diff --git a/frontend/src/lib/components/copilot/chat/flow/FlowAIChat.svelte b/frontend/src/lib/components/copilot/chat/flow/FlowAIChat.svelte
index 97af435dda..37db9a90ba 100644
--- a/frontend/src/lib/components/copilot/chat/flow/FlowAIChat.svelte
+++ b/frontend/src/lib/components/copilot/chat/flow/FlowAIChat.svelte
@@ -196,14 +196,15 @@
 			return { errorCount: 0, warningCount: 0, errors: [], warnings: [] }
 		},
 
-		setFlowJson: async ({ modules, schema, preprocessorModule, failureModule, groups }) => {
+		setFlowJson: async ({ modules, schema, preprocessorModule, failureModule, groups, notes }) => {
 			try {
 				if (
 					modules !== undefined ||
 					schema !== undefined ||
 					preprocessorModule !== undefined ||
 					failureModule !== undefined ||
-					groups !== undefined
+					groups !== undefined ||
+					notes !== undefined
 				) {
 					// Take snapshot of current flowStore and set as beforeFlow
 					if (!diffManager?.hasPendingChanges) {
@@ -218,7 +219,8 @@
 					schema,
 					preprocessorModule,
 					failureModule,
-					groups
+					groups,
+					notes
 				})
 
 				// Refresh the state store to update UI
diff --git a/frontend/src/lib/components/copilot/chat/flow/core.ts b/frontend/src/lib/components/copilot/chat/flow/core.ts
index 77fc955d56..af616cca84 100644
--- a/frontend/src/lib/components/copilot/chat/flow/core.ts
+++ b/frontend/src/lib/components/copilot/chat/flow/core.ts
@@ -32,7 +32,13 @@ import type { ContextElement } from '../context'
 import type { ExtendedOpenFlow } from '$lib/components/flows/types'
 import { findModuleInFlow, findModuleInModules } from '$lib/components/flows/flowTree'
 import { createInlineScriptSession, type InlineScriptSession } from './inlineScriptsUtils'
-import { validateFlowGroups, type FlowGroup, type FlowJsonUpdateResult } from './helperUtils'
+import {
+	validateFlowGroups,
+	validateFlowNotes,
+	type FlowGroup,
+	type FlowNote,
+	type FlowJsonUpdateResult
+} from './helperUtils'
 import { flowModuleSchema } from './openFlowZod.gen'
 import { collectAllFlowModuleIdsFromModules } from '$lib/components/flows/flowTree'
 import {
@@ -50,6 +56,7 @@ type FlowJsonUpdate = {
 	preprocessorModule?: FlowModule | null
 	failureModule?: FlowModule | null
 	groups?: FlowGroup[] | null
+	notes?: FlowNote[] | null
 }
 
 function formatEmptyInlineScriptWarning({
@@ -179,6 +186,13 @@ const setFlowJsonToolSchema = z.object({
 		.nullable()
 		.describe(
 			'JSON string containing the optional array of semantic flow groups. Each group has summary, note, autocollapse, start_id, end_id, color. color MUST be one of: yellow, blue, green, purple, pink, orange, red, cyan, lime, gray — never hex codes or other strings. Pass null to clear groups.'
+		),
+	notes: z
+		.string()
+		.optional()
+		.nullable()
+		.describe(
+			'JSON string containing the optional array of free-floating sticky notes attached to the flow. Use notes to surface important flow-wide information (what the flow does, key assumptions, warnings, TODOs). Each note has id (unique string), text (markdown), color (one of: yellow, blue, green, purple, pink, orange, red, cyan, lime, gray — never hex codes), and optional position {x,y} and size {width,height} — omit both and the editor places and sizes the note automatically. Always use type "free". The "group" note type is DEPRECATED — to segment a complex flow into labelled, colored sections use the `groups` field instead (each group carries its own note and color). Pass null to clear notes.'
 		)
 })
 
@@ -548,7 +562,8 @@ export const flowTools: Tool<FlowAIChatHelpers>[] = [
 				schema: parsedFlow.schema,
 				preprocessorModule: parsedFlow.preprocessor_module,
 				failureModule: parsedFlow.failure_module,
-				groups: parsedFlow.groups
+				groups: parsedFlow.groups,
+				notes: parsedFlow.notes
 			})
 			const warning = formatEmptyInlineScriptWarning(updateResult)
 
@@ -651,13 +666,14 @@ export const flowTools: Tool<FlowAIChatHelpers>[] = [
 		showDetails: true,
 		showFade: true,
 		fn: async ({ args, helpers, toolId, toolCallbacks }) => {
-			const { modules, schema, preprocessor_module, failure_module, groups } = args
+			const { modules, schema, preprocessor_module, failure_module, groups, notes } = args
 
 			let parsedModules: FlowModule[] | null | undefined
 			let parsedSchema: Record<string, any> | null | undefined
 			let parsedPreprocessorModule: FlowModule | null | undefined
 			let parsedFailureModule: FlowModule | null | undefined
 			let parsedGroups: FlowGroup[] | null | undefined
+			let parsedNotes: FlowNote[] | null | undefined
 
 			// Parse JSON strings
 			parsedModules = parseOptionalJsonArg(modules, 'modules') as FlowModule[] | null | undefined
@@ -674,6 +690,7 @@ export const flowTools: Tool<FlowAIChatHelpers>[] = [
 				| null
 				| undefined
 			parsedGroups = parseOptionalJsonArg(groups, 'groups') as FlowGroup[] | null | undefined
+			parsedNotes = parseOptionalJsonArg(notes, 'notes') as FlowNote[] | null | undefined
 			if (parsedModules === null) {
 				parsedModules = undefined
 			}
@@ -702,11 +719,16 @@ export const flowTools: Tool<FlowAIChatHelpers>[] = [
 			)
 			parsedFailureModule = validateSpecialFlowModule(parsedFailureModule, 'failure_module')
 
-			if (parsedGroups !== undefined) {
+			if (parsedGroups !== undefined || parsedNotes !== undefined) {
 				const effectiveModules =
 					parsedModules ?? helpers.getFlowAndSelectedId().flow.value.modules ?? []
 				const moduleIdsForGroups = new Set(collectAllFlowModuleIdsFromModules(effectiveModules))
-				parsedGroups = validateFlowGroups(parsedGroups, moduleIdsForGroups)
+				if (parsedGroups !== undefined) {
+					parsedGroups = validateFlowGroups(parsedGroups, moduleIdsForGroups)
+				}
+				if (parsedNotes !== undefined) {
+					parsedNotes = validateFlowNotes(parsedNotes, moduleIdsForGroups)
+				}
 			}
 
 			const ids = [
@@ -729,7 +751,8 @@ export const flowTools: Tool<FlowAIChatHelpers>[] = [
 					? { preprocessorModule: parsedPreprocessorModule }
 					: {}),
 				...(parsedFailureModule !== undefined ? { failureModule: parsedFailureModule } : {}),
-				...(parsedGroups !== undefined ? { groups: parsedGroups } : {})
+				...(parsedGroups !== undefined ? { groups: parsedGroups } : {}),
+				...(parsedNotes !== undefined ? { notes: parsedNotes } : {})
 			})
 			const warning = formatEmptyInlineScriptWarning(updateResult)
 
@@ -831,7 +854,7 @@ export function prepareFlowSystemMessage(customPrompt?: string): ChatCompletionS
 Use \`patch_flow_json\` for small, localized changes when you can target an exact snippet from the \`CURRENT FLOW JSON COMPACT\` block below.
 
 Always copy the exact search text from the \`CURRENT FLOW JSON COMPACT\` block below.
-The compact JSON is a single object with \`modules\`, \`schema\`, \`preprocessor_module\`, \`failure_module\`, and \`groups\` keys.
+The compact JSON is a single object with \`modules\`, \`schema\`, \`preprocessor_module\`, \`failure_module\`, \`groups\`, and \`notes\` keys.
 
 **Parameters:**
 - \`old_string\`: Exact JSON text to find
@@ -859,7 +882,16 @@ Use the \`set_flow_json\` tool to set the entire flow structure at once. Provide
 - \`schema\`: Flow input schema in JSON Schema format (optional)
 - \`preprocessor_module\`: Special module that runs before \`modules\` (optional, separate from \`modules\`)
 - \`failure_module\`: Special module that runs on failure (optional, separate from \`modules\`)
-- \`groups\`: Array of semantic groups for organizing modules in the editor (optional). Each group has \`summary\` (display name), \`note\` (markdown description shown below the group header — attached directly to the group, not a separate sticky note), \`autocollapse\`, \`start_id\`, \`end_id\`, and \`color\`. \`start_id\` and \`end_id\` must reference existing module IDs in the flow (not \`preprocessor\` or \`failure\`). \`color\` MUST be one of these exact names: \`yellow\`, \`blue\`, \`green\`, \`purple\`, \`pink\`, \`orange\`, \`red\`, \`cyan\`, \`lime\`, \`gray\` — do NOT use hex codes, CSS colors, or any other strings. Omit \`color\` entirely if no preference and the editor will assign one automatically. Groups do not affect execution — they provide naming and collapsibility in the editor. Pass \`null\` to clear existing groups.
+- \`groups\`: Array of semantic groups for organizing modules in the editor (optional, but **strongly recommended** — proactively segment any non-trivial flow into groups so it reads clearly; don't wait to be asked). Each group has \`summary\` (display name), \`note\` (markdown description shown below the group header — attached directly to the group, not a separate sticky note), \`autocollapse\`, \`start_id\`, \`end_id\`, and \`color\`. \`start_id\` and \`end_id\` must reference existing module IDs in the flow (not \`preprocessor\` or \`failure\`). \`color\` MUST be one of these exact names: \`yellow\`, \`blue\`, \`green\`, \`purple\`, \`pink\`, \`orange\`, \`red\`, \`cyan\`, \`lime\`, \`gray\` — do NOT use hex codes, CSS colors, or any other strings. Omit \`color\` entirely if no preference and the editor will assign one automatically. Groups do not affect execution — they provide naming and collapsibility in the editor. Pass \`null\` to clear existing groups.
+- \`notes\`: Array of free-floating sticky notes shown in the editor (optional). Each note has \`id\` (unique string), \`text\` (markdown content), \`color\` (same palette as groups: \`yellow\`, \`blue\`, \`green\`, \`purple\`, \`pink\`, \`orange\`, \`red\`, \`cyan\`, \`lime\`, \`gray\` — never hex codes), and optional \`position\` {x, y} / \`size\` {width, height} (omit both — the editor auto-places and sizes the note). Always set \`type\` to \`free\`. The \`group\` note type is **deprecated** — do not create group notes; use the \`groups\` field to segment a flow instead. Notes are documentation only and do not affect execution. Pass \`null\` to clear existing notes.
+
+### When to use notes vs groups
+
+**Strongly prefer \`groups\` to organize flows.** Groups are the primary way to make a flow readable: whenever a flow has more than a couple of steps, or any time consecutive steps form a logical stage (e.g. "fetch", "transform", "notify"), segment them into \`groups\`. Each group spans a range of steps (\`start_id\`..\`end_id\`), carries its own \`summary\`, \`note\` (markdown under the group header), and \`color\`, and can be collapsed. Proactively add or update groups when building or restructuring a flow — do not wait to be asked. Aim for every meaningful step to belong to a semantic group.
+
+- **\`groups\` (default, use liberally):** segment a flow into labelled semantic sections. This is the main organizational tool — reach for it on essentially any non-trivial flow, not just "complex" ones.
+- **\`notes\` (free sticky notes, use sparingly):** reserve for important flow-wide information that does not belong to a specific span of steps — overall purpose, key assumptions, warnings, or TODOs. Usually a single note is enough; do not use notes to label sequences of steps (that is what \`groups\` are for).
+- Do **not** use \`group\`-type notes (deprecated) — \`groups\` is the supported way to group steps.
 
 **Example - Simple flow:**
 \`\`\`javascript
diff --git a/frontend/src/lib/components/copilot/chat/flow/editableFlowJson.ts b/frontend/src/lib/components/copilot/chat/flow/editableFlowJson.ts
index a4b0ea72d5..2f1cb5a699 100644
--- a/frontend/src/lib/components/copilot/chat/flow/editableFlowJson.ts
+++ b/frontend/src/lib/components/copilot/chat/flow/editableFlowJson.ts
@@ -3,7 +3,7 @@ import type { FlowModule, FlowValue } from '$lib/gen'
 import { collectAllFlowModuleIdsFromModules } from '$lib/components/flows/flowTree'
 import { SPECIAL_MODULE_IDS } from '../shared'
 import type { InlineScriptSession } from './inlineScriptsUtils'
-import { validateFlowGroups, type FlowGroup } from './helperUtils'
+import { validateFlowGroups, validateFlowNotes, type FlowGroup, type FlowNote } from './helperUtils'
 import { flowModuleSchema, flowModulesSchema } from './openFlowZod.gen'
 
 /**
@@ -19,6 +19,7 @@ export type EditableFlowJson = {
 	preprocessor_module: FlowModule | null
 	failure_module: FlowModule | null
 	groups: FlowGroup[] | null
+	notes: FlowNote[] | null
 }
 
 /** Optional input to the rich-error path of `validateEditableFlowJson`. */
@@ -145,8 +146,10 @@ function formatJsonSchemaForError(jsonSchema: any): string {
 	if (jsonSchema.enum) {
 		return `one of: ${jsonSchema.enum.map((v: any) => JSON.stringify(v)).join(', ')}`
 	}
-	if (jsonSchema.oneOf) return jsonSchema.oneOf.map((s: any) => formatJsonSchemaForError(s)).join(' | ')
-	if (jsonSchema.anyOf) return jsonSchema.anyOf.map((s: any) => formatJsonSchemaForError(s)).join(' | ')
+	if (jsonSchema.oneOf)
+		return jsonSchema.oneOf.map((s: any) => formatJsonSchemaForError(s)).join(' | ')
+	if (jsonSchema.anyOf)
+		return jsonSchema.anyOf.map((s: any) => formatJsonSchemaForError(s)).join(' | ')
 	if (jsonSchema.description) return jsonSchema.description
 	return jsonSchema.type || JSON.stringify(jsonSchema)
 }
@@ -177,7 +180,10 @@ function getExpectedFormat(schema: z.ZodType): string | null {
 	return null
 }
 
-export function validateFlowModules(rawModules: unknown, ctx: SchemaErrorContext = {}): FlowModule[] {
+export function validateFlowModules(
+	rawModules: unknown,
+	ctx: SchemaErrorContext = {}
+): FlowModule[] {
 	if (!Array.isArray(rawModules)) {
 		throw new Error('Flow modules must be an array')
 	}
@@ -275,6 +281,7 @@ export function validateEditableFlowJson(
 	const failureModule = validateOptionalFlowModule(flow.failure_module, 'failure_module')
 	const groupModuleIds = new Set(collectAllFlowModuleIdsFromModules(modules))
 	const groups = validateFlowGroups(flow.groups, groupModuleIds)
+	const notes = validateFlowNotes(flow.notes, groupModuleIds)
 
 	if (preprocessorModule) {
 		if (preprocessorModule.id !== SPECIAL_MODULE_IDS.PREPROCESSOR) {
@@ -316,7 +323,8 @@ export function validateEditableFlowJson(
 		schema,
 		preprocessor_module: preprocessorModule,
 		failure_module: failureModule,
-		groups
+		groups,
+		notes
 	}
 }
 
@@ -371,7 +379,8 @@ export function buildEditableFlowJson(
 		schema: flow.schema ?? null,
 		preprocessor_module: preprocessorModule ?? null,
 		failure_module: failureModule ?? null,
-		groups: flow.value.groups ?? null
+		groups: flow.value.groups ?? null,
+		notes: flow.value.notes ?? null
 	}
 }
 
@@ -407,6 +416,7 @@ export function applyEditableFlowJsonToFlow(
 		preprocessor_module:
 			restoreSpecialRawscriptModule(editable.preprocessor_module, session) ?? undefined,
 		failure_module: restoreSpecialRawscriptModule(editable.failure_module, session) ?? undefined,
-		groups: editable.groups ?? undefined
+		groups: editable.groups ?? undefined,
+		notes: editable.notes ?? undefined
 	}
 }
diff --git a/frontend/src/lib/components/copilot/chat/flow/helperUtils.test.ts b/frontend/src/lib/components/copilot/chat/flow/helperUtils.test.ts
index 75749013a8..6dd0e1f791 100644
--- a/frontend/src/lib/components/copilot/chat/flow/helperUtils.test.ts
+++ b/frontend/src/lib/components/copilot/chat/flow/helperUtils.test.ts
@@ -3,7 +3,8 @@ import type { FlowModule } from '$lib/gen'
 import {
 	applyFlowJsonUpdate,
 	updateRawScriptModuleContent,
-	validateFlowGroups
+	validateFlowGroups,
+	validateFlowNotes
 } from './helperUtils'
 import { createInlineScriptSession } from './inlineScriptsUtils'
 
@@ -222,6 +223,70 @@ describe('applyFlowJsonUpdate', () => {
 		expect((flow.value as any).groups).toEqual(existingGroups)
 	})
 
+	it('persists notes passed in the flow json update', () => {
+		const flow = {
+			value: {
+				modules: [makeRawScriptModule('fetch_data', 'existing code')]
+			}
+		}
+		const inlineScriptSession = createInlineScriptSession()
+		inlineScriptSession.set('fetch_data', 'existing code')
+
+		applyFlowJsonUpdate(flow as any, inlineScriptSession, {
+			notes: [
+				{
+					id: 'note_1',
+					text: 'Remember to set the API key',
+					color: 'yellow',
+					type: 'free'
+				} as any
+			]
+		})
+
+		expect((flow.value as any).notes).toEqual([
+			{
+				id: 'note_1',
+				text: 'Remember to set the API key',
+				color: 'yellow',
+				type: 'free'
+			}
+		])
+	})
+
+	it('clears notes when an empty array or null is passed', () => {
+		const flow = {
+			value: {
+				modules: [],
+				notes: [{ id: 'n', text: 't', color: 'yellow', type: 'free' }]
+			}
+		}
+		const inlineScriptSession = createInlineScriptSession()
+
+		applyFlowJsonUpdate(flow as any, inlineScriptSession, { notes: [] })
+		expect((flow.value as any).notes).toBeUndefined()
+		;(flow.value as any).notes = [{ id: 'n', text: 't', color: 'yellow', type: 'free' }]
+		applyFlowJsonUpdate(flow as any, inlineScriptSession, { notes: null })
+		expect((flow.value as any).notes).toBeUndefined()
+	})
+
+	it('leaves notes untouched when not provided in the update', () => {
+		const existingNotes = [{ id: 'n', text: 't', color: 'yellow', type: 'free' }]
+		const flow = {
+			value: {
+				modules: [makeRawScriptModule('a', 'existing code')],
+				notes: existingNotes
+			}
+		}
+		const inlineScriptSession = createInlineScriptSession()
+		inlineScriptSession.set('a', 'existing code')
+
+		applyFlowJsonUpdate(flow as any, inlineScriptSession, {
+			modules: [makeRawScriptModule('a', 'inline_script.a')]
+		})
+
+		expect((flow.value as any).notes).toEqual(existingNotes)
+	})
+
 	it('updates ai agent rawscript tools in place when changing module code', () => {
 		const flow = {
 			value: {
@@ -319,3 +384,162 @@ describe('validateFlowGroups', () => {
 		expect(result).toEqual([{ start_id: 'a', end_id: 'b' }])
 	})
 })
+
+describe('validateFlowNotes', () => {
+	it('returns null for null/undefined input', () => {
+		expect(validateFlowNotes(null)).toBeNull()
+		expect(validateFlowNotes(undefined)).toBeNull()
+	})
+
+	it('rejects non-array input', () => {
+		expect(() => validateFlowNotes({})).toThrow('Flow notes must be an array')
+	})
+
+	it('rejects a note that is not an object', () => {
+		expect(() => validateFlowNotes(['nope'])).toThrow('Invalid note at index 0: must be an object')
+	})
+
+	it('rejects a note with a missing or non-string id', () => {
+		expect(() => validateFlowNotes([{ text: 't' }])).toThrow(
+			'Invalid note at index 0: id must be a non-empty string'
+		)
+		expect(() => validateFlowNotes([{ id: '', text: 't' }])).toThrow(
+			'Invalid note at index 0: id must be a non-empty string'
+		)
+	})
+
+	it('rejects duplicate note ids', () => {
+		expect(() =>
+			validateFlowNotes([
+				{ id: 'n', text: 'a' },
+				{ id: 'n', text: 'b' }
+			])
+		).toThrow('Invalid note at index 1: duplicate note id "n"')
+	})
+
+	it('rejects a non-string text', () => {
+		expect(() => validateFlowNotes([{ id: 'n', text: 42 }])).toThrow(
+			'Invalid note at index 0: text must be a string'
+		)
+	})
+
+	it('rejects an invalid type', () => {
+		expect(() => validateFlowNotes([{ id: 'n', text: 't', type: 'sticky' }])).toThrow(
+			'Invalid note at index 0: type must be "free" or "group"'
+		)
+	})
+
+	it('rejects an unknown color name', () => {
+		expect(() => validateFlowNotes([{ id: 'n', text: 't', color: '#ffff00' }])).toThrow(
+			/color must be one of/
+		)
+	})
+
+	it('defaults type to free and color to the default note color', () => {
+		const [note] = validateFlowNotes([{ id: 'n', text: 't' }])!
+		expect(note).toMatchObject({ id: 'n', text: 't', type: 'free', color: 'green' })
+	})
+
+	it('preserves a provided palette color rather than overriding it', () => {
+		const [note] = validateFlowNotes([{ id: 'n', text: 't', color: 'purple' }])!
+		expect(note).toMatchObject({ id: 'n', text: 't', type: 'free', color: 'purple' })
+	})
+
+	it('gives a free note missing geometry a concrete position and size', () => {
+		const [note] = validateFlowNotes([{ id: 'n', text: 't' }])!
+		expect(note.position).toEqual({ x: expect.any(Number), y: expect.any(Number) })
+		expect(note.size).toEqual({ width: expect.any(Number), height: expect.any(Number) })
+		expect(note.size!.width).toBeGreaterThan(0)
+		expect(note.size!.height).toBeGreaterThan(0)
+	})
+
+	it('staggers the default y position of multiple geometry-less free notes', () => {
+		const notes = validateFlowNotes([
+			{ id: 'a', text: 't' },
+			{ id: 'b', text: 't' }
+		])!
+		expect(notes[0].position!.y).not.toEqual(notes[1].position!.y)
+	})
+
+	it('does not override a free note that already has geometry', () => {
+		const [note] = validateFlowNotes([
+			{ id: 'n', text: 't', position: { x: 5, y: 6 }, size: { width: 400, height: 90 } }
+		])!
+		expect(note.position).toEqual({ x: 5, y: 6 })
+		expect(note.size).toEqual({ width: 400, height: 90 })
+	})
+
+	it('does not add geometry to group notes', () => {
+		const [note] = validateFlowNotes([
+			{ id: 'n', text: 't', type: 'group', contained_node_ids: [] }
+		])!
+		expect(note.position).toBeUndefined()
+		expect(note.size).toBeUndefined()
+	})
+
+	it('rejects a malformed position', () => {
+		expect(() => validateFlowNotes([{ id: 'n', text: 't', position: { x: 1 } }])).toThrow(
+			'Invalid note at index 0: position must be an object with numeric x and y'
+		)
+		expect(() => validateFlowNotes([{ id: 'n', text: 't', position: [1, 2] }])).toThrow(
+			'Invalid note at index 0: position must be an object with numeric x and y'
+		)
+	})
+
+	it('rejects a malformed size', () => {
+		expect(() => validateFlowNotes([{ id: 'n', text: 't', size: { width: '10' } }])).toThrow(
+			'Invalid note at index 0: size must be an object with numeric width and height'
+		)
+	})
+
+	it('accepts a free note with valid position and size', () => {
+		const result = validateFlowNotes([
+			{
+				id: 'n',
+				text: 't',
+				color: 'blue',
+				position: { x: 10, y: 20 },
+				size: { width: 300, height: 80 }
+			}
+		])
+		expect(result).toEqual([
+			{
+				id: 'n',
+				text: 't',
+				type: 'free',
+				color: 'blue',
+				position: { x: 10, y: 20 },
+				size: { width: 300, height: 80 }
+			}
+		])
+	})
+
+	it('rejects group note contained_node_ids that are not strings', () => {
+		expect(() =>
+			validateFlowNotes([{ id: 'n', text: 't', type: 'group', contained_node_ids: [1] }])
+		).toThrow('Invalid note at index 0: contained_node_ids must be an array of strings')
+	})
+
+	it('rejects group note contained_node_ids that do not match a module', () => {
+		const moduleIds = new Set(['a', 'b'])
+		expect(() =>
+			validateFlowNotes(
+				[{ id: 'n', text: 't', type: 'group', contained_node_ids: ['missing'] }],
+				moduleIds
+			)
+		).toThrow(
+			'Invalid note at index 0: contained_node_ids "missing" does not match any flow module'
+		)
+	})
+
+	it('accepts a valid group note whose contained ids are all modules', () => {
+		const moduleIds = new Set(['a', 'b'])
+		const result = validateFlowNotes(
+			[{ id: 'n', text: 't', color: 'blue', type: 'group', contained_node_ids: ['a', 'b'] }],
+			moduleIds
+		)
+		expect(result).toEqual([
+			{ id: 'n', text: 't', color: 'blue', type: 'group', contained_node_ids: ['a', 'b'] }
+		])
+	})
+})
diff --git a/frontend/src/lib/components/copilot/chat/flow/helperUtils.ts b/frontend/src/lib/components/copilot/chat/flow/helperUtils.ts
index f424490d24..35b6aae909 100644
--- a/frontend/src/lib/components/copilot/chat/flow/helperUtils.ts
+++ b/frontend/src/lib/components/copilot/chat/flow/helperUtils.ts
@@ -1,19 +1,26 @@
-import type { FlowModule, FlowValue, OpenFlow, RawScript } from '$lib/gen'
+import type { FlowModule, FlowNote, FlowValue, OpenFlow, RawScript } from '$lib/gen'
 import { forEachFlowModule } from '$lib/components/flows/dfs'
 import { findModuleInFlow } from '$lib/components/flows/flowTree'
-import { NoteColor } from '$lib/components/graph/noteColors'
+import {
+	DEFAULT_NOTE_COLOR,
+	MIN_NOTE_HEIGHT,
+	MIN_NOTE_WIDTH,
+	NoteColor
+} from '$lib/components/graph/noteColors'
 import type { InlineScriptSession } from './inlineScriptsUtils'
 
-/** Allowed group color names — matches the NoteColor palette the group
- * editor uses. Other strings would render with default-blue styling at best
- * and break the color picker UI at worst. */
-const ALLOWED_GROUP_COLORS = new Set<string>(Object.values(NoteColor))
+/** Allowed note/group color names — matches the NoteColor palette the note and
+ * group editors use. The note renderer keys `NOTE_COLORS` by these exact names,
+ * so other strings (hex codes, CSS colors) render with no styling at best and
+ * break the color picker UI at worst. */
+const ALLOWED_NOTE_COLORS = new Set<string>(Object.values(NoteColor))
 
 type FlowLike = Pick<OpenFlow, 'value'> & {
 	schema?: Record<string, any>
 }
 
 export type FlowGroup = NonNullable<FlowValue['groups']>[number]
+export type { FlowNote }
 
 export interface FlowJsonUpdate {
 	modules?: FlowModule[]
@@ -21,6 +28,7 @@ export interface FlowJsonUpdate {
 	preprocessorModule?: FlowModule | null
 	failureModule?: FlowModule | null
 	groups?: FlowGroup[] | null
+	notes?: FlowNote[] | null
 }
 
 export interface FlowJsonUpdateResult {
@@ -78,9 +86,9 @@ export function validateFlowGroups(
 			}
 		}
 		if (g.color !== undefined && g.color !== null) {
-			if (typeof g.color !== 'string' || !ALLOWED_GROUP_COLORS.has(g.color)) {
+			if (typeof g.color !== 'string' || !ALLOWED_NOTE_COLORS.has(g.color)) {
 				throw new Error(
-					`Invalid group at index ${index}: color must be one of ${[...ALLOWED_GROUP_COLORS].join(', ')}`
+					`Invalid group at index ${index}: color must be one of ${[...ALLOWED_NOTE_COLORS].join(', ')}`
 				)
 			}
 		}
@@ -88,10 +96,138 @@ export function validateFlowGroups(
 	})
 }
 
+/**
+ * Validate the optional array of sticky notes the agent attached to the flow.
+ * Notes are editor-only annotations and do not affect execution.
+ *
+ * `free` notes are the supported kind (standalone canvas annotations). The
+ * `group` note type is deprecated for creation — the chat prompt steers the
+ * agent toward `groups` instead — but it is still ACCEPTED here so flows that
+ * already contain group notes round-trip cleanly through `patch_flow_json` /
+ * `set_flow_json` rather than being rejected. When `moduleIds` is provided,
+ * every `contained_node_ids` entry of a `group` note must reference an existing
+ * module.
+ *
+ * A provided palette `color` is always preserved as-is; the default is only
+ * filled in when a note omits `color` entirely (FlowNote.color is required).
+ *
+ * Free notes are also given a concrete `position` and `size` when missing. A
+ * free note without geometry is not draggable/resizable in the editor (you'd
+ * have to resize it first to give it a size) — UI-created notes always set both,
+ * so agent-created notes must too. Provided geometry is preserved untouched.
+ */
+export function validateFlowNotes(rawNotes: unknown, moduleIds?: Set<string>): FlowNote[] | null {
+	if (rawNotes == null) {
+		return null
+	}
+
+	if (!Array.isArray(rawNotes)) {
+		throw new Error('Flow notes must be an array')
+	}
+
+	const seenIds = new Set<string>()
+	return rawNotes.map((note, index) => {
+		if (!note || typeof note !== 'object' || Array.isArray(note)) {
+			throw new Error(`Invalid note at index ${index}: must be an object`)
+		}
+		const n = note as Record<string, unknown>
+		if (typeof n.id !== 'string' || !n.id) {
+			throw new Error(`Invalid note at index ${index}: id must be a non-empty string`)
+		}
+		if (seenIds.has(n.id)) {
+			throw new Error(`Invalid note at index ${index}: duplicate note id "${n.id}"`)
+		}
+		seenIds.add(n.id)
+		if (typeof n.text !== 'string') {
+			throw new Error(`Invalid note at index ${index}: text must be a string`)
+		}
+		const type = n.type ?? 'free'
+		if (type !== 'free' && type !== 'group') {
+			throw new Error(`Invalid note at index ${index}: type must be "free" or "group"`)
+		}
+		if (n.color !== undefined && n.color !== null) {
+			if (typeof n.color !== 'string' || !ALLOWED_NOTE_COLORS.has(n.color)) {
+				throw new Error(
+					`Invalid note at index ${index}: color must be one of ${[...ALLOWED_NOTE_COLORS].join(', ')}`
+				)
+			}
+		}
+		if (n.position !== undefined && n.position !== null) {
+			const p = n.position as Record<string, unknown>
+			if (
+				typeof p !== 'object' ||
+				Array.isArray(n.position) ||
+				typeof p.x !== 'number' ||
+				typeof p.y !== 'number'
+			) {
+				throw new Error(
+					`Invalid note at index ${index}: position must be an object with numeric x and y`
+				)
+			}
+		}
+		if (n.size !== undefined && n.size !== null) {
+			const s = n.size as Record<string, unknown>
+			if (
+				typeof s !== 'object' ||
+				Array.isArray(n.size) ||
+				typeof s.width !== 'number' ||
+				typeof s.height !== 'number'
+			) {
+				throw new Error(
+					`Invalid note at index ${index}: size must be an object with numeric width and height`
+				)
+			}
+		}
+		if (type === 'group' && n.contained_node_ids !== undefined) {
+			if (
+				!Array.isArray(n.contained_node_ids) ||
+				n.contained_node_ids.some((id) => typeof id !== 'string')
+			) {
+				throw new Error(
+					`Invalid note at index ${index}: contained_node_ids must be an array of strings`
+				)
+			}
+			if (moduleIds) {
+				for (const id of n.contained_node_ids as string[]) {
+					if (!moduleIds.has(id)) {
+						throw new Error(
+							`Invalid note at index ${index}: contained_node_ids "${id}" does not match any flow module`
+						)
+					}
+				}
+			}
+		}
+		const normalized = {
+			...(n as FlowNote),
+			type,
+			// Preserve a provided color; only seed the default when omitted.
+			color: typeof n.color === 'string' ? n.color : DEFAULT_NOTE_COLOR
+		} as FlowNote
+
+		// Free notes need explicit geometry to be draggable/resizable. Place
+		// missing ones to the left of the flow column, staggered by index so
+		// several new notes don't land exactly on top of each other. Group notes
+		// derive their layout from contained nodes, so they are left alone.
+		if (type === 'free') {
+			if (normalized.position == null) {
+				normalized.position = {
+					x: -(MIN_NOTE_WIDTH + 100),
+					y: index * (MIN_NOTE_HEIGHT + 24)
+				}
+			}
+			if (normalized.size == null) {
+				normalized.size = { width: MIN_NOTE_WIDTH, height: MIN_NOTE_HEIGHT }
+			}
+		}
+
+		return normalized
+	})
+}
+
 export function applyFlowJsonUpdate(
 	flow: FlowLike,
 	inlineScriptSession: InlineScriptSession,
-	{ modules, schema, preprocessorModule, failureModule, groups }: FlowJsonUpdate
+	{ modules, schema, preprocessorModule, failureModule, groups, notes }: FlowJsonUpdate
 ): FlowJsonUpdateResult {
 	const emptyInlineScriptModuleIds = new Set<string>()
 
@@ -125,6 +261,10 @@ export function applyFlowJsonUpdate(
 		flow.value.groups = groups == null || groups.length === 0 ? undefined : groups
 	}
 
+	if (notes !== undefined) {
+		flow.value.notes = notes == null || notes.length === 0 ? undefined : notes
+	}
+
 	return {
 		emptyInlineScriptModuleIds: Array.from(emptyInlineScriptModuleIds)
 	}