fIx: smaller nits

frontend/src/components/nodes/render/useRenderingNodeState.ts

@@ -2,6 +2,57 @@
  * runs the resolve → render pipeline, manages streaming/cache,
  * and exposes derived state for the dumb UI. See lib/graph/rendering.ts for the
  * pipeline interface.
+ * 
+ * ## Auto vs Manual Mode Decision Tree
+ * 
+ * The hook supports two update modes: 'auto' and 'manual'. The mode is determined by:
+ * 
+ * 1. **Node data override**: Check `data?.updateMode` first
+ * 2. **Source logic default**: Fall back to `sourceLogic?.defaultUpdateMode`
+ * 3. **Hardcoded default**: Default to 'auto' if neither is set
+ * 
+ * ### Auto Mode Behavior
+ * - Runs automatically when upstream data changes (sourceSignature changes)
+ * - Debounces runs by 250ms to avoid excessive computation
+ * - Skips runs when node becomes visible with cache (visibility grace period: 400ms)
+ * - Updates path trigger on each run
+ * 
+ * ### Manual Mode Behavior
+ * - Only runs when `runTrigger` increments (user clicks "Run")
+ * - Requires explicit user action to update output
+ * - Caches last run signature to prevent re-runs on unrelated changes
+ * 
+ * ## Effect Dependencies
+ * 
+ * The main effect depends on:
+ * - `id`: Node ID (re-run when node changes)
+ * - `srcId`: Source node ID (re-run when connection changes)
+ * - `srcNode?.type`: Source node type (re-run when source type changes)
+ * - `effectiveUpdateMode`: Auto vs manual mode
+ * - `runTrigger`: Run trigger counter (for manual mode)
+ * - `sourceSignature`: Combined signature of all upstream nodes
+ * - `viewportWidth/Height`: Viewport dimensions (affects rendering)
+ * - `retryCount`: Retry counter (for error recovery)
+ * - `incomingIds.length`: Number of incoming connections
+ * 
+ * ## Rendering Pipeline
+ * 
+ * 1. **Resolve**: Source node (config/agent) produces resolved content
+ * 2. **Render**: Output type renderer (plantuml/markdown/wireframe) produces HTML/SVG
+ * 3. **Cache**: Results are cached in node data for persistence
+ * 4. **Display**: UI consumes the rendered content
+ * 
+ * ## Streaming Support
+ * 
+ * When the source node supports streaming (e.g., agent nodes):
+ * - `onStreamingStart`: Called when streaming begins
+ * - `onStreamingChunk`: Called for each chunk of markdown content
+ * - Streaming content is parsed with marked.js for preview
+ * 
+ * ## Error Handling
+ * 
+ * Errors during resolve or render are caught and stored in the `error` state.
+ * The error includes a `kind` (e.g., 'render', 'no-content') and `message`.
  */
 
 import { useCallback, useDeferredValue, useEffect, useMemo, useRef, useState } from 'react'