# update_note
Update an existing note in the Obsidian vault.
## Description
Replaces the content of an existing note. Optionally creates the note if it doesn't exist when `createIfNotExists` is set to `true`.
## Parameters
| Parameter | Type | Required | Default | Description |
| ------------------- | --------- | -------- | ------- | ------------------------------------------------- |
| `path` | `string` | Yes | - | Path to the note within the vault |
| `content` | `string` | Yes | - | New content for the note |
| `createIfNotExists` | `boolean` | No | `false` | Create note and directories if file doesn't exist |
## Returns
Success message confirming the update.
```json
{
"content": [
{
"type": "text",
"text": "Note updated successfully at notes/meeting.md"
}
]
}
```
## Examples
### Update an existing note
```json
{
"name": "update_note",
"arguments": {
"path": "notes/meeting.md",
"content": "# Updated Meeting Notes\n\nNew content here."
}
}
```
### Create or update (upsert)
```json
{
"name": "update_note",
"arguments": {
"path": "new-folder/new-note.md",
"content": "# New Note\n\nThis creates the note if it doesn't exist.",
"createIfNotExists": true
}
}
```
## Behavior
```mermaid
flowchart TD
A[update_note called] --> B{File exists?}
B -->|Yes| C[Write new content]
B -->|No| D{createIfNotExists?}
D -->|Yes| E[Create directories]
D -->|No| F[Fail: Not found]
E --> G[Write new file]
C --> H[Invalidate content cache]
G --> I[Invalidate file list cache]
I --> H
H --> J[Invalidate search cache]
J --> K[Update inverted index]
K --> L[Return success]
```
### With createIfNotExists: false (default)
- Updates existing files
- Fails if file doesn't exist
- Fails if directory doesn't exist
### With createIfNotExists: true
- Updates existing files
- Creates file if it doesn't exist
- Creates missing directories automatically
### Cache Invalidation
After updating a note:
1. Content cache entry for the file is invalidated
2. Search result cache is cleared
3. Inverted index entry is invalidated (for re-indexing on next read)
## Error Handling
| Error | Cause |
| --------------------------------- | ---------------------------------------------- |
| `"Path and content are required"` | Missing required parameters |
| `"Note not found: {path}"` | File doesn't exist and createIfNotExists=false |
| `EACCES` | Permission denied |
## Quick Reference
| Operation | File Exists | File Doesn't Exist | Missing Directories | Result |
| ------------------------------------- | ----------- | ------------------ | ------------------- | ------- |
| update_note (default) | Updates | Fails | Fails | Error |
| update_note (createIfNotExists: true) | Updates | Creates file | Creates dirs | Success |
## Related Tools
- [create_note](create_note.md) - Create-only operation
- [read_note](read_note.md) - Read the note content
- [delete_note](delete_note.md) - Delete the note
## Source
- Handler: [`src/handlers/toolHandlers.ts`](../../src/handlers/toolHandlers.ts)
- Service: [`src/services/fileSystem.ts`](../../src/services/fileSystem.ts)
