Custom Instructions
Write your own AI prompts to control exactly how files are named with specialized extraction rules.
Custom Instructions let you write your own AI prompts to control exactly how files are named. Instead of the default RenameClick prompt that generates descriptive filenames, you can define specific extraction rules for your document types.

How It Works
- Open the Prompt Selector in the workspace header
- Click Create Custom Instructions to open the prompt editor
- Write your custom instructions
- Save — the new prompt is auto-selected immediately
- Drop files — AI follows your custom instructions instead of the default

What Custom Instructions Control
Custom instructions define the filename output only. They tell the AI what information to extract and how to format the filename.
Categorization still uses the actual file content, not the generated filename. The category decision is independent of your custom prompt.
When Custom Prompt Is Active
When you select a custom prompt:
- Format selector is disabled — your prompt controls the final filename structure
- Output Language selector is disabled — your prompt controls the language
- Both are re-enabled when you switch back to the default RenameClick prompt
This applies in both the Rename Workspace and in Auto Flow row settings.
Prompt Constraints
| Setting | Default | Range |
|---|---|---|
| Max prompt length | 1,800 characters | 500 — 4,000 (configurable in Local AI Settings) |
Example: Electricity Bill Extraction
Result: Electricity Bill__2024-03-15__317,03__John Smith.pdf
Example: Medical Report Naming
Result: Lab Results - John Smith - 2025-01-20.pdf
Example: Invoice Processing
Result: Acme Corp_INV-2024-0847_2024-11-15.pdf
Example: Photo Event Naming
Result: Birthday Party Cake Cutting.jpg
Best Practices
- Be specific about output format — Tell the AI exactly what format you want. Show an example.
- Handle missing data — Include rules for what to do when information isn't found (e.g., "use UNKNOWN")
- Keep it focused — One clear task per prompt works better than complex multi-step instructions
- Test with sample files — Drop a few representative files to verify results before batch processing
- Use separators — Underscores
_or hyphens-make structured filenames readable
Custom Instructions + Categorization
You can use custom instructions and categorization together, but be aware:
- The custom prompt controls the filename only
- Categorization uses the actual file content to decide which folder
- These are independent decisions
For best category accuracy with a specialized prompt, use a two-step workflow:
- First pass: Rename only (with your custom prompt)
- Second pass: Categorize only (AI reads file content fresh)
Auto Flow Integration
Each Auto Flow row can have its own custom prompt:
- Row 1 can use an invoice extraction prompt
- Row 2 can use a medical document prompt
- Row 3 can use the default RenameClick prompt
Configure per-row prompts in the row's settings panel.