte
+++ b/frontend/src/lib/components/assets/AssetGraph/RunnableNode.svelte
@@ -8,7 +8,8 @@
 		Loader2,
 		Play,
 		Timer,
-		Trash2
+		Trash2,
+		Zap
 	} from 'lucide-svelte'
 	import { twMerge } from 'tailwind-merge'
 	import { preventDefault, stopPropagation } from 'svelte/legacy'
@@ -33,8 +34,16 @@
 			// unsaved → runScriptPreview with the locally-cached draft content).
 			// Wired only for script runnables — flows are ignored upstream. When
 			// undefined, the play button is hidden — matches the asset-node
-			// behaviour outside editor contexts.
-			onRunSelf?: () => Promise<string | undefined>
+			// behaviour outside editor contexts. `opts.cascade` lets the
+			// dispatcher decide whether to skip the asset-trigger cascade — the
+			// node's default-click sends `cascade: false` (just this step) to
+			// stay consistent with the editor's Test button.
+			onRunSelf?: (opts?: { cascade?: boolean }) => Promise<string | undefined>
+			// Number of script subscribers that listen on assets this script
+			// writes. When > 0, the hover-menu exposes a "Run + trigger N
+			// downstream" alternative; the round Play button stays a single-
+			// click default. Undefined / 0 hides the cascade menu item.
+			downstreamCount?: number
 			// Called before running so the details pane focuses this script —
 			// mirrors AssetNode.onSelectAsset, keeps the runs/output in view
 			// instead of dispatching into nowhere.
@@ -72,7 +81,7 @@
 	// already running (so the loader doesn't disappear under the cursor).
 	let showRun = $derived(canRun && (hover || selected || running))
 
-	async function runSelf(e: MouseEvent) {
+	async function runSelf(e: MouseEvent, cascade?: boolean) {
 		e.stopPropagation()
 		if (!$workspaceStore || running || !data.onRunSelf) return
 		// Focus this runnable so the details pane opens to its editor — same
@@ -80,7 +89,7 @@
 		if (!selected) data.onSelectSelf?.()
 		running = true
 		try {
-			await data.onRunSelf()
+			await data.onRunSelf(cascade != undefined ? { cascade } : undefined)
 		} catch (err: any) {
 			sendUserToast(`Failed to run: ${err.body ?? err.message}`, true)
 		} finally {
@@ -88,8 +97,23 @@
 		}
 	}
 
-	let menuItems: Item[] = $derived(
-		data.onRequestRemove
+	let menuItems: Item[] = $derived([
+		// Cascade option lives at the top of the menu — the round Run button
+		// is the no-cascade default, this surfaces the alternative when there
+		// are downstream subscribers to fan out to.
+		...(canRun && (data.downstreamCount ?? 0) > 0
+			? [
+					{
+						displayName: `Run + trigger ${data.downstreamCount} downstream`,
+						icon: Zap,
+						action: () => {
+							// Fake MouseEvent-shaped arg so runSelf can stopPropagation.
+							void runSelf({ stopPropagation: () => {} } as MouseEvent, true)
+						}
+					}
+				]
+			: []),
+		...(data.onRequestRemove
 			? [
 					{
 						displayName: data.unsaved ? 'Discard' : 'Delete…',
@@ -98,8 +122,8 @@
 						action: () => data.onRequestRemove?.()
 					}
 				]
-			: []
-	)
+			: [])
+	])
 </script>
 
 <!-- svelte-ignore a11y_no_static_element_interactions -->
diff --git a/frontend/src/routes/(root)/(logged)/pipeline/[folder]/+page.svelte b/frontend/src/routes/(root)/(logged)/pipeline/[folder]/+page.svelte
index 05fb839f75..7c64644f8f 100644
--- a/frontend/src/routes/(root)/(logged)/pipeline/[folder]/+page.svelte
+++ b/frontend/src/routes/(root)/(logged)/pipeline/[folder]/+page.svelte
@@ -923,6 +923,11 @@
 	// into nowhere with only edge animation as feedback. Counter rather
 	// than boolean so back-to-back runs re-fire.
 	let requestRunSignal = $state(0)
+	// Sister counter: bumped instead of requestRunSignal when the canvas user
+	// picks "Run + trigger N downstream" for the currently-open script. Lets
+	// ScriptEditor.runTest run with cascade=true without permanently flipping
+	// its persistent cascade choice.
+	let requestRunCascadeSignal = $state(0)
 	// Counter bumped from the runnable-node action menu to ask the pane to
 	// open its archive/delete confirmation modal for the loaded script.
 	// Counter (vs boolean) so successive triggers re-fire even if the user
@@ -1281,6 +1286,13 @@
 									// immediately — its background poll only kicks in
 									// for already-listed in-flight jobs.
 									if (!$workspaceStore || producer.kind !== 'script') return undefined
+									// Cascade default: same as the Test button — `cascade`
+									// undefined / false skips the asset-trigger dispatch
+									// via `_wmill_skip_asset_dispatch`; explicit `true`
+									// lets the dispatch fire normally. The asset-node
+									// affordance still passes `undefined` (legacy callers),
+									// which we treat as "skip" for consistency.
+									const cascade = producer.cascade === true
 									// If the producer being run is the script currently
 									// edited in the pane, route through ScriptEditor's
 									// Test path — the test panel then shows logs/result
@@ -1292,9 +1304,11 @@
 											? selection.path
 											: undefined)
 									if (openPath === producer.path) {
-										requestRunSignal++
+										if (cascade) requestRunCascadeSignal++
+										else requestRunSignal++
 										return undefined
 									}
+									const skipArg = cascade ? {} : { _wmill_skip_asset_dispatch: true }
 									let jobId: string | undefined
 									if (producer.unsaved) {
 										const draft = drafts.get(producer.path)
@@ -1305,14 +1319,14 @@
 												content: draft.script.content,
 												language: draft.script.language,
 												path: producer.path,
-												args: {}
+												args: { ...skipArg }
 											}
 										})
 									} else {
 										jobId = await JobService.runScriptByPath({
 											workspace: $workspaceStore,
 											path: producer.path,
-											requestBody: {}
+											requestBody: { ...skipArg }
 										})
 									}
 									if (jobId) {
@@ -1373,6 +1387,7 @@
 								}}
 								{requestRemoveSignal}
 								{requestRunSignal}
+								{requestRunCascadeSignal}
 								draftScript={activeDraft?.script}
 								{pathPrefix}
 								onDraftPathChange={renameDraft}