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+# callAiContent Process Flow
+
+## Function: `callAiContent(prompt, options, contentParts, outputFormat, title, parentOperationId)`
+
+### High-Level Flow
+
+```
+START callAiContent
+│
+├─> Initialize operation tracking (aiOperationId)
+├─> Determine operationType (if not set)
+│
+├─> [BRANCH 1] IMAGE_GENERATE → Handle image generation → RETURN
+│
+├─> [BRANCH 2] WEB_SEARCH/WEB_CRAWL → Handle web operations → RETURN
+│
+└─> [BRANCH 3] Unified Document Generation Path (outputFormat always set, defaults to "txt")
+    │
+    ├─> IF contentParts provided:
+    │   │
+    │   ├─> SEPARATE parts:
+    │   │   ├─> imageParts = [typeGroup=="image" OR mimeType starts "image/"]
+    │   │   ├─> textParts = [typeGroup in ["text","table","structure"] OR mimeType starts "text/"]
+    │   │   └─> otherParts = [rest] → SKIP
+    │   │
+    │   ├─> [PART 2.1] PROCESS IMAGES:
+    │   │   FOR each imagePart:
+    │   │   ├─> Create AiCallRequest with USER PROMPT + IMAGE_ANALYSE
+    │   │   ├─> Call aiObjects.call() → vision model extracts data
+    │   │   └─> Replace imagePart with text ContentPart (extracted data)
+    │   │
+    │   ├─> [PART 2.2] ADD TEXT PARTS as-is
+    │   │
+    │   └─> Convert processedParts to text string → content_for_generation
+    │
+    ├─> Build generation prompt (includes content_for_generation)
+    ├─> Call _callAiWithLooping for JSON generation
+    ├─> Parse JSON and render to outputFormat (txt, docx, xlsx, pdf, etc.)
+    └─> RETURN AiResponse with rendered document
+```
+
+### Detailed Flow: Unified Document Generation Path (lines 1055-1257)
+
+```
+IF outputFormat specified:
+│
+├─> IF contentParts provided:
+│   │
+│   ├─> SEPARATE parts (same logic as text path):
+│   │   ├─> imageParts, textParts, otherParts
+│   │
+│   ├─> [PART 2.1] PROCESS IMAGES:
+│   │   └─> Same as text path: vision models with USER PROMPT
+│   │
+│   ├─> [PART 2.2] ADD TEXT PARTS as-is
+│   │
+│   └─> Convert processedParts to text:
+│       └─> content_for_generation = "\n\n".join([...])
+│
+├─> Build generation prompt:
+│   └─> generation_prompt = buildGenerationPrompt(outputFormat, prompt, title, content_for_generation, None)
+│
+├─> Call _callAiWithLooping(generation_prompt, ...) for JSON generation
+├─> Parse generated JSON
+├─> Render to outputFormat (xlsx, docx, pdf, etc.)
+└─> RETURN AiResponse with rendered document
+```
+
+### Key Points
+
+1. **Unified Path**: All formats (txt, docx, xlsx, pdf, etc.) use the same document generation path. If `outputFormat` is not specified, it defaults to "txt".
+
+2. **User Prompt is Critical**: The prompt from `ai.process` (user's intention) is used to extract data from images, not a generic "extract all text" prompt.
+
+3. **Vision Models**: Images are processed with `IMAGE_ANALYSE` operation type, which routes to vision-capable models.
+
+4. **Text Extraction**: After vision processing, images are replaced with text ContentParts containing the extracted data.
+
+5. **JSON Structure**: All formats generate JSON structure first, then render to the target format (txt rendering extracts text from JSON structure).
+
+6. **Binary Skipping**: Binary and other non-text parts are excluded from processing.
+