diff --git a/frontend/src/lib/components/assets/AssetGraph/pipelineAiHelpers.test.ts b/frontend/src/lib/components/assets/AssetGraph/pipelineAiHelpers.test.ts
index ef017f0393..713ef8f6b2 100644
--- a/frontend/src/lib/components/assets/AssetGraph/pipelineAiHelpers.test.ts
+++ b/frontend/src/lib/components/assets/AssetGraph/pipelineAiHelpers.test.ts
@@ -8,7 +8,8 @@ import type { AssetGraphResponse } from './types'
 function makeHandle(
 	initial: Array<[string, PipelineDraft]> = [],
 	runnables: Array<{ path: string }> = [],
-	folder = 'x'
+	folder = 'x',
+	triggers: unknown[] = []
 ) {
 	let drafts = new Map(initial)
 	let forgotten: string[] = []
@@ -16,7 +17,7 @@ function makeHandle(
 		getFolder: () => folder,
 		getWorkspace: () => 'w',
 		getResolvedGraph: () =>
-			({ assets: [], runnables, edges: [], triggers: [] }) as unknown as AssetGraphResponse,
+			({ assets: [], runnables, edges: [], triggers }) as unknown as AssetGraphResponse,
 		getDrafts: () => drafts,
 		setDrafts: (next) => (drafts = next),
 		newDraftLocalId: () => 'id',
@@ -207,4 +208,24 @@ describe('pipeline AI direct-draft helpers', () => {
 		expect(d?.script.tag).toBe('custom')
 		expect(d?.script.content).toBe('-- pipeline\nSELECT 2')
 	})
+
+	it("does not take a flow's schedule at the same path for the script's", async () => {
+		const flowSchedule = {
+			trigger_kind: 'schedule',
+			runnable_kind: 'flow',
+			runnable_path: 'f/x/ingest',
+			path: 'f/x/flow_schedule'
+		}
+		const content = '# pipeline\n# on schedule\ndef main():\n    return 1'
+		const { handle } = makeHandle(
+			[['f/x/ingest', draft({ script: { content, language: 'python3' } as any })]],
+			[],
+			'x',
+			[flowSchedule]
+		)
+		expect(await handle.unconfiguredTriggers('f/x/ingest')).toEqual(['schedule'])
+		await expect(
+			handle.setNodeTrigger('f/x/ingest', 'schedule', { schedule: '0 0 6 * * *', timezone: 'UTC' })
+		).resolves.toMatchObject({ path: 'f/x/ingest_schedule' })
+	})
 })
diff --git a/frontend/src/lib/components/assets/AssetGraph/pipelineAiHelpers.ts b/frontend/src/lib/components/assets/AssetGraph/pipelineAiHelpers.ts
index e360a6b577..f84848ee95 100644
--- a/frontend/src/lib/components/assets/AssetGraph/pipelineAiHelpers.ts
+++ b/frontend/src/lib/components/assets/AssetGraph/pipelineAiHelpers.ts
@@ -240,7 +240,11 @@ export function createPipelineAiHelpers(deps: PipelineAiHelperDeps): PipelineAIC
 				.getResolvedGraph()
 				.triggers.filter(
 					(t) =>
-						t.trigger_kind !== 'asset' && t.runnable_path === path && t.path && !t.missing
+						t.trigger_kind !== 'asset' &&
+						t.runnable_kind === 'script' &&
+						t.runnable_path === path &&
+						t.path &&
+						!t.missing
 				)
 				.map((t) => t.trigger_kind)
 		)
@@ -406,6 +410,7 @@ export function createPipelineAiHelpers(deps: PipelineAiHelperDeps): PipelineAIC
 				.triggers.find(
 					(t) =>
 						t.trigger_kind === kind &&
+						t.runnable_kind === 'script' &&
 						t.runnable_path === path &&
 						t.path &&
 						!t.missing &&
diff --git a/frontend/src/lib/components/copilot/chat/pipeline/core.test.ts b/frontend/src/lib/components/copilot/chat/pipeline/core.test.ts
index 57f68df10b..6c4539ef85 100644
--- a/frontend/src/lib/components/copilot/chat/pipeline/core.test.ts
+++ b/frontend/src/lib/components/copilot/chat/pipeline/core.test.ts
@@ -176,6 +176,54 @@ describe('pipeline tools', () => {
 		expect(calls.proposeNode).toBeUndefined()
 	})
 
+	it('build_pipeline_node keeps and records the node when a trigger fails to attach', async () => {
+		const { helpers, calls } = makeHelpers({
+			setNodeTrigger: async () => {
+				throw new Error('path taken')
+			}
+		})
+		const modified: string[] = []
+		const out = await toolByName('build_pipeline_node').fn({
+			args: {
+				path: 'f/analytics/ingest',
+				language: 'python3',
+				content: '# pipeline\n# on schedule\ndef main():\n    return 1',
+				summary: 'Ingest',
+				triggers: [{ kind: 'schedule', config: { schedule: '0 0 6 * * *', timezone: 'UTC' } }]
+			},
+			workspace: 'w',
+			helpers,
+			toolCallbacks: {
+				...noopCallbacks(),
+				onItemModified: (kind, path) => modified.push(`${kind}:${path}`)
+			},
+			toolId: 't'
+		})
+		expect(calls.proposeNode).toHaveLength(1)
+		expect(modified).toEqual(['data_pipeline:f/analytics/data_pipeline'])
+		expect(out).toContain('path taken')
+	})
+
+	it('build_pipeline_node refuses a trigger the content does not declare, before staging', async () => {
+		const { helpers, calls } = makeHelpers()
+		await expect(
+			toolByName('build_pipeline_node').fn({
+				args: {
+					path: 'f/analytics/ingest',
+					language: 'python3',
+					content: '# pipeline\ndef main():\n    return 1',
+					summary: 'Ingest',
+					triggers: [{ kind: 'schedule', config: { schedule: '0 0 6 * * *', timezone: 'UTC' } }]
+				},
+				workspace: 'w',
+				helpers,
+				toolCallbacks: noopCallbacks(),
+				toolId: 't'
+			})
+		).rejects.toThrow(/on schedule/)
+		expect(calls.proposeNode).toBeUndefined()
+	})
+
 	it('build_pipeline_node reports the inferred asset lineage', async () => {
 		const { helpers } = makeHelpers({
 			proposeNode: async (input) => ({
diff --git a/frontend/src/lib/components/copilot/chat/pipeline/core.ts b/frontend/src/lib/components/copilot/chat/pipeline/core.ts
index f47decce08..8d71b00279 100644
--- a/frontend/src/lib/components/copilot/chat/pipeline/core.ts
+++ b/frontend/src/lib/components/copilot/chat/pipeline/core.ts
@@ -15,6 +15,7 @@ import type { PipelineTriggerDraftKind } from '$lib/components/assets/AssetGraph
 import { DRAFTABLE_TRIGGER_KINDS } from '$lib/components/assets/AssetGraph/pipelineTriggerDrafts'
 import { scheduleRequestSchema, triggerRequestSchemas } from '../workspaceToolsZod.gen'
 import { normalizePipelineFolder } from '$lib/utils/pipelineFolder'
+import { parsePipelineAnnotations } from '$lib/components/assets/AssetGraph/parsePipelineAnnotations'
 
 // ============================================================================
 // Pipeline AI chat tools.
@@ -437,11 +438,16 @@ export const pipelineTools: SessionTool<PipelineToolHelpers>[] = [
 			const { path, language, content, summary, output_kind, triggers } =
 				buildPipelineNodeSchema.parse(args)
 			const pipeline = await pipelineForPath(helpers, path)
-			// Validated before the node is staged, so a bad config leaves nothing half-built.
-			const configs = (triggers ?? []).map((t) => ({
-				kind: t.kind,
-				config: validateTriggerConfig(t.kind, t.config, path)
-			}))
+			// Checked before the node is staged, so a bad trigger leaves nothing half-built.
+			const declared = new Set(parsePipelineAnnotations(content).nativeTriggers.map((n) => n.kind))
+			const configs = (triggers ?? []).map((t) => {
+				if (!declared.has(t.kind)) {
+					throw new Error(
+						`The content declares no \`on ${t.kind}\`, so a ${t.kind} trigger has nothing to bind to. Add the annotation line or drop that trigger. Nothing was built.`
+					)
+				}
+				return { kind: t.kind, config: validateTriggerConfig(t.kind, t.config, path) }
+			})
 			toolCallbacks.setToolStatus(toolId, { content: `Building node '${path}'...` })
 			const { detectedReads, detectedWrites } = await pipeline.proposeNode({
 				path,
@@ -450,19 +456,29 @@ export const pipelineTools: SessionTool<PipelineToolHelpers>[] = [
 				summary,
 				outputKind: output_kind as PipelineOutputKind | undefined
 			})
-			const attached: string[] = []
-			for (const t of configs) {
-				const { path: triggerPath } = await pipeline.setNodeTrigger(path, t.kind, t.config)
-				attached.push(`${t.kind} '${triggerPath}'`)
-			}
+			// Recorded as soon as it is staged: a trigger that fails below leaves the node.
 			recordPipelineModified(toolCallbacks, pipeline)
+			const attached: string[] = []
+			const failed: string[] = []
+			for (const t of configs) {
+				try {
+					const { path: triggerPath } = await pipeline.setNodeTrigger(path, t.kind, t.config)
+					attached.push(`${t.kind} '${triggerPath}'`)
+				} catch (e) {
+					failed.push(`${t.kind}: ${e instanceof Error ? e.message : String(e)}`)
+				}
+			}
 			toolCallbacks.setToolStatus(toolId, {
 				content: `Added draft node '${path}'`,
 				result: 'Success'
 			})
-			const attachedNote = attached.length
-				? ` Attached trigger draft${attached.length > 1 ? 's' : ''}: ${attached.join(', ')}.`
-				: ''
+			const attachedNote =
+				(attached.length
+					? ` Attached trigger draft${attached.length > 1 ? 's' : ''}: ${attached.join(', ')}.`
+					: '') +
+				(failed.length
+					? ` The node was built, but these triggers were not attached — fix them with set_pipeline_trigger: ${failed.join('; ')}.`
+					: '')
 			return `Pipeline node '${path}' added as an unsaved draft on the canvas. It is not deployed — the user deploys it.${attachedNote}${inferredLineageNote(detectedReads, detectedWrites)}${unconfiguredTriggersNote(path, await pipeline.unconfiguredTriggers(path))}`
 		}
 	},