feat(ENHANCE-001): complete dynamic handles and execution pipeline

- Render dynamic input handles from model schema (GenerateImage/VideoNode)
- Update connection validation with getHandleType() helper
- Add dynamicInputs to getConnectedInputs() return value
- Pass dynamicInputs through generation pipeline (workflowStore -> API)
- Update generateWithFal/Replicate to use dynamic inputs
- Process large images in dynamicInputs to URLs for external providers
- Support prompt from dynamicInputs when top-level prompt is empty

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/app/api/generate/route.ts

@@ -19,6 +19,8 @@ const MODEL_MAP: Record<ModelType, string> = {
 interface MultiProviderGenerateRequest extends GenerateRequest {
   selectedModel?: SelectedModel;
   parameters?: Record<string, unknown>;
+  /** Dynamic inputs from schema-based connections (e.g., image_url, tail_image_url, prompt) */
+  dynamicInputs?: Record<string, string>;
 }
 
 /**
@@ -272,16 +274,20 @@ async function generateWithReplicate(
     };
   }
 
+  const hasDynamicInputs = input.dynamicInputs && Object.keys(input.dynamicInputs).length > 0;
+
   // Build input for the prediction
   const predictionInput: Record<string, unknown> = {
-    prompt: input.prompt,
     ...input.parameters,
   };
 
-  // Log parameters being passed
+  // Add dynamic inputs if provided (these come from schema-mapped connections)
-  if (input.parameters && Object.keys(input.parameters).length > 0) {
+  if (hasDynamicInputs) {
-    console.log(`[API:${requestId}] Custom parameters:`, JSON.stringify(input.parameters));
+    Object.assign(predictionInput, input.dynamicInputs);
-  }
+    console.log(`[API:${requestId}] Using dynamic inputs:`, Object.keys(input.dynamicInputs!).join(", "));
+  } else {
+    // Fallback to legacy behavior
+    predictionInput.prompt = input.prompt;
 
     // Add image input if provided (for img2img workflows)
     // Note: Different Replicate models use different parameter names
@@ -290,6 +296,12 @@ async function generateWithReplicate(
       predictionInput.image = input.images[0];
       console.log(`[API:${requestId}] Added image input to prediction (${input.images[0].substring(0, 50)}...)`);
     }
+  }
+
+  // Log parameters being passed
+  if (input.parameters && Object.keys(input.parameters).length > 0) {
+    console.log(`[API:${requestId}] Custom parameters:`, JSON.stringify(input.parameters));
+  }
 
   // Create a prediction
   console.log(`[API:${requestId}] Creating Replicate prediction...`);
@@ -474,20 +486,25 @@ async function generateWithFal(
   console.log(`[API:${requestId}]   - Model: ${input.model.id}`);
   console.log(`[API:${requestId}]   - Prompt length: ${input.prompt.length} chars`);
   console.log(`[API:${requestId}]   - Images count: ${input.images?.length || 0}`);
+  console.log(`[API:${requestId}]   - Dynamic inputs: ${input.dynamicInputs ? Object.keys(input.dynamicInputs).join(", ") : "none"}`);
   console.log(`[API:${requestId}]   - API key: ${apiKey ? "provided" : "not provided (using rate-limited access)"}`);
 
   const modelId = input.model.id;
+  const hasDynamicInputs = input.dynamicInputs && Object.keys(input.dynamicInputs).length > 0;
 
   // Build request body
+  // If we have dynamic inputs, they take precedence (they already contain prompt, image_url, etc.)
   const requestBody: Record<string, unknown> = {
-    prompt: input.prompt,
     ...input.parameters,
   };
 
-  // Log parameters being passed
+  // Add dynamic inputs if provided (these come from schema-mapped connections)
-  if (input.parameters && Object.keys(input.parameters).length > 0) {
+  if (hasDynamicInputs) {
-    console.log(`[API:${requestId}] Custom parameters:`, JSON.stringify(input.parameters));
+    Object.assign(requestBody, input.dynamicInputs);
-  }
+    console.log(`[API:${requestId}] Using dynamic inputs:`, Object.keys(input.dynamicInputs!).join(", "));
+  } else {
+    // Fallback to legacy behavior: use prompt and images array
+    requestBody.prompt = input.prompt;
 
     // Add image_url if provided (for img2img workflows)
     // fal.ai accepts both URLs and data URIs in this field
@@ -495,6 +512,12 @@ async function generateWithFal(
       requestBody.image_url = input.images[0];
       console.log(`[API:${requestId}] Added image_url to request (${input.images[0].substring(0, 50)}...)`);
     }
+  }
+
+  // Log parameters being passed
+  if (input.parameters && Object.keys(input.parameters).length > 0) {
+    console.log(`[API:${requestId}] Custom parameters:`, JSON.stringify(input.parameters));
+  }
 
   // Build headers
   const headers: Record<string, string> = {
@@ -639,9 +662,12 @@ export async function POST(request: NextRequest) {
       useGoogleSearch,
       selectedModel,
       parameters,
+      dynamicInputs,
     } = body;
 
-    if (!prompt) {
+    // Prompt is required unless provided via dynamicInputs
+    const hasPrompt = prompt || (dynamicInputs && dynamicInputs.prompt);
+    if (!hasPrompt) {
       console.error(`[API:${requestId}] Validation failed: missing prompt`);
       return NextResponse.json<GenerateResponse>(
         {
@@ -689,6 +715,31 @@ export async function POST(request: NextRequest) {
         }
       }
 
+      // Process dynamicInputs: convert large images in image-type inputs to URLs
+      const processedDynamicInputs: Record<string, string> | undefined = dynamicInputs
+        ? { ...dynamicInputs }
+        : undefined;
+
+      if (processedDynamicInputs) {
+        // Image input names that might contain base64 data
+        const imageInputNames = ["image", "image_url", "tail_image_url", "first_frame", "last_frame",
+          "start_image", "end_image", "reference_image", "init_image", "mask_image", "control_image"];
+
+        for (const key of Object.keys(processedDynamicInputs)) {
+          const value = processedDynamicInputs[key];
+          // Check if this is an image input with base64 data
+          if (imageInputNames.some(name => key.toLowerCase().includes(name.toLowerCase())) &&
+              value && value.startsWith("data:image")) {
+            if (shouldUseImageUrl(value)) {
+              const { url, id } = uploadImageForUrl(value, baseUrl);
+              uploadedImageIds.push(id);
+              processedDynamicInputs[key] = url;
+              console.log(`[API:${requestId}] Converted large dynamic input '${key}' to URL: ${url}`);
+            }
+          }
+        }
+      }
+
       try {
         // Build generation input
         const genInput: GenerationInput = {
@@ -699,9 +750,10 @@ export async function POST(request: NextRequest) {
             capabilities: ["text-to-image"],
             description: null,
           },
-          prompt,
+          prompt: prompt || "",
           images: processedImages,
           parameters,
+          dynamicInputs: processedDynamicInputs,
         };
 
         const result = await generateWithReplicate(requestId, replicateApiKey, genInput);
@@ -777,6 +829,31 @@ export async function POST(request: NextRequest) {
         }
       }
 
+      // Process dynamicInputs: convert large images in image-type inputs to URLs
+      const processedDynamicInputs: Record<string, string> | undefined = dynamicInputs
+        ? { ...dynamicInputs }
+        : undefined;
+
+      if (processedDynamicInputs) {
+        // Image input names that might contain base64 data
+        const imageInputNames = ["image_url", "tail_image_url", "first_frame", "last_frame",
+          "start_image", "end_image", "reference_image", "init_image", "mask_image", "control_image"];
+
+        for (const key of Object.keys(processedDynamicInputs)) {
+          const value = processedDynamicInputs[key];
+          // Check if this is an image input with base64 data
+          if (imageInputNames.some(name => key.toLowerCase().includes(name.toLowerCase())) &&
+              value && value.startsWith("data:image")) {
+            if (shouldUseImageUrl(value)) {
+              const { url, id } = uploadImageForUrl(value, baseUrl);
+              uploadedImageIds.push(id);
+              processedDynamicInputs[key] = url;
+              console.log(`[API:${requestId}] Converted large dynamic input '${key}' to URL: ${url}`);
+            }
+          }
+        }
+      }
+
       try {
         // Build generation input
         const genInput: GenerationInput = {
@@ -787,9 +864,10 @@ export async function POST(request: NextRequest) {
             capabilities: ["text-to-image"],
             description: null,
           },
-          prompt,
+          prompt: prompt || "",
           images: processedImages,
           parameters,
+          dynamicInputs: processedDynamicInputs,
         };
 
         const result = await generateWithFal(requestId, falApiKey, genInput);

src/components/WorkflowCanvas.tsx

@@ -57,14 +57,32 @@ const edgeTypes: EdgeTypes = {
 // Connection validation rules
 // - Image handles (green) can only connect to image handles
 // - Text handles (blue) can only connect to text handles
+// Helper to determine handle type from handle ID
+// For dynamic handles, we use naming convention: image inputs contain "image", text inputs are "prompt" or "negative_prompt"
+const getHandleType = (handleId: string | null | undefined): "image" | "text" | null => {
+  if (!handleId) return null;
+  // Standard handles
+  if (handleId === "image" || handleId === "text") return handleId;
+  // Dynamic handles - check naming patterns
+  if (handleId.includes("image") || handleId.includes("frame")) return "image";
+  if (handleId === "prompt" || handleId === "negative_prompt" || handleId.includes("prompt")) return "text";
+  return null;
+};
+
+// Connection validation: ensures type matching between source and target handles
+// - Image handles can connect to image handles
+// - Text handles can connect to text handles
 // - NanoBanana image input accepts multiple connections
 // - All other inputs accept only one connection
 const isValidConnection = (connection: Edge | Connection): boolean => {
   const sourceHandle = connection.sourceHandle;
   const targetHandle = connection.targetHandle;
 
+  const sourceType = getHandleType(sourceHandle);
+  const targetType = getHandleType(targetHandle);
+
   // Strict type matching: image <-> image, text <-> text
-  if (sourceHandle === "image" && targetHandle !== "image") {
+  if (sourceType === "image" && targetType !== "image") {
     logger.warn('connection.validation', 'Connection validation failed: type mismatch', {
       source: connection.source,
       target: connection.target,
@@ -74,7 +92,7 @@ const isValidConnection = (connection: Edge | Connection): boolean => {
     });
     return false;
   }
-  if (sourceHandle === "text" && targetHandle !== "text") {
+  if (sourceType === "text" && targetType !== "text") {
     logger.warn('connection.validation', 'Connection validation failed: type mismatch', {
       source: connection.source,
       target: connection.target,

src/components/nodes/GenerateImageNode.tsx

@@ -335,7 +335,37 @@ export function GenerateImageNode({ id, data, selected }: NodeProps<NanoBananaNo
       isExecuting={isRunning}
       hasError={nodeData.status === "error"}
     >
-      {/* Image input - accepts multiple connections */}
+      {/* Dynamic input handles based on model schema (external providers only) */}
+      {!isGeminiProvider && nodeData.inputSchema && nodeData.inputSchema.length > 0 ? (
+        // Render handles from schema
+        nodeData.inputSchema.map((input, index) => {
+          const total = nodeData.inputSchema!.length;
+          const topPercent = ((index + 1) / (total + 1)) * 100;
+          return (
+            <div key={input.name}>
+              <Handle
+                type="target"
+                position={Position.Left}
+                id={input.name}
+                style={{ top: `${topPercent}%` }}
+                data-handletype={input.type}
+                isConnectable={true}
+                title={input.description || input.label}
+              />
+              {/* Handle label */}
+              <div
+                className="absolute text-[8px] text-neutral-500 whitespace-nowrap pointer-events-none"
+                style={{ left: 12, top: `calc(${topPercent}% - 6px)` }}
+              >
+                {input.label}
+                {input.required && <span className="text-red-400">*</span>}
+              </div>
+            </div>
+          );
+        })
+      ) : (
+        // Default handles for Gemini or when no schema
+        <>
           <Handle
             type="target"
             position={Position.Left}
@@ -344,7 +374,6 @@ export function GenerateImageNode({ id, data, selected }: NodeProps<NanoBananaNo
             data-handletype="image"
             isConnectable={true}
           />
-      {/* Text input - single connection */}
           <Handle
             type="target"
             position={Position.Left}
@@ -352,6 +381,8 @@ export function GenerateImageNode({ id, data, selected }: NodeProps<NanoBananaNo
             style={{ top: "65%" }}
             data-handletype="text"
           />
+        </>
+      )}
       {/* Image output */}
       <Handle
         type="source"

src/components/nodes/GenerateVideoNode.tsx

@@ -170,7 +170,37 @@ export function GenerateVideoNode({ id, data, selected }: NodeProps<GenerateVide
       isExecuting={isRunning}
       hasError={nodeData.status === "error"}
     >
-      {/* Image input - accepts multiple connections */}
+      {/* Dynamic input handles based on model schema */}
+      {nodeData.inputSchema && nodeData.inputSchema.length > 0 ? (
+        // Render handles from schema
+        nodeData.inputSchema.map((input, index) => {
+          const total = nodeData.inputSchema!.length;
+          const topPercent = ((index + 1) / (total + 1)) * 100;
+          return (
+            <div key={input.name}>
+              <Handle
+                type="target"
+                position={Position.Left}
+                id={input.name}
+                style={{ top: `${topPercent}%` }}
+                data-handletype={input.type}
+                isConnectable={true}
+                title={input.description || input.label}
+              />
+              {/* Handle label */}
+              <div
+                className="absolute text-[8px] text-neutral-500 whitespace-nowrap pointer-events-none"
+                style={{ left: 12, top: `calc(${topPercent}% - 6px)` }}
+              >
+                {input.label}
+                {input.required && <span className="text-red-400">*</span>}
+              </div>
+            </div>
+          );
+        })
+      ) : (
+        // Default handles when no schema
+        <>
           <Handle
             type="target"
             position={Position.Left}
@@ -179,7 +209,6 @@ export function GenerateVideoNode({ id, data, selected }: NodeProps<GenerateVide
             data-handletype="image"
             isConnectable={true}
           />
-      {/* Text input - single connection */}
           <Handle
             type="target"
             position={Position.Left}
@@ -187,7 +216,9 @@ export function GenerateVideoNode({ id, data, selected }: NodeProps<GenerateVide
             style={{ top: "65%" }}
             data-handletype="text"
           />
-      {/* Video output - we use "image" handle type for now since the connection system expects image/text */}
+        </>
+      )}
+      {/* Video output */}
       <Handle
         type="source"
         position={Position.Right}

src/lib/providers/types.ts

@@ -84,6 +84,8 @@ export interface GenerationInput {
   images?: string[];
   /** Model-specific parameters (varies by provider/model) */
   parameters?: Record<string, unknown>;
+  /** Dynamic inputs mapped from schema (e.g., { "image_url": "data:...", "tail_image_url": "data:..." }) */
+  dynamicInputs?: Record<string, string>;
 }
 
 /**

src/store/workflowStore.ts

@@ -115,7 +115,7 @@ interface WorkflowStore {
 
   // Helpers
   getNodeById: (id: string) => WorkflowNode | undefined;
-  getConnectedInputs: (nodeId: string) => { images: string[]; text: string | null };
+  getConnectedInputs: (nodeId: string) => { images: string[]; text: string | null; dynamicInputs: Record<string, string> };
   validateWorkflow: () => { valid: boolean; errors: string[] };
 
   // Global Image History
@@ -816,6 +816,37 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
     const { edges, nodes } = get();
     const images: string[] = [];
     let text: string | null = null;
+    const dynamicInputs: Record<string, string> = {};
+
+    // Helper to determine if a handle ID is an image type
+    const isImageHandle = (handleId: string | null | undefined): boolean => {
+      if (!handleId) return false;
+      return handleId === "image" || handleId.includes("image") || handleId.includes("frame");
+    };
+
+    // Helper to determine if a handle ID is a text type
+    const isTextHandle = (handleId: string | null | undefined): boolean => {
+      if (!handleId) return false;
+      return handleId === "text" || handleId.includes("prompt");
+    };
+
+    // Helper to extract output from source node
+    const getSourceOutput = (sourceNode: WorkflowNode): { type: "image" | "text"; value: string | null } => {
+      if (sourceNode.type === "imageInput") {
+        return { type: "image", value: (sourceNode.data as ImageInputNodeData).image };
+      } else if (sourceNode.type === "annotation") {
+        return { type: "image", value: (sourceNode.data as AnnotationNodeData).outputImage };
+      } else if (sourceNode.type === "nanoBanana") {
+        return { type: "image", value: (sourceNode.data as NanoBananaNodeData).outputImage };
+      } else if (sourceNode.type === "generateVideo") {
+        return { type: "image", value: (sourceNode.data as GenerateVideoNodeData).outputVideo };
+      } else if (sourceNode.type === "prompt") {
+        return { type: "text", value: (sourceNode.data as PromptNodeData).prompt };
+      } else if (sourceNode.type === "llmGenerate") {
+        return { type: "text", value: (sourceNode.data as LLMGenerateNodeData).outputText };
+      }
+      return { type: "image", value: null };
+    };
 
     edges
       .filter((edge) => edge.target === nodeId)
@@ -824,35 +855,24 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
         if (!sourceNode) return;
 
         const handleId = edge.targetHandle;
+        const { value } = getSourceOutput(sourceNode);
 
-        if (handleId === "image" || !handleId) {
+        if (!value) return;
-          // Get image from source node - collect all connected images
-          if (sourceNode.type === "imageInput") {
-            const sourceImage = (sourceNode.data as ImageInputNodeData).image;
-            if (sourceImage) images.push(sourceImage);
-          } else if (sourceNode.type === "annotation") {
-            const sourceImage = (sourceNode.data as AnnotationNodeData).outputImage;
-            if (sourceImage) images.push(sourceImage);
-          } else if (sourceNode.type === "nanoBanana") {
-            const sourceImage = (sourceNode.data as NanoBananaNodeData).outputImage;
-            if (sourceImage) images.push(sourceImage);
-          } else if (sourceNode.type === "generateVideo") {
-            // Video output can be used as input to downstream nodes
-            const sourceVideo = (sourceNode.data as GenerateVideoNodeData).outputVideo;
-            if (sourceVideo) images.push(sourceVideo);
-          }
-        }
 
-        if (handleId === "text") {
+        // Store in dynamic inputs if handle ID is specific (not just "image" or "text")
-          if (sourceNode.type === "prompt") {
+        if (handleId && handleId !== "image" && handleId !== "text") {
-            text = (sourceNode.data as PromptNodeData).prompt;
+          dynamicInputs[handleId] = value;
-          } else if (sourceNode.type === "llmGenerate") {
-            text = (sourceNode.data as LLMGenerateNodeData).outputText;
         }
+
+        // Also populate legacy arrays for backward compatibility
+        if (isImageHandle(handleId) || !handleId) {
+          images.push(value);
+        } else if (isTextHandle(handleId)) {
+          text = value;
         }
       });
 
-    return { images, text };
+    return { images, text, dynamicInputs };
   },
 
   validateWorkflow: () => {
@@ -1041,9 +1061,11 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
             break;
 
           case "nanoBanana": {
-            const { images, text } = getConnectedInputs(node.id);
+            const { images, text, dynamicInputs } = getConnectedInputs(node.id);
 
-            if (!text) {
+            // For dynamic inputs, check if we have at least a prompt
+            const promptText = text || dynamicInputs.prompt || null;
+            if (!promptText) {
               logger.error('node.error', 'nanoBanana node missing text input', {
                 nodeId: node.id,
               });
@@ -1058,7 +1080,7 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
 
             updateNodeData(node.id, {
               inputImages: images,
-              inputPrompt: text,
+              inputPrompt: promptText,
               status: "loading",
               error: null,
             });
@@ -1069,13 +1091,14 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
 
               const requestPayload = {
                 images,
-                prompt: text,
+                prompt: promptText,
                 aspectRatio: nodeData.aspectRatio,
                 resolution: nodeData.resolution,
                 model: nodeData.model,
                 useGoogleSearch: nodeData.useGoogleSearch,
                 selectedModel: nodeData.selectedModel,
                 parameters: nodeData.parameters,
+                dynamicInputs,  // Pass dynamic inputs for schema-mapped connections
               };
 
               // Build headers with API keys for external providers
@@ -1102,7 +1125,7 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
                 aspectRatio: nodeData.aspectRatio,
                 resolution: nodeData.resolution,
                 imageCount: images.length,
-                prompt: text,
+                prompt: promptText,
               });
 
               const response = await fetch("/api/generate", {
@@ -1148,7 +1171,7 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
                 get().addToGlobalHistory({
                   image: result.image,
                   timestamp,
-                  prompt: text,
+                  prompt: promptText,
                   aspectRatio: nodeData.aspectRatio,
                   model: nodeData.model,
                 });
@@ -1157,7 +1180,7 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
                 const newHistoryItem = {
                   id: imageId,
                   timestamp,
-                  prompt: text,
+                  prompt: promptText,
                   aspectRatio: nodeData.aspectRatio,
                   model: nodeData.model,
                 };
@@ -1237,15 +1260,17 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
           }
 
           case "generateVideo": {
-            const { images, text } = getConnectedInputs(node.id);
+            const { images, text, dynamicInputs } = getConnectedInputs(node.id);
 
-            if (!text) {
+            // For dynamic inputs, check if we have at least a prompt
-              logger.error('node.error', 'generateVideo node missing text input', {
+            const hasPrompt = text || dynamicInputs.prompt || dynamicInputs.negative_prompt;
+            if (!hasPrompt && images.length === 0) {
+              logger.error('node.error', 'generateVideo node missing inputs', {
                 nodeId: node.id,
               });
               updateNodeData(node.id, {
                 status: "error",
-                error: "Missing text input",
+                error: "Missing required inputs",
               });
               set({ isRunning: false, currentNodeId: null });
               await logger.endSession();
@@ -1282,6 +1307,7 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
                 prompt: text,
                 selectedModel: nodeData.selectedModel,
                 parameters: nodeData.parameters,
+                dynamicInputs,  // Pass dynamic inputs for schema-mapped connections
               };
 
               // Build headers with API keys for external providers