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+# Roadmap: Node Banana Multi-Provider Support
+
+## Overview
+
+Transform Node Banana from a Gemini-only image generator into a multi-provider platform supporting Replicate and fal.ai. The journey builds provider infrastructure first, then adds dynamic model discovery, refactors the generate node for flexibility, creates a searchable model browser, adds local image serving for URL-based providers, and finishes with video support and polish.
+
+## Domain Expertise
+
+None
+
+## Milestones
+
+- ✅ **v1.0 Multi-Provider Support** - Phases 1-6 (shipped 2026-01-11)
+- ✅ **v1.1 Improvements** - Phases 7-14 (shipped 2026-01-12)
+- ✅ **v1.2 Improvements** - Phases 15-24 (shipped 2026-01-17)
+- ✅ **v1.3 Improvements** - Phases 25-30 (shipped 2026-01-24)
+- 🚧 **v1.4 Features** - Phases 31-35 (in progress)
+- 📋 **v1.5 Store Refactoring** - Phases 36-39 (planned)
+
+## Phases
+
+**Phase Numbering:**
+- Integer phases (1, 2, 3): Planned milestone work
+- Decimal phases (2.1, 2.2): Urgent insertions (marked with INSERTED)
+
+<details>
+<summary>✅ v1.0 Multi-Provider Support (Phases 1-6) - SHIPPED 2026-01-11</summary>
+
+### Phase 1: Provider Infrastructure
+**Goal**: Users can configure Replicate and fal.ai API keys in settings, with keys securely stored
+**Depends on**: Nothing (first phase)
+**Research**: Unlikely (internal UI patterns, Zustand state management)
+**Plans**: 2 plans
+
+Plans:
+- [x] 01-01: Provider settings UI in ProjectSetupModal
+- [x] 01-02: Provider abstraction layer and types
+
+### Phase 2: Model Discovery
+**Goal**: App can fetch and cache available models from enabled providers at runtime
+**Depends on**: Phase 1
+**Research**: Likely (external APIs)
+**Research topics**: Replicate model listing API endpoints, fal.ai model discovery endpoints, response schemas and pagination
+**Plans**: 3 plans
+
+Plans:
+- [x] 02-01: Replicate model fetching API route
+- [x] 02-02: fal.ai model fetching API route
+- [x] 02-03: Model caching and unified model interface
+
+### Phase 3: Generate Node Refactor
+**Goal**: NanoBanana node becomes GenerateImage node supporting any provider's image models
+**Depends on**: Phase 2
+**Research**: Unlikely (internal refactoring using existing patterns)
+**Design decision**: Separate nodes for image vs video generation (GenerateVideo added in Phase 6)
+**Plans**: 3 plans
+
+Plans:
+- [x] 03-01: Rename NanoBanana to GenerateImage, add model selector (image models only)
+- [x] 03-02: Provider-specific execution in generate API route
+- [x] 03-03: Backward compatibility for existing workflows
+
+### Phase 4: Model Search Dialog
+**Goal**: Users can browse models via floating action bar icons and searchable dialog
+**Depends on**: Phase 3
+**Research**: Unlikely (internal UI using React patterns)
+**Plans**: 2 plans
+
+Plans:
+- [x] 04-01: Floating action bar with provider icons
+- [x] 04-02: Model search dialog with filtering and selection
+
+### Phase 5: Image URL Server
+**Goal**: Local API endpoint serves workflow images as URLs for providers requiring URL inputs
+**Depends on**: Phase 3
+**Research**: Unlikely (Next.js API routes, existing patterns)
+**Plans**: 2 plans
+
+Plans:
+- [x] 05-01: Image serving endpoint and URL generation
+- [x] 05-02: Integration with generate node for URL-based providers
+
+### Phase 6: Video & Polish
+**Goal**: GenerateVideo node for video generation, video playback, custom parameters, edge cases
+**Depends on**: Phase 5
+**Research**: Likely (video handling)
+**Research topics**: HTML5 video element for base64/blob URLs, provider response formats for video content
+**Design decision**: GenerateVideo as separate node type (not combined with GenerateImage)
+**Plans**: 4 plans
+
+Plans:
+- [x] 06-01: GenerateVideo node with video-capable model selector
+- [x] 06-02: Video playback in output node
+- [x] 06-03: Custom model parameters from provider schemas
+- [x] 06-04: Edge case handling and final polish
+
+</details>
+
+<details>
+<summary>✅ v1.1 Improvements (Phases 7-14) - SHIPPED 2026-01-12</summary>
+
+**Milestone Goal:** Fix connection issues, improve error visibility, add video history, auto-size nodes, and polish UI
+
+#### Phase 7: Video Connections ✅
+
+**Goal**: Fix video handle connections to only allow valid targets (generateVideo, output)
+**Depends on**: Phase 6
+**Research**: Unlikely (internal connection validation patterns)
+**Plans**: 1 plan
+
+Plans:
+- [x] 07-01: Add video handle type and connection validation
+
+#### Phase 8: Error Display ✅
+
+**Goal**: Better error visibility with overlay display, not hidden by previous output
+**Depends on**: Phase 7
+**Research**: Unlikely (internal UI patterns)
+**Plans**: 1 plan
+
+Plans:
+- [x] 08-01: Error notifications with persistent toast and node overlays
+
+#### Phase 9: Video History ✅
+
+**Goal**: Add history carousel for generated videos matching image history pattern
+**Depends on**: Phase 8
+**Research**: Unlikely (existing image history pattern)
+**Plans**: 1 plan
+
+Plans:
+- [x] 09-01: Video history types, store support, load API, and carousel UI
+
+#### Phase 10: Node Autosizing ✅
+
+**Goal**: Auto-size nodes to output dimensions and aspect ratio
+**Depends on**: Phase 9
+**Research**: Unlikely (React Flow node sizing)
+**Plans**: 1 plan
+
+Plans:
+- [x] 10-01: Node dimension utility and auto-resize on output
+
+#### Phase 11: UI Polish ✅
+
+**Goal**: Flora UI alignment, header UI improvements, project settings, provider logos on nodes
+**Depends on**: Phase 10
+**Research**: Unlikely (internal UI work)
+**Plans**: 1 plan
+
+Plans:
+- [x] 11-01: Provider badges on nodes and header UI streamlining
+
+#### Phase 12: Model Improvements ✅
+
+**Goal**: Verify Replicate image models work, extend model cache TTL
+**Depends on**: Phase 11
+**Research**: Likely (Replicate API behavior verification)
+**Research topics**: Replicate image model endpoints, cache invalidation strategies
+**Plans**: 1 plan
+
+Plans:
+- [x] 12-01: Extended cache TTL, fixed isImageInput, fixed stale node data in execution
+
+#### Phase 13: Fix Duplicate Generations ✅
+
+**Goal**: Fix image deduplication - generations folder has duplicate images due to hashing failure
+**Depends on**: Phase 12
+**Research**: Likely (investigate current hashing implementation)
+**Research topics**: Current save-generation hashing logic, why duplicates are being created
+**Plans**: 1 plan
+
+Plans:
+- [x] 13-01: Add MD5 content hashing and deduplication to save-generation API
+
+#### Phase 14: Fix Drag-Connect Node Creation Bugs ✅
+
+**Goal**: Fix bugs with nodes created via drag-connect: (1) connection vanishes after selecting model from browser, (2) defaults to Gemini with missing model selector in header
+**Depends on**: Phase 13
+**Research**: Unlikely (React Flow connection state, node creation flow)
+**Research topics**: Connection state during node creation, model selection callbacks, createDefaultNodeData initialization
+**Plans**: 1 plan
+
+Plans:
+- [x] 14-01: Normalize dynamic handle IDs and fix connection persistence
+
+</details>
+
+### 🚧 v1.2 Improvements (In Progress)
+
+**Milestone Goal:** Add automated testing across the application, modularize large monolithic files for better maintainability, and improve cost tracking for multi-provider support
+
+#### Phase 15: Test Infrastructure
+
+**Goal**: Set up testing framework with Vitest and React Testing Library for Next.js 16
+**Depends on**: Phase 14
+**Research**: Likely (Vitest + Next.js 16 App Router setup)
+**Research topics**: Vitest configuration for Next.js 16, React Testing Library setup, test file organization
+**Plans**: TBD
+
+Plans:
+- [x] 15-01: React Testing Library setup and configuration
+
+#### Phase 16: Store Modularization ✅
+
+**Goal**: Break up workflowStore.ts into focused modules (execution, nodes, edges, persistence)
+**Depends on**: Phase 15
+**Research**: Unlikely (internal Zustand patterns)
+**Plans**: 1 plan
+
+Plans:
+- [x] 16-01: Extract localStorage helpers and node defaults to utility modules
+
+#### Phase 17: Component Tests
+
+**Goal**: Add tests for all 34 React components covering nodes, toolbars, modals, and edges
+**Depends on**: Phase 16
+**Research**: Unlikely (established React Testing Library patterns)
+**Plans**: 11 plans
+
+Plans:
+- [x] 17-01: Core Nodes (BaseNode, PromptNode, ImageInputNode)
+- [x] 17-02: Display Nodes (OutputNode, SplitGridNode, GroupNode)
+- [x] 17-03: Generate Nodes (GenerateImageNode, GenerateVideoNode)
+- [x] 17-04: Processing Nodes (LLMGenerateNode, AnnotationNode)
+- [x] 17-05: Toolbars (Header, FloatingActionBar, MultiSelectToolbar)
+- [x] 17-06: Canvas & Edges (WorkflowCanvas, EditableEdge, ReferenceEdge, EdgeToolbar)
+- [x] 17-07: Menus & Notifications (ConnectionDropMenu, Toast, CostIndicator)
+- [x] 17-08: Core Modals (ModelSearchDialog, ProjectSetupModal, CostDialog)
+- [x] 17-09: Editor Modals (PromptEditorModal, SplitGridSettingsModal, AnnotationModal)
+- [x] 17-10: Quickstart (WelcomeModal, QuickstartInitialView, QuickstartTemplatesView, PromptWorkflowView, QuickstartBackButton)
+- [x] 17-11: Utilities (GlobalImageHistory, GroupsOverlay, ModelParameters)
+
+#### Phase 18: API Route Tests
+
+**Goal**: Add tests for generate, llm, models, and workflow API routes
+**Depends on**: Phase 17
+**Research**: Unlikely (Next.js API route testing patterns)
+**Plans**: 5 plans
+
+Plans:
+- [x] 18-01: File I/O routes (workflow, save-generation)
+- [x] 18-02: LLM route (Google, OpenAI providers)
+- [x] 18-03: Generate route (Gemini provider)
+- [x] 18-04: Generate route (Replicate, fal.ai providers)
+- [x] 18-05: Models route (caching, aggregation)
+
+#### Phase 19: Type Refactoring
+
+**Goal**: Split types/index.ts into domain-specific type files (nodes, providers, workflow)
+**Depends on**: Phase 18
+**Research**: Unlikely (internal refactoring)
+**Plans**: 2 plans
+
+Plans:
+- [x] 19-01: Extract node and annotation types
+- [x] 19-02: Extract provider, workflow, API, and model types
+
+#### Phase 20: Integration Tests
+
+**Goal**: End-to-end workflow execution tests covering node connections and data flow
+**Depends on**: Phase 19
+**Research**: Unlikely (internal testing patterns)
+**Plans**: 2 plans
+
+Plans:
+- [x] 20-01: Store integration tests (getConnectedInputs, validateWorkflow, topological sort)
+- [x] 20-02: Workflow execution tests (data flow, error handling, connection validation)
+
+#### Phase 21: Fix Image Input & Deduplication Issues
+
+**Goal**: Fix Gemini nano-banana-pro model ignoring image inputs and resolve duplicate image saving across input/generated images
+**Depends on**: Phase 20
+**Research**: Likely (Gemini API image input handling, current hashing implementation)
+**Research topics**: Gemini 3 Pro image generation API requirements, why image inputs are ignored, current save logic for inputs vs generations
+**Plans**: 1 plan
+
+**Issues:**
+1. ~~nano-banana-pro model generates without considering image inputs~~ - RESOLVED (no longer an issue)
+2. Input and generated images have duplicate files despite different hashes - need consistent hashing approach matching video saving
+3. Generated images should be prepended with prompt details like generated videos
+
+Plans:
+- [x] 21-01: Unify MD5 hashing for image deduplication
+
+#### Phase 22: Generate Node Dynamic Input Tests
+
+**Goal**: Test that generate nodes properly validate and render dynamic inputs from provider schemas, and that all inputs/parameters are correctly included in API calls
+**Depends on**: Phase 21
+**Research**: Unlikely (existing test patterns from Phase 17)
+**Plans**: 1 plan
+
+**Test coverage:**
+1. Dynamic inputs from provider schemas render correctly as parameters and input handles on node creation
+2. Validation of dynamic inputs (required fields, type checking, constraints)
+3. Standard inputs (image, text) validate properly
+4. On submission, all parameters and inputs are included in API call payload correctly (covered by Phase 18)
+5. Coverage across all providers (Gemini, Replicate, fal.ai)
+
+Plans:
+- [x] 22-01: ModelParameters tests, GenerateImageNode/GenerateVideoNode dynamic handle tests
+
+#### Phase 23: Model Browser Improvements
+
+**Goal**: Improve model browser UX with recently used models section, icon-based provider dropdown with Gemini, and include Gemini models in browse list
+**Depends on**: Phase 22
+**Research**: Unlikely (existing UI patterns)
+**Plans**: TBD
+
+**Features:**
+1. Recently used models section at top of browse dialog showing last 4 models used
+2. Provider dropdown uses icons instead of text, add Gemini to the provider list
+3. Include Gemini models (nano-banana, nano-banana-pro) in the browsable model list alongside Replicate/fal.ai models
+
+Plans:
+- [x] 23-01: Recently used models, icon-based provider filter, Gemini models in browse
+
+#### Phase 24: Improved Cost Summary
+
+**Goal**: Expand cost tracking to include fal.ai models (via their pricing API), video generation nodes, and graceful handling for Replicate (no pricing API available)
+**Depends on**: Phase 23
+**Research**: Complete (see research notes below)
+**Plans**: 3 plans
+
+**Research Notes:**
+- fal.ai has a pricing API: `GET /v1/models/pricing?endpoint_id=model1,model2` returns `{ prices: [{ endpoint_id, unit_price, unit, currency }] }`
+- Replicate does NOT expose pricing via API (open GitHub issue, unresolved). Prediction response has `metrics.predict_time` but no hardware/cost info.
+- `ProviderModel` type already has `pricing?: { type, amount, currency }` field at `src/lib/providers/types.ts:69-74`
+
+**UX Decision: Provider-Grouped with Uncertainty Section**
+- Two sections: "Known Costs" (Gemini + fal.ai) and "Pricing Unavailable" (Replicate)
+- Known costs show total at section header, breakdown by provider with icons
+- fal.ai items show billing unit from API (e.g., "per image", "per 5s video")
+- Replicate section includes help text: "Pricing varies by hardware and runtime. Check replicate.com"
+- Incurred cost only tracks Gemini & fal.ai (Replicate excluded with note)
+- Empty provider sections hidden
+
+**Features:**
+1. Fetch fal.ai model pricing via their pricing API and populate `ProviderModel.pricing`
+2. Track generateVideo nodes in cost predictions (currently ignored)
+3. For Replicate models: display "pricing unavailable" gracefully in dedicated section
+4. Update CostDialog with two-section layout: Known Costs (Gemini, fal.ai) and Pricing Unavailable (Replicate)
+5. Show billing units for fal.ai models (per image, per second of video, etc.)
+6. Incurred cost excludes Replicate with explanatory note
+
+Plans:
+- [x] 24-01: fal.ai pricing API integration and ProviderModel.pricing population
+- [x] 24-02: Expand costCalculator to handle video nodes and external providers
+- [x] 24-03: Update CostDialog UI for multi-provider breakdown
+
+<details>
+<summary>✅ v1.3 Improvements (Phases 25-30) - SHIPPED 2026-01-24</summary>
+
+**Milestone Goal:** Add rich template exploration with search/filters, node default preferences in settings, and canvas performance optimizations
+
+#### Phase 25: Template Explorer UI
+
+**Goal**: Full template exploration interface with cards layout, left-hand filter/search panel, supporting many templates
+**Depends on**: Phase 24
+**Research**: Unlikely (internal UI patterns)
+**Plans**: 2 plans
+
+**Features:**
+- Cards layout for template browsing (scalable for many templates)
+- Left-hand panel with search and category filters
+- Template metadata display (name, description, node count, etc.)
+- Replace current quickstart template selection
+
+Plans:
+- [x] 25-01: Template types, TemplateCard component, TemplateExplorerView grid layout
+- [x] 25-02: Sidebar filters (search, category, tags), WelcomeModal integration
+
+#### Phase 26: Template Preview Rendering ✅
+
+**Goal**: Visual preview of workflow templates showing node layout and connections before loading
+**Depends on**: Phase 25
+**Research**: Unlikely (React Flow rendering, existing patterns)
+**Plans**: 1 plan
+
+**Final Implementation:**
+- Horizontal card layout with thumbnail image, details, and "Use workflow" button
+- Two-column grid layout for better scanning
+- Conditional dialog width (6xl for explorer, 2xl for other views)
+- Direct workflow loading without intermediate modal
+
+Plans:
+- [x] 26-01: Horizontal cards with direct workflow loading, conditional dialog sizing
+
+#### Phase 27: Node Defaults Infrastructure ✅
+
+**Goal**: Store default model and settings preferences per node type in localStorage
+**Depends on**: Phase 26
+**Research**: Unlikely (localStorage, existing patterns)
+**Plans**: 1 plan
+
+**Features:**
+- Schema for node type defaults (model, parameters, settings)
+- Apply defaults when creating nodes via keyboard shortcuts (Shift+G, etc.)
+- Per-provider model defaults (e.g., default fal.ai model for GenerateImage)
+
+Plans:
+- [x] 27-01: NodeDefaultsConfig types, localStorage helpers, createDefaultNodeData integration
+
+#### Phase 28: Node Defaults UI ✅
+
+**Goal**: Settings panel for configuring default node preferences per node type
+**Depends on**: Phase 27
+**Research**: Unlikely (internal UI patterns)
+**Plans**: 1 plan
+
+**Features:**
+- Section in settings for node defaults
+- Select default model per node type (GenerateImage, GenerateVideo, LLM)
+- Configure default parameters (e.g., seedream 4.5 with specific settings)
+- Clear/reset to system defaults
+- Shift+V keyboard shortcut for video nodes
+
+Plans:
+- [x] 28-01: Node Defaults tab in ProjectSetupModal with model selection and LLM controls
+
+#### Phase 29: Canvas Performance
+
+**Goal**: Optimize canvas rendering for large workflows using virtualization and memoization
+**Depends on**: Phase 28
+**Research**: Likely (React Flow virtualization, performance optimization)
+**Research topics**: React Flow performance best practices, node virtualization, selective rendering
+**Plans**: TBD
+
+Plans:
+- [ ] 29-01: TBD (run /gsd:plan-phase 29 to break down)
+
+#### Phase 30: Small Fixes
+
+**Goal**: [To be planned]
+**Depends on**: Phase 29
+**Research**: Unlikely
+**Plans**: TBD
+
+Plans:
+- [ ] 30-01: TBD (run /gsd:plan-phase 30 to break down)
+
+</details>
+
+### 🚧 v1.4 Features (In Progress)
+
+**Milestone Goal:** Transform the Prompt-to-Workflow feature into a full agentic workflow builder with proposal dialogs, chat-based editing, and safe file handling for large workflows
+
+#### Phase 31: Workflow Proposal System
+
+**Goal**: Agent proposes workflow details before building with user feedback/approve flow
+**Depends on**: Phase 30
+**Research**: Likely (LLM prompting for structured proposals)
+**Research topics**: Structured output formats for workflow proposals, dialog UX patterns for agent communication
+**Plans**: TBD
+
+Plans:
+- [x] 31-01: Workflow proposal types, prompt, and API endpoint
+- [x] 31-02: Chat infrastructure (Vercel AI SDK, streaming endpoint, types)
+
+#### Phase 32: Chat UI Foundation
+
+**Goal**: Floating chat window above minimap using Vercel AI SDK patterns
+**Depends on**: Phase 31
+**Research**: Likely (Vercel AI SDK, chat UI components)
+**Research topics**: Vercel AI SDK (ai package) integration, useChat hook, streaming responses, chat UI component patterns
+**Plans**: TBD
+
+Plans:
+- [ ] 32-01: TBD (run /gsd:plan-phase 32 to break down)
+
+#### Phase 33: Workflow Edit Safety
+
+**Goal**: Original file preservation before edits with accept/reject change flow
+**Depends on**: Phase 32
+**Research**: Likely (versioning strategies, JSON diffing)
+**Research topics**: Shadow copy vs diff-based vs undo stack approaches, JSON diff visualization
+**Plans**: TBD
+
+Plans:
+- [ ] 33-01: TBD (run /gsd:plan-phase 33 to break down)
+
+#### Phase 34: Agentic Workflow Editing
+
+**Goal**: Agent interprets edit requests and modifies workflow JSON with change narration
+**Depends on**: Phase 33
+**Research**: Likely (system prompts for structured edits)
+**Research topics**: System prompts for JSON file updates, structured output for workflow modifications, change explanation patterns
+**Plans**: TBD
+
+Plans:
+- [ ] 34-01: TBD (run /gsd:plan-phase 34 to break down)
+
+#### Phase 35: Large Workflow Handling
+
+**Goal**: Handle workflows with base64 images/videos efficiently, token management
+**Depends on**: Phase 34
+**Research**: Likely (chunking, context window strategies)
+**Research topics**: Token optimization for large payloads, base64 extraction/reinsertion, workflow summarization techniques
+**Plans**: TBD
+
+Plans:
+- [ ] 35-01: TBD (run /gsd:plan-phase 35 to break down)
+
+### 📋 v1.5 Store Refactoring (Planned)
+
+**Milestone Goal:** Major refactoring of workflowStore.ts (2,900+ lines) into modular, testable components. Extract execution engine, create Zustand slices, and improve code maintainability while maintaining full backward compatibility.
+
+**Problem Statement:**
+- `workflowStore.ts` is 2,907 lines with 15+ mixed concerns
+- `executeWorkflow` (~800 lines) and `regenerateNode` (~600 lines) contain node-specific logic for 8 node types inline
+- Duplicated patterns (provider header building repeated 6+ times)
+- Difficult to test individual concerns
+- High cognitive load for any modifications
+
+**Target Architecture:**
+```
+src/store/
+├── workflowStore.ts          # ~100 lines - combines slices
+├── slices/                   # Zustand slice pattern
+│   ├── coreSlice.ts          # nodes, edges, clipboard
+│   ├── groupsSlice.ts        # group operations
+│   ├── executionSlice.ts     # execution state & actions
+│   ├── persistenceSlice.ts   # save/load, auto-save
+│   ├── uiSlice.ts            # modal state, quickstart
+│   ├── costSlice.ts          # cost tracking
+│   ├── providersSlice.ts     # provider settings
+│   ├── historySlice.ts       # global history, recent models
+│   └── commentsSlice.ts      # comment navigation
+├── execution/                # Modular execution engine
+│   ├── engine.ts             # Core orchestration
+│   ├── helpers.ts            # Shared utilities
+│   └── executors/            # Per-node-type executors
+└── utils/                    # Pure helper functions
+```
+
+#### Phase 36: Execution Engine Extraction
+
+**Goal**: Extract the massive executeWorkflow and regenerateNode functions into a modular execution engine with per-node-type executors
+**Depends on**: Phase 35
+**Research**: Unlikely (internal Zustand patterns, existing codebase)
+**Plans**: 3 plans
+
+**Scope:**
+- Create `src/store/execution/` directory structure
+- Extract execution types and interfaces
+- Create node executor interface and registry
+- Extract all 8 node-type executors (imageInput, annotation, prompt, nanoBanana, generateVideo, llmGenerate, splitGrid, output)
+- Extract shared helpers (buildProviderHeaders, trackSaveGeneration, waitForPendingImageSyncs)
+- Integrate engine back into workflowStore with same public API
+
+Plans:
+- [ ] 36-01: Execution types, helpers, and engine orchestration
+- [ ] 36-02: Node executors (all 8 types) with tests
+- [ ] 36-03: Integrate engine with store, backward compatibility verification
+
+#### Phase 37: Pure Helpers Extraction
+
+**Goal**: Extract pure functions from the store into testable utility modules
+**Depends on**: Phase 36
+**Research**: Unlikely (internal refactoring)
+**Plans**: 2 plans
+
+**Scope:**
+- Extract `getConnectedInputs` as pure function
+- Extract `validateWorkflow` as pure function
+- Extract `topologicalSort` logic
+- Extract workflow migration logic (legacy nanoBanana nodes)
+- Extract `clearNodeImageRefs` helper
+
+Plans:
+- [ ] 37-01: getConnectedInputs, validateWorkflow, topologicalSort with tests
+- [ ] 37-02: workflowMigration, clearNodeImageRefs with tests
+
+#### Phase 38: Zustand Slice Pattern
+
+**Goal**: Split monolithic store into composable Zustand slices for better separation of concerns
+**Depends on**: Phase 37
+**Research**: Unlikely (Zustand slice patterns)
+**Plans**: 3 plans
+
+**Scope:**
+- Create slice pattern infrastructure
+- Extract core slice (nodes, edges, edgeStyle, clipboard operations)
+- Extract groups slice (all group operations)
+- Extract execution slice (isRunning, currentNodeId, execute/regenerate actions)
+- Extract persistence slice (save/load, auto-save, workflow metadata)
+- Extract UI slice (modal count, quickstart, model search)
+- Extract cost slice (incurredCost, cost tracking actions)
+- Extract providers slice (providerSettings, API key management)
+- Extract history slice (globalImageHistory, recentModels)
+- Extract comments slice (comment navigation state)
+
+Plans:
+- [ ] 38-01: Core slices (core, groups, execution) with tests
+- [ ] 38-02: Feature slices (persistence, UI, cost, providers) with tests
+- [ ] 38-03: Remaining slices (history, comments), final store composition
+
+#### Phase 39: Type Extraction & Final Integration
+
+**Goal**: Move store types to proper locations and verify full backward compatibility
+**Depends on**: Phase 38
+**Research**: Unlikely (internal refactoring)
+**Plans**: 1 plan
+
+**Scope:**
+- Extract `WorkflowStore`, `WorkflowFile`, `ClipboardData`, `EdgeStyle` to `src/types/store.ts`
+- Update all imports across codebase
+- Verify all existing tests pass
+- Verify all re-exports maintain backward compatibility
+- Final cleanup and documentation
+
+Plans:
+- [ ] 39-01: Extract store types, verify backward compatibility, final cleanup
+
+## Progress
+
+**Execution Order:**
+Phases execute in numeric order: 1 → 2 → ... → 35 → 36 → 37 → 38 → 39
+
+| Phase | Milestone | Plans Complete | Status | Completed |
+|-------|-----------|----------------|--------|-----------|
+| 1. Provider Infrastructure | v1.0 | 2/2 | Complete | 2026-01-09 |
+| 2. Model Discovery | v1.0 | 3/3 | Complete | 2026-01-09 |
+| 3. Generate Node Refactor | v1.0 | 3/3 | Complete | 2026-01-09 |
+| 4. Model Search Dialog | v1.0 | 2/2 | Complete | 2026-01-09 |
+| 5. Image URL Server | v1.0 | 2/2 | Complete | 2026-01-09 |
+| 6. Video & Polish | v1.0 | 4/4 | Complete | 2026-01-11 |
+| 7. Video Connections | v1.1 | 1/1 | Complete | 2026-01-12 |
+| 8. Error Display | v1.1 | 1/1 | Complete | 2026-01-12 |
+| 9. Video History | v1.1 | 1/1 | Complete | 2026-01-12 |
+| 10. Node Autosizing | v1.1 | 1/1 | Complete | 2026-01-12 |
+| 11. UI Polish | v1.1 | 1/1 | Complete | 2026-01-12 |
+| 12. Model Improvements | v1.1 | 1/1 | Complete | 2026-01-12 |
+| 13. Fix Duplicate Generations | v1.1 | 1/1 | Complete | 2026-01-12 |
+| 14. Fix Drag-Connect Node Creation Bugs | v1.1 | 1/1 | Complete | 2026-01-12 |
+| 15. Test Infrastructure | v1.2 | 1/1 | Complete | 2026-01-12 |
+| 16. Store Modularization | v1.2 | 1/1 | Complete | 2026-01-12 |
+| 17. Component Tests | v1.2 | 11/11 | Complete | 2026-01-13 |
+| 18. API Route Tests | v1.2 | 5/5 | Complete | 2026-01-13 |
+| 19. Type Refactoring | v1.2 | 2/2 | Complete | 2026-01-13 |
+| 20. Integration Tests | v1.2 | 2/2 | Complete | 2026-01-13 |
+| 21. Fix Image Input & Deduplication | v1.2 | 1/1 | Complete | 2026-01-13 |
+| 22. Generate Node Dynamic Input Tests | v1.2 | 1/1 | Complete | 2026-01-13 |
+| 23. Model Browser Improvements | v1.2 | 1/1 | Complete | 2026-01-13 |
+| 24. Improved Cost Summary | v1.2 | 3/3 | Complete | 2026-01-17 |
+| 25. Template Explorer UI | v1.3 | 2/2 | Complete | 2026-01-16 |
+| 26. Template Preview Rendering | v1.3 | 1/1 | Complete | 2026-01-17 |
+| 27. Node Defaults Infrastructure | v1.3 | 1/1 | Complete | 2026-01-17 |
+| 28. Node Defaults UI | v1.3 | 1/1 | Complete | 2026-01-17 |
+| 29. Canvas Performance | v1.3 | 0/0 | Deferred | - |
+| 30. Small Fixes | v1.3 | 0/0 | Deferred | - |
+| 31. Workflow Proposal System | v1.4 | 2/2 | Complete | 2026-01-26 |
+| 32. Chat UI Foundation | v1.4 | 0/? | Not started | - |
+| 33. Workflow Edit Safety | v1.4 | 0/? | Not started | - |
+| 34. Agentic Workflow Editing | v1.4 | 0/? | Not started | - |
+| 35. Large Workflow Handling | v1.4 | 0/? | Not started | - |
+| 36. Execution Engine Extraction | v1.5 | 0/3 | Not started | - |
+| 37. Pure Helpers Extraction | v1.5 | 0/2 | Not started | - |
+| 38. Zustand Slice Pattern | v1.5 | 0/3 | Not started | - |
+| 39. Type Extraction & Final Integration | v1.5 | 0/1 | Not started | - |
diff --git a/.planning/STATE.md b/.planning/STATE.md
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+++ b/.planning/STATE.md
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+# Project State
+
+## Project Reference
+
+See: .planning/PROJECT.md (updated 2026-01-09)
+
+**Core value:** Provider infrastructure that dynamically discovers models from external APIs, enabling users to access hundreds of image/video generation models without hardcoding schemas.
+**Current focus:** Agentic workflow builder (v1.4), then Store Refactoring (v1.5)
+
+## Current Position
+
+Phase: 31 of 35 (Workflow Proposal System)
+Plan: 2 of 2 in current phase
+Status: Phase complete
+Last activity: 2026-01-26 - Completed 31-02-PLAN.md
+
+Progress: ░░░░░░░░░░ 6%
+
+## Performance Metrics
+
+**Velocity:**
+- Total plans completed: 28
+- Average duration: 7 min
+- Total execution time: 3.4 hours
+
+**By Phase:**
+
+| Phase | Plans | Total | Avg/Plan |
+|-------|-------|-------|----------|
+| 1. Provider Infrastructure | 2/2 | 14 min | 7 min |
+| 2. Model Discovery | 3/3 | 14 min | 4.7 min |
+| 3. Generate Node Refactor | 3/3 | 13 min | 4.3 min |
+| 4. Model Search Dialog | 2/2 | 17 min | 8.5 min |
+| 5. Image URL Server | 2/2 | 5 min | 2.5 min |
+| 6. Video & Polish | 4/4 | 43 min | 14.3 min |
+| 7. Video Connections | 1/1 | 4 min | 4 min |
+| 8. Error Display | 1/1 | 14 min | 14 min |
+| 9. Video History | 1/1 | 12 min | 12 min |
+| 10. Node Autosizing | 1/1 | 2 min | 2 min |
+| 11. UI Polish | 1/1 | 8 min | 8 min |
+| 12. Model Improvements | 1/1 | - | - |
+| 13. Fix Duplicate Generations | 1/1 | 1 min | 1 min |
+| 14. Fix Drag-Connect Bugs | 1/1 | 7 min | 7 min |
+| 15. Test Infrastructure | 1/1 | 3 min | 3 min |
+| 16. Store Modularization | 1/1 | 22 min | 22 min |
+| 19. Type Refactoring | 2/2 | 16 min | 8 min |
+| 22. Generate Node Dynamic Input Tests | 1/1 | 20 min | 20 min |
+| 23. Model Browser Improvements | 1/1 | 5 min | 5 min |
+| 20. Integration Tests | 2/2 | 11 min | 5.5 min |
+| 24. Improved Cost Summary | 3/3 | 25 min | 8 min |
+| 25. Template Explorer UI | 2/2 | 23 min | 11.5 min |
+| 26. Template Preview Rendering | 1/1 | 25 min | 25 min |
+| 27. Node Defaults Infrastructure | 1/1 | 15 min | 15 min |
+| 28. Node Defaults UI | 1/1 | 32 min | 32 min |
+| 31. Workflow Proposal System | 2/2 | 6 min | 3 min |
+
+**Recent Trend:**
+- Last 5 plans: 25 min, 15 min, 32 min, 4 min, 2 min
+- Trend: Infrastructure plans (types, API) completing quickly
+
+## Accumulated Context
+
+### Decisions
+
+Decisions are logged in PROJECT.md Key Decisions table.
+Recent decisions affecting current work:
+
+- Gemini always enabled via env var (GEMINI_API_KEY), Replicate/fal.ai optional
+- API keys stored in localStorage under node-banana-provider-settings key
+- Local state in modal to avoid saving on every keystroke
+- Provider config pattern: {id, name, enabled, apiKey, apiKeyEnvVar?}
+- Provider registry uses self-registration pattern via registerProvider()
+- Gemini remains special-cased in /api/generate for now, not yet migrated
+- Capability inference from model name/description keywords
+- fal.ai API key optional (works without but rate limited)
+- fal.ai auth header: "Key {apiKey}" format (not Bearer)
+- fal.ai category maps directly to ModelCapability (no inference)
+- 1-hour cache TTL for model lists (extended from 10 min)
+- Unified API at /api/models with header-based auth
+- Provider dropdown shows Gemini always, others only if API key configured
+- Aspect ratio/resolution controls shown only for Gemini provider
+- Backward compatibility via aliases: NanoBananaNode, saveNanoBananaDefaults
+- Server-side provider execution in API route (not client-side)
+- Header-based API key passing: X-Replicate-API-Key, X-Fal-API-Key
+- fal.ai sync API (fal.run) instead of queue-based async
+- Dual migration approach: loadWorkflow migrates + UI effect for runtime
+- fal.ai icon always visible in action bar (works without key but rate limited)
+- Replicate icon only visible when API key is configured
+- Client-side search filtering for Replicate (their search API unreliable)
+- Show all capability badges to differentiate similar models
+- Extract variant suffix from fal.ai model IDs for display name
+- No TTL for image store - explicit cleanup pattern (callers delete after use)
+- 256KB threshold for shouldUseImageUrl (Replicate recommendation)
+- Gemini excluded from video node (doesn't support video generation)
+- Large videos (>20MB) return URL instead of base64 to avoid memory issues
+- Fetch schema from provider API at model selection time with 10-min cache
+- Filter internal params, prioritize user-relevant ones (seed, steps, guidance)
+- Collapsible parameters section to keep node UI compact
+- Node autosizing constraints: 200-500px width, 200-600px height, ~100px chrome
+- Provider badges prepend node title (left side) with w-4 h-4 icons
+- Node titles show only model name (no "Generate Image/Video" prefix)
+- BaseNode supports titlePrefix prop for icon prepending
+- Header aligned for saved/unsaved states with same icon layout
+- isImageInput() uses word-boundary checks (not substring) to avoid matching num_images
+- Workflow execution gets fresh node data from store (not stale captured array)
+- regenerateNode includes parameters in request body
+- MD5 content hashing for generation deduplication (fast, collision resistance not critical)
+- Hash prefix in filename for O(1) duplicate lookup
+- Normalized handle IDs (image, text, image-0) for connection stability across model changes
+- Handle-to-schema mapping built at execution time from inputSchema
+- Placeholder handles (dimmed 30%) for input types not used by model, preserving connections
+- ReactFlowProvider wrapper for component tests using @xyflow/react hooks
+- Zustand store mocking with vi.mock pattern returning mocked functions
+- Vitest jsdom environment for React component tests
+- Store utilities extracted to src/store/utils/ with re-exports for backward compatibility
+- Consolidated defaultNodeDimensions (was duplicated in addNode and createGroup)
+- localStorage mocking pattern for testing utility modules
+- Type domain files live in src/types/*.ts with re-exports from index.ts
+- BaseNodeData in annotation.ts to avoid circular imports (nodes.ts imports annotation.ts)
+- 7 type domain files: annotation, nodes, providers, models, workflow, api, quickstart
+- index.ts is pure re-export hub with no type definitions
+- Max 8 recent models stored in localStorage, 4 displayed in UI
+- Gemini models hardcoded in /api/models (not fetched from external API)
+- Green color theme for Gemini provider (bg-green-500/20 text-green-300)
+- Cost dialog: Gemini Cost section (with prices) + External Providers section (with model links)
+- External provider pricing removed (fal.ai 429 errors, Replicate no API) - show model links instead
+- Incurred cost only tracks Gemini generations
+- Template category colors: blue=product, purple=style, green=composition, amber=community
+- Template grid layout: 2 cols mobile, 3 cols lg+
+- Template node count calculated at runtime from workflow.nodes.length
+- onWheelCapture pattern for isolating modal scroll from React Flow canvas
+- min-h-0 on flexbox containers enables overflow scrolling
+- overflow-clip instead of overflow-hidden when child needs scroll
+- Node defaults UI uses local state pattern (load on open, save on button click)
+- ModelSearchDialog reused with onModelSelected callback for defaults UI
+- LLM_PROVIDERS/LLM_MODELS duplicated from LLMGenerateNode (not exported)
+- Shift+V keyboard shortcut for video node creation
+- Proposal types focus on purpose/description, not internal state or positions
+- Reuse parseJSONFromResponse from validation.ts for consistent JSON parsing
+- Validate proposal shape before returning to catch LLM errors early
+- Use createGoogleGenerativeAI factory for custom API key injection (AI SDK)
+- toTextStreamResponse for AI SDK v6 streaming (not toDataStreamResponse)
+
+### Deferred Issues
+
+- UAT-001: Resolved - Provider icons now use real Replicate/fal.ai logos
+- ISS-001: Resolved - Generate nodes now adapt to model requirements via dynamic parameters
+
+### Blockers/Concerns
+
+- Pre-existing lint configuration issue (ESLint not configured). Not blocking development.
+
+### Roadmap Evolution
+
+- v1.0 Multi-Provider Support shipped: 6 phases (Phase 1-6), 15 plans
+- Milestone v1.1 Improvements created: 6 phases (Phase 7-12), improvements and polish
+- Phase 13 added: Fix duplicate generations (hashing failure investigation)
+- Phase 14 added: Fix drag-connect node creation bugs (consolidated from two phases)
+- Milestone v1.2 Improvements created: 6 phases (Phase 15-20), testing and modularization
+- Phase 21 added: Fix Gemini Pro image input handling and image deduplication issues
+- Phase 22 added: Generate node dynamic input validation and API call tests
+- Phase 23 added: Model browser improvements (recently used, icon dropdown, Gemini models in list)
+- Phase 24 added: Improved cost summary (fal.ai pricing API, video node tracking, multi-provider support)
+- Milestone v1.3 Improvements created: 5 phases (Phase 25-29), template explorer, node defaults, canvas performance
+- Phase 30 added: Small fixes
+- Milestone v1.4 Features created: 5 phases (Phase 31-35), agentic workflow builder with proposal dialogs and chat-based editing
+- Milestone v1.5 Store Refactoring created: 4 phases (Phase 36-39), major refactor of workflowStore.ts into modular execution engine and Zustand slices
+
+## Session Continuity
+
+Last session: 2026-01-26
+Stopped at: Completed 31-02-PLAN.md
+Resume file: None
+Next action: Plan Phase 32 (Chat UI Integration)
diff --git a/.planning/phases/31-workflow-proposal-system/31-02-SUMMARY.md b/.planning/phases/31-workflow-proposal-system/31-02-SUMMARY.md
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+++ b/.planning/phases/31-workflow-proposal-system/31-02-SUMMARY.md
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+---
+phase: 31-workflow-proposal-system
+plan: 02
+subsystem: api
+tags: [vercel-ai-sdk, streaming, gemini, chat, ai-sdk-google]
+
+# Dependency graph
+requires:
+  - phase: 31-01
+    provides: WorkflowProposal types, domain prompts
+provides:
+  - Streaming /api/chat endpoint
+  - Chat types (ChatMessage, ChatRole, ConversationState)
+  - Vercel AI SDK integration with Gemini
+affects: [31-03-chat-ui, workflow-planning]
+
+# Tech tracking
+tech-stack:
+  added: [ai@6.0.49, @ai-sdk/google@3.0.13]
+  patterns: [createGoogleGenerativeAI, streamText, toTextStreamResponse]
+
+key-files:
+  created:
+    - src/types/chat.ts
+    - src/app/api/chat/route.ts
+  modified:
+    - src/types/index.ts
+    - package.json
+
+key-decisions:
+  - "Use createGoogleGenerativeAI factory for custom API key injection"
+  - "toTextStreamResponse for AI SDK v6 streaming (not toDataStreamResponse)"
+  - "System prompt contains full Node Banana domain expertise for conversational planning"
+
+patterns-established:
+  - "Vercel AI SDK streaming pattern: createGoogleGenerativeAI → streamText → toTextStreamResponse"
+
+issues-created: []
+
+# Metrics
+duration: 2min
+completed: 2026-01-26
+---
+
+# Phase 31 Plan 02: Chat Infrastructure Summary
+
+**Streaming chat endpoint with Vercel AI SDK, Gemini integration, and conversational workflow planning assistant**
+
+## Performance
+
+- **Duration:** 2 min
+- **Started:** 2026-01-26T09:37:57Z
+- **Completed:** 2026-01-26T09:40:07Z
+- **Tasks:** 4
+- **Files modified:** 4
+
+## Accomplishments
+- Installed Vercel AI SDK packages (ai, @ai-sdk/google)
+- Created chat types for conversation state management
+- Built streaming /api/chat endpoint with domain expertise
+- Exported chat types from central type index
+
+## Task Commits
+
+Each task was committed atomically:
+
+1. **Task 1: Install Vercel AI SDK packages** - `744e0a7` (chore)
+2. **Task 2: Create chat types** - `b263c03` (feat)
+3. **Task 3: Create streaming chat endpoint** - `727e54d` (feat)
+4. **Task 4: Update type exports** - `e558777` (feat)
+
+## Files Created/Modified
+- `src/types/chat.ts` - ChatMessage, ChatRole, ConversationState, ChatRequest types
+- `src/app/api/chat/route.ts` - Streaming POST endpoint with Node Banana system prompt
+- `src/types/index.ts` - Added chat types re-export
+- `package.json` - Added ai and @ai-sdk/google dependencies
+
+## Decisions Made
+- Used `createGoogleGenerativeAI` factory instead of default `google` export to inject API key from GEMINI_API_KEY env var
+- Used `toTextStreamResponse()` which is the correct method in AI SDK v6 (not toDataStreamResponse)
+- System prompt includes comprehensive Node Banana domain knowledge for conversational workflow planning
+
+## Deviations from Plan
+
+### Auto-fixed Issues
+
+**1. [Rule 3 - Blocking] Fixed google() API usage**
+- **Found during:** Task 3 (Create streaming chat endpoint)
+- **Issue:** Plan specified `google('gemini-2.5-flash', { apiKey })` but @ai-sdk/google doesn't accept second argument
+- **Fix:** Used `createGoogleGenerativeAI({ apiKey })` factory to create provider with custom API key
+- **Files modified:** src/app/api/chat/route.ts
+- **Verification:** Build succeeds
+- **Committed in:** 727e54d (Task 3 commit)
+
+**2. [Rule 3 - Blocking] Fixed streaming response method**
+- **Found during:** Task 3 (Create streaming chat endpoint)
+- **Issue:** `toDataStreamResponse()` doesn't exist in AI SDK v6
+- **Fix:** Changed to `toTextStreamResponse()` which is the correct method
+- **Files modified:** src/app/api/chat/route.ts
+- **Verification:** Build succeeds
+- **Committed in:** 727e54d (Task 3 commit)
+
+---
+
+**Total deviations:** 2 auto-fixed (2 blocking)
+**Impact on plan:** Both fixes required for build to succeed. API signature differences between plan and actual AI SDK v6.
+
+## Issues Encountered
+None beyond the API fixes above.
+
+## Next Phase Readiness
+- Chat streaming infrastructure complete
+- Ready for Chat UI integration in WelcomeModal (31-03)
+- Vercel AI SDK useChat hook can connect to /api/chat endpoint
+
+---
+*Phase: 31-workflow-proposal-system*
+*Completed: 2026-01-26*