diff --git a/easyflow-modules/easyflow-module-ai/src/main/java/tech/easyflow/ai/easyagentsflow/service/WorkflowCheckService.java b/easyflow-modules/easyflow-module-ai/src/main/java/tech/easyflow/ai/easyagentsflow/service/WorkflowCheckService.java
index 700f891c..96489d23 100644
--- a/easyflow-modules/easyflow-module-ai/src/main/java/tech/easyflow/ai/easyagentsflow/service/WorkflowCheckService.java
+++ b/easyflow-modules/easyflow-module-ai/src/main/java/tech/easyflow/ai/easyagentsflow/service/WorkflowCheckService.java
@@ -832,11 +832,36 @@ public class WorkflowCheckService {
                 continue;
             }
             if (workflowDatacenterContentService.isLlmNode(node.type)) {
+                checkLlmUserPrompt(node, issues, issueKeys);
                 checkLlmQueryContext(node, parsed, issues, issueKeys);
             }
         }
     }
 
+    /**
+     * 校验大模型节点的用户提示词，避免空提示词进入运行时解析。
+     *
+     * @param node 大模型节点
+     * @param issues 问题列表
+     * @param issueKeys 问题去重键
+     */
+    private void checkLlmUserPrompt(
+            NodeView node,
+            List<WorkflowCheckIssue> issues,
+            Set<String> issueKeys) {
+        String userPrompt = node.data == null ? null : node.data.getString("userPrompt");
+        if (!StringUtils.hasText(userPrompt)) {
+            addIssue(
+                    issues,
+                    issueKeys,
+                    "LLM_USER_PROMPT_EMPTY",
+                    "大模型节点的用户提示词不能为空",
+                    node.id,
+                    null,
+                    node.name);
+        }
+    }
+
     private void checkMakeFileNode(NodeView node,
                                    List<WorkflowCheckIssue> issues,
                                    Set<String> issueKeys) {
diff --git a/easyflow-modules/easyflow-module-ai/src/test/java/tech/easyflow/ai/easyagentsflow/service/WorkflowCheckServiceTest.java b/easyflow-modules/easyflow-module-ai/src/test/java/tech/easyflow/ai/easyagentsflow/service/WorkflowCheckServiceTest.java
index 40eefd45..2be7f0ff 100644
--- a/easyflow-modules/easyflow-module-ai/src/test/java/tech/easyflow/ai/easyagentsflow/service/WorkflowCheckServiceTest.java
+++ b/easyflow-modules/easyflow-module-ai/src/test/java/tech/easyflow/ai/easyagentsflow/service/WorkflowCheckServiceTest.java
@@ -436,6 +436,41 @@ public class WorkflowCheckServiceTest {
         assertHasCode(result, "SEARCH_DATASET_INVALID");
     }
 
+    /**
+     * 验证保存阶段拒绝空白的大模型用户提示词。
+     */
+    @Test
+    public void testSaveShouldBlockBlankLlmUserPrompt() throws Exception {
+        WorkflowCheckService service = newService(new HashMap<>());
+        JSONObject llmData = data("大模型");
+        llmData.put("userPrompt", "   ");
+        String content = workflowJson(
+                array(node("llm-1", "llmNode", null, llmData)),
+                new JSONArray()
+        );
+
+        WorkflowCheckResult result = service.checkContent(content, WorkflowCheckStage.SAVE, null);
+        Assert.assertFalse(result.isPassed());
+        assertHasCode(result, "LLM_USER_PROMPT_EMPTY");
+    }
+
+    /**
+     * 验证保存阶段接受有效的大模型用户提示词。
+     */
+    @Test
+    public void testSaveShouldPassNonBlankLlmUserPrompt() throws Exception {
+        WorkflowCheckService service = newService(new HashMap<>());
+        JSONObject llmData = data("大模型");
+        llmData.put("userPrompt", "{{start-1.user_input}}");
+        String content = workflowJson(
+                array(node("llm-1", "llmNode", null, llmData)),
+                new JSONArray()
+        );
+
+        WorkflowCheckResult result = service.checkContent(content, WorkflowCheckStage.SAVE, null);
+        Assert.assertTrue(result.isPassed());
+    }
+
     @Test
     public void testPreExecuteShouldBlockMissingStartOrEnd() throws Exception {
         WorkflowCheckService service = newService(new HashMap<>());
@@ -453,6 +488,34 @@ public class WorkflowCheckServiceTest {
         assertHasCode(result, "END_NODE_MISSING");
     }
 
+    /**
+     * 验证执行前校验拒绝空的大模型用户提示词。
+     */
+    @Test
+    public void testPreExecuteShouldBlockEmptyLlmUserPrompt() throws Exception {
+        WorkflowCheckService service = newService(new HashMap<>());
+        JSONObject llmData = data("大模型");
+        llmData.put("userPrompt", "");
+        String content = workflowJson(
+                array(
+                        node("s1", "startNode", null, data("开始")),
+                        node("llm-1", "llmNode", null, llmData),
+                        node("e1", "endNode", null, data("结束"))
+                ),
+                array(
+                        edge("edge-1", "s1", "llm-1"),
+                        edge("edge-2", "llm-1", "e1")
+                )
+        );
+
+        WorkflowCheckResult result = service.checkContent(
+                content,
+                WorkflowCheckStage.PRE_EXECUTE,
+                BigInteger.ONE);
+        Assert.assertFalse(result.isPassed());
+        assertHasCode(result, "LLM_USER_PROMPT_EMPTY");
+    }
+
     @Test
     public void testPreExecuteShouldPassForSourceOnlySearchDatasetNode() throws Exception {
         WorkflowCheckService service = newService(new HashMap<>());
diff --git a/easyflow-ui-admin/packages/tinyflow-ui/src/components/core/DefinedParameterItem.svelte b/easyflow-ui-admin/packages/tinyflow-ui/src/components/core/DefinedParameterItem.svelte
index 0da514e5..68b643ba 100644
--- a/easyflow-ui-admin/packages/tinyflow-ui/src/components/core/DefinedParameterItem.svelte
+++ b/easyflow-ui-admin/packages/tinyflow-ui/src/components/core/DefinedParameterItem.svelte
@@ -52,9 +52,10 @@
         return param.formType ? [param.formType] : [];
     });
     let parameterNameDraft = $state<string | null>(null);
+    let systemLabelDraft = $state<string | null>(null);
     let displayParamName = $derived.by(() => {
         if (isSystemStartParam) {
-            return '用户问题';
+            return systemLabelDraft ?? trimString(param.formLabel);
         }
         return parameterNameDraft ?? param.name;
     });
@@ -76,6 +77,8 @@
 
     const applyStartFieldPatch = (fieldKey: string, patch: Record<string, any>) => {
         const currentFieldId = trimString(param.id);
+        const shouldSyncReferences = Object.prototype.hasOwnProperty.call(patch, 'key')
+            || Object.prototype.hasOwnProperty.call(patch, 'label');
         store.updateNodes((nodes) => {
             const edges = store.getEdges();
             let nextFieldKey = fieldKey;
@@ -98,6 +101,9 @@
                     }
                 };
             });
+            if (!shouldSyncReferences) {
+                return nextNodes;
+            }
             return renameStartFieldReferencesInNodes(
                 nextNodes,
                 edges,
@@ -172,11 +178,11 @@
     const updateName = (event: Event) => {
         const input = event.target as HTMLInputElement;
         const newValue = input.value;
+        parameterNameDraft = newValue;
         if (isStartNodeInputParam) {
             const normalizedValue = trimString(newValue);
             if (!normalizedValue) {
                 parameterNameError = '参数名不能为空';
-                parameterNameDraft = newValue;
                 return;
             }
             if (!isStartFormFieldKeyAvailable(
@@ -185,13 +191,66 @@
                 normalizedValue
             )) {
                 parameterNameError = '参数名已存在';
-                parameterNameDraft = newValue;
                 return;
             }
         }
+        parameterNameError = '';
+    };
+
+    const updateVisibleName = (event: Event) => {
+        if (isSystemStartParam) {
+            systemLabelDraft = (event.target as HTMLInputElement).value;
+            return;
+        }
+        updateName(event);
+    };
+
+    const commitName = () => {
+        if (parameterNameDraft === null) {
+            return;
+        }
+        const draftValue = parameterNameDraft;
+        if (isStartNodeInputParam) {
+            const normalizedValue = trimString(draftValue);
+            if (!normalizedValue) {
+                parameterNameError = '参数名不能为空';
+                return;
+            }
+            if (!isStartFormFieldKeyAvailable(
+                node?.current?.data as Record<string, any>,
+                param.name || '',
+                normalizedValue
+            )) {
+                parameterNameError = '参数名已存在';
+                return;
+            }
+            parameterNameDraft = null;
+            parameterNameError = '';
+            if (normalizedValue !== trimString(param.name)) {
+                updateParameter('name', normalizedValue);
+            }
+            return;
+        }
         parameterNameDraft = null;
         parameterNameError = '';
-        updateParameter('name', newValue);
+        if (draftValue !== (param.name || '')) {
+            updateParameter('name', draftValue);
+        }
+    };
+
+    const commitVisibleName = () => {
+        if (!isSystemStartParam) {
+            commitName();
+            return;
+        }
+        if (systemLabelDraft === null) {
+            return;
+        }
+        const nextLabel = trimString(systemLabelDraft);
+        systemLabelDraft = null;
+        if (nextLabel !== trimString(param.formLabel)) {
+            updateParameter('formLabel', nextLabel);
+        }
     };
 
     const updateRequired = (event: Event) => {
@@ -236,11 +295,13 @@
 
 
 <div class="input-item input-item-name">
-    <Input style="width: 100%;" value={displayParamName} placeholder="请输入参数名称"
-           disabled={param.nameDisabled === true}
+    <Input style="width: 100%;" value={displayParamName}
+           placeholder={isSystemStartParam ? '用户问题' : '请输入参数名称'}
+           disabled={isSystemStartParam ? false : param.nameDisabled === true}
            aria-invalid={parameterNameError ? 'true' : undefined}
            aria-describedby={parameterNameError ? parameterNameErrorId : undefined}
-           oninput={updateName} />
+           oninput={updateVisibleName}
+           onchange={commitVisibleName} />
     {#if parameterNameError}
         <div id={parameterNameErrorId} class="input-error" role="alert">
             {parameterNameError}
@@ -296,7 +357,7 @@
                     数据标题：
                     <Textarea rows={1} style="width: 100%;" onchange={(event)=>{
                         updateParamByEvent('formLabel', event)
-                    }} value={param.formLabel} />
+                    }} value={param.formLabel} placeholder={isSystemStartParam ? '用户问题' : undefined} />
                 </div>
 
                 <div class="input-more-item">
diff --git a/easyflow-ui-admin/packages/tinyflow-ui/src/utils/workflowNodeFields.test.ts b/easyflow-ui-admin/packages/tinyflow-ui/src/utils/workflowNodeFields.test.ts
index 45d84296..5837f261 100644
--- a/easyflow-ui-admin/packages/tinyflow-ui/src/utils/workflowNodeFields.test.ts
+++ b/easyflow-ui-admin/packages/tinyflow-ui/src/utils/workflowNodeFields.test.ts
@@ -34,18 +34,57 @@ describe('workflow node fields', () => {
     expect(parameters[0]?.name).toBe('user_input');
     expect(parameters[0]?.systemReserved).toBe(true);
     expect(parameters[0]?.required).toBe(true);
+    expect(parameters[0]?.formLabel).toBe('');
+    expect(parameters[0]?.displayName).toBe('流程开始 > 用户问题');
     expect(initial.nodes[0]?.data?.startFormMeta).toMatchObject({
       title: '开始问答',
       submitText: '开始',
     });
     expect(initial.nodes[0]?.data?.startFormSchema?.[0]).toMatchObject({
       key: 'user_input',
+      label: '',
       type: 'textarea',
       systemReserved: true,
       required: true,
     });
   });
 
+  it('preserves an empty system start title for the default placeholder', () => {
+    const initial = createInitialWorkflowData();
+    const startData = initial.nodes[0]?.data as Record<string, any>;
+    const customized = updateStartFormField(startData, 'user_input', {
+      label: '反洗钱',
+    });
+    const cleared = updateStartFormField(customized, 'user_input', {
+      label: '',
+    });
+
+    expect(customized.startFormSchema?.[0]?.label).toBe('反洗钱');
+    expect(cleared.startFormSchema?.[0]?.label).toBe('');
+    expect((cleared.parameters as any[])?.[0]?.formLabel).toBe('');
+    expect((cleared.parameters as any[])?.[0]?.displayName).toBe(
+      '流程开始 > 用户问题',
+    );
+  });
+
+  it('preserves an explicitly entered default or prefixed system title', () => {
+    const initial = createInitialWorkflowData();
+    const startData = initial.nodes[0]?.data as Record<string, any>;
+    const defaultTitle = updateStartFormField(startData, 'user_input', {
+      label: '用户问题',
+    });
+    const prefixedTitle = updateStartFormField(startData, 'user_input', {
+      label: '用户问题说明',
+    });
+
+    expect(defaultTitle.startFormSchema?.[0]?.label).toBe('用户问题');
+    expect((defaultTitle.parameters as any[])?.[0]?.formLabel).toBe('用户问题');
+    expect(prefixedTitle.startFormSchema?.[0]?.label).toBe('用户问题说明');
+    expect((prefixedTitle.parameters as any[])?.[0]?.formLabel).toBe(
+      '用户问题说明',
+    );
+  });
+
   it('appends custom start form field into schema source of truth', () => {
     const initial = createInitialWorkflowData();
     const startNode = initial.nodes[0]!;
@@ -326,6 +365,129 @@ describe('workflow node fields', () => {
     });
   });
 
+  it('refreshes downstream reference labels when the system title changes', () => {
+    const initial = createInitialWorkflowData();
+    const customStartData = updateStartFormField(
+      initial.nodes[0]?.data as Record<string, any>,
+      'user_input',
+      { label: '反洗钱' },
+    );
+    const clearedStartData = updateStartFormField(
+      customStartData,
+      'user_input',
+      { label: '' },
+    );
+    const startNode: Node = {
+      id: 'start_1',
+      type: 'startNode',
+      position: { x: 0, y: 0 },
+      data: {
+        title: '开始节点',
+        ...clearedStartData,
+      },
+    };
+    const llmNode: Node = {
+      id: 'llm_1',
+      type: 'llmNode',
+      position: { x: 120, y: 0 },
+      data: {
+        title: '大模型',
+        userPrompt: '',
+        parameters: [
+          {
+            id: 'param_1',
+            name: 'start_1.user_input',
+            ref: 'start_1.user_input',
+            refType: 'ref',
+            autoManaged: true,
+            formLabel: '开始节点 > 反洗钱',
+            displayName: '开始节点 > 反洗钱',
+          },
+        ],
+      },
+    };
+    const endNode: Node = {
+      id: 'end_1',
+      type: 'endNode',
+      position: { x: 240, y: 0 },
+      data: {
+        title: '结束节点',
+        parameters: [
+          {
+            id: 'param_2',
+            name: 'start_1.user_input',
+            ref: 'start_1.user_input',
+            refType: 'ref',
+            formLabel: '开始节点 > 反洗钱',
+            displayName: '开始节点 > 反洗钱',
+          },
+        ],
+      },
+    };
+    const edges: Edge[] = [
+      { id: 'edge_1', source: 'start_1', target: 'llm_1' } as Edge,
+      { id: 'edge_2', source: 'llm_1', target: 'end_1' } as Edge,
+    ];
+
+    const nextNodes = renameStartFieldReferencesInNodes(
+      [startNode, llmNode, endNode],
+      edges,
+      'start_1',
+      'user_input',
+      'user_input',
+    );
+    const nextLlmNode = nextNodes.find((node) => node.id === 'llm_1')!;
+    const nextParameter = (nextLlmNode.data?.parameters as any[])?.[0];
+    const nextEndParameter = (
+      nextNodes.find((node) => node.id === 'end_1')?.data?.parameters as any[]
+    )?.[0];
+
+    expect(nextLlmNode.data?.userPrompt).toBe('');
+    expect(nextParameter?.name).toBe('start_1.user_input');
+    expect(nextParameter?.ref).toBe('start_1.user_input');
+    expect(nextParameter?.displayName).toBe('开始节点 > 用户问题');
+    expect(nextParameter?.formLabel).toBe('开始节点 > 用户问题');
+    expect(nextEndParameter?.displayName).toBe('开始节点 > 用户问题');
+    expect(nextEndParameter?.formLabel).toBe('开始节点 > 用户问题');
+    expect((nextLlmNode.data as any)?.[FIELD_BINDING_META_KEY]).toBeUndefined();
+  });
+
+  it('preserves node identities when a title sync has nothing to update', () => {
+    const initial = createInitialWorkflowData();
+    const startNode: Node = {
+      ...initial.nodes[0]!,
+      id: 'start_1',
+    };
+    const untouchedNode: Node = {
+      id: 'code_1',
+      type: 'codeNode',
+      position: { x: 120, y: 0 },
+      data: {
+        title: '代码节点',
+        parameters: [
+          {
+            id: 'param_1',
+            name: 'manual_value',
+            displayName: '手工参数',
+          },
+        ],
+      },
+    };
+    const nodes = [startNode, untouchedNode];
+
+    const nextNodes = renameStartFieldReferencesInNodes(
+      nodes,
+      [],
+      'start_1',
+      'user_input',
+      'user_input',
+    );
+
+    expect(nextNodes).toBe(nodes);
+    expect(nextNodes[0]).toBe(startNode);
+    expect(nextNodes[1]).toBe(untouchedNode);
+  });
+
   it('preserves resource content type independently from input type', () => {
     for (const contentType of ['image', 'video', 'audio', 'other'] as const) {
       const key = `preview_${contentType}`;
diff --git a/easyflow-ui-admin/packages/tinyflow-ui/src/utils/workflowNodeFields.ts b/easyflow-ui-admin/packages/tinyflow-ui/src/utils/workflowNodeFields.ts
index 25ee2d6d..0a33bff2 100644
--- a/easyflow-ui-admin/packages/tinyflow-ui/src/utils/workflowNodeFields.ts
+++ b/easyflow-ui-admin/packages/tinyflow-ui/src/utils/workflowNodeFields.ts
@@ -184,6 +184,9 @@ function getNodeTitle(node?: Node | null) {
 }
 
 function getParameterLabel(parameter?: Parameter | null) {
+  if (isSystemStartParameter(parameter)) {
+    return trimString(parameter?.formLabel) || SYSTEM_START_PARAM_LABEL;
+  }
   return (
     asString(parameter?.formLabel).trim() ||
     asString(parameter?.displayName).trim() ||
@@ -415,6 +418,14 @@ function normalizeSystemStartFormType(value: unknown): 'input' | 'textarea' {
   return trimString(value) === 'input' ? 'input' : 'textarea';
 }
 
+function normalizeSystemStartFormLabel(value: unknown) {
+  return trimString(value);
+}
+
+function getSystemStartDisplayLabel(value: unknown) {
+  return normalizeSystemStartFormLabel(value) || SYSTEM_START_PARAM_LABEL;
+}
+
 function normalizeStartFormFieldUiType(
   value: unknown,
   fallback: StartFormFieldType = 'text',
@@ -519,8 +530,8 @@ export function normalizeStartFormMeta(
 function normalizeSystemStartParameter(
   parameter?: Parameter | null,
 ): Parameter {
-  const fallbackLabel = SYSTEM_START_PARAM_LABEL;
-  const formLabel = trimString(parameter?.formLabel) || fallbackLabel;
+  const formLabel = normalizeSystemStartFormLabel(parameter?.formLabel);
+  const displayLabel = getSystemStartDisplayLabel(formLabel);
   const formType = normalizeSystemStartFormType(parameter?.formType);
   return ensureParameterId({
     ...cloneParameter(parameter || {}),
@@ -534,7 +545,7 @@ function normalizeSystemStartParameter(
     formDescription: asString(parameter?.formDescription),
     formPlaceholder: trimString(parameter?.formPlaceholder) || '请输入用户问题',
     defaultValue: asString(parameter?.defaultValue),
-    displayName: `流程开始 > ${formLabel}`,
+    displayName: `流程开始 > ${displayLabel}`,
     nameDisabled: true,
     dataTypeDisabled: true,
     deleteDisabled: true,
@@ -637,11 +648,18 @@ function normalizeStartFormField(
   const options = isOptionFieldType(type)
     ? ensureStringArray(field?.options || existingParameter?.enums)
     : [];
-  const requestedLabel =
-    trimString(field?.label) ||
-    trimString(existingParameter?.formLabel) ||
-    trimString(existingParameter?.displayName) ||
-    key;
+  const hasFieldLabel = Object.prototype.hasOwnProperty.call(
+    field || {},
+    'label',
+  );
+  const requestedLabel = isSystemField
+    ? normalizeSystemStartFormLabel(
+        hasFieldLabel ? field?.label : existingParameter?.formLabel,
+      )
+    : trimString(field?.label) ||
+      trimString(existingParameter?.formLabel) ||
+      trimString(existingParameter?.displayName) ||
+      key;
   const label =
     !isSystemField &&
     isDefaultStartFormFieldLabel(requestedLabel) &&
@@ -796,8 +814,7 @@ export function normalizeStartFormSchema(
         {
           id: trimString(systemParameter?.id),
           key: SYSTEM_START_PARAM_NAME,
-          label:
-            trimString(systemParameter?.formLabel) || SYSTEM_START_PARAM_LABEL,
+          label: normalizeSystemStartFormLabel(systemParameter?.formLabel),
           type:
             normalizeSystemStartFormType(systemParameter?.formType) === 'input'
               ? 'text'
@@ -933,6 +950,7 @@ export function updateStartFormField(
       !trimString(patch.label) &&
       patch.type != null &&
       isDefaultStartFormFieldLabel(field.label);
+    const hasLabelPatch = Object.prototype.hasOwnProperty.call(patch, 'label');
     return {
       ...field,
       ...patch,
@@ -947,10 +965,12 @@ export function updateStartFormField(
             )
           : field.key),
       label:
-        trimString(patch.label) ||
-        (shouldAutoRenameLabel
-          ? getDefaultStartFormFieldLabel(nextType)
-          : field.label),
+        field.systemReserved && hasLabelPatch
+          ? normalizeSystemStartFormLabel(patch.label)
+          : trimString(patch.label) ||
+            (shouldAutoRenameLabel
+              ? getDefaultStartFormFieldLabel(nextType)
+              : field.label),
       type: nextType,
     };
   });
@@ -1450,28 +1470,115 @@ function replaceStartFieldReferenceValue(
 
 export function collectDownstreamNodeIds(rootNodeId: string, edges: Edge[]) {
   const nodeIds = new Set<string>();
+  const adjacency = new Map<string, string[]>();
+  for (const edge of edges) {
+    if (!edge.source || !edge.target || edge.sourceHandle === 'loop_handle') {
+      continue;
+    }
+    const targets = adjacency.get(edge.source);
+    if (targets) {
+      targets.push(edge.target);
+    } else {
+      adjacency.set(edge.source, [edge.target]);
+    }
+  }
 
-  const visit = (nodeId: string) => {
+  const pendingNodeIds = [rootNodeId];
+  while (pendingNodeIds.length > 0) {
+    const nodeId = pendingNodeIds.pop();
     if (!nodeId || nodeIds.has(nodeId)) {
-      return;
+      continue;
     }
     nodeIds.add(nodeId);
-    edges
-      .filter(
-        (edge) => edge.source === nodeId && edge.sourceHandle !== 'loop_handle',
-      )
-      .forEach((edge) => {
-        if (edge.target) {
-          visit(edge.target);
-        }
-      });
-  };
+    const targets = adjacency.get(nodeId) || [];
+    for (let index = targets.length - 1; index >= 0; index -= 1) {
+      pendingNodeIds.push(targets[index]!);
+    }
+  }
 
-  visit(rootNodeId);
   nodeIds.delete(rootNodeId);
   return Array.from(nodeIds);
 }
 
+function syncReferenceParameterLabels(
+  parameters: Parameter[],
+  refPath: string,
+  displayName: string,
+): Parameter[] {
+  let changed = false;
+  const nextParameters = parameters.map((parameter) => {
+    const currentChildren = Array.isArray(parameter.children)
+      ? parameter.children
+      : [];
+    const nextChildren = currentChildren.length
+      ? syncReferenceParameterLabels(currentChildren, refPath, displayName)
+      : currentChildren;
+    const matchesReference =
+      (parameter.autoManaged === true || parameter.refType === 'ref') &&
+      (trimString(parameter.name) === refPath ||
+        trimString(parameter.ref) === refPath);
+    const labelChanged =
+      matchesReference &&
+      (parameter.displayName !== displayName ||
+        parameter.formLabel !== displayName);
+    const childrenChanged = nextChildren !== currentChildren;
+    if (!labelChanged && !childrenChanged) {
+      return parameter;
+    }
+    changed = true;
+    return {
+      ...parameter,
+      ...(labelChanged ? { displayName, formLabel: displayName } : {}),
+      ...(childrenChanged ? { children: nextChildren } : {}),
+    };
+  });
+  return changed ? nextParameters : parameters;
+}
+
+function syncStartFieldReferenceLabelsInNodes(
+  nodes: Node[],
+  startNodeId: string,
+  fieldKey: string,
+) {
+  const startNode = nodes.find((node) => node.id === startNodeId);
+  const startParameters = Array.isArray(startNode?.data?.parameters)
+    ? (startNode.data.parameters as Parameter[])
+    : [];
+  const sourceParameter = findParameterByName(startParameters, fieldKey);
+  if (!startNode || !sourceParameter) {
+    return nodes;
+  }
+
+  const refPath = `${startNodeId}.${fieldKey}`;
+  const displayName = `${getNodeTitle(startNode)} > ${getReferenceParameterLabel(sourceParameter)}`;
+  let changed = false;
+  const nextNodes = nodes.map((node) => {
+    const parameters = Array.isArray(node.data?.parameters)
+      ? (node.data.parameters as Parameter[])
+      : [];
+    if (parameters.length === 0) {
+      return node;
+    }
+    const nextParameters = syncReferenceParameterLabels(
+      parameters,
+      refPath,
+      displayName,
+    );
+    if (nextParameters === parameters) {
+      return node;
+    }
+    changed = true;
+    return {
+      ...node,
+      data: {
+        ...((node.data || {}) as Record<string, any>),
+        parameters: nextParameters,
+      },
+    };
+  });
+  return changed ? nextNodes : nodes;
+}
+
 export function renameStartFieldReferencesInNodes(
   nodes: Node[],
   edges: Edge[],
@@ -1482,35 +1589,41 @@ export function renameStartFieldReferencesInNodes(
   const normalizedStartNodeId = trimString(startNodeId);
   const normalizedCurrentKey = trimString(currentKey);
   const normalizedNextKey = trimString(nextKey);
-  if (
-    !normalizedStartNodeId ||
-    !normalizedCurrentKey ||
-    !normalizedNextKey ||
-    normalizedCurrentKey === normalizedNextKey
-  ) {
+  if (!normalizedStartNodeId || !normalizedCurrentKey || !normalizedNextKey) {
     return nodes;
   }
 
   const oldRefPath = `${normalizedStartNodeId}.${normalizedCurrentKey}`;
   const newRefPath = `${normalizedStartNodeId}.${normalizedNextKey}`;
 
-  const nextNodes: Node[] = nodes.map((node) => {
-    if (node.id === normalizedStartNodeId) {
-      return node;
-    }
-    const nextData = replaceStartFieldReferenceValue(
-      node.data,
-      oldRefPath,
-      newRefPath,
-    ) as Record<string, any> | undefined;
-    if (nextData === node.data) {
-      return node;
-    }
-    return {
-      ...node,
-      data: nextData ?? {},
-    };
-  });
+  const keyChanged = normalizedCurrentKey !== normalizedNextKey;
+  const renamedNodes: Node[] = keyChanged
+    ? nodes.map((node) => {
+        if (node.id === normalizedStartNodeId) {
+          return node;
+        }
+        const nextData = replaceStartFieldReferenceValue(
+          node.data,
+          oldRefPath,
+          newRefPath,
+        ) as Record<string, any> | undefined;
+        if (nextData === node.data) {
+          return node;
+        }
+        return {
+          ...node,
+          data: nextData ?? {},
+        };
+      })
+    : nodes;
+  const nextNodes = syncStartFieldReferenceLabelsInNodes(
+    renamedNodes,
+    normalizedStartNodeId,
+    normalizedNextKey,
+  );
+  if (!keyChanged) {
+    return nextNodes;
+  }
 
   const affectedNodeIds = collectDownstreamNodeIds(
     normalizedStartNodeId,