write_to_file

The write_to_file tool is used to create new files or completely replace the content of existing files through an interactive confirmation process. It provides a diff view, allowing users to review content before changes take effect.

Parameter Description

This tool accepts the following parameters, all of which are required:

• path (Path): Path to the file to be written, relative to the current working directory
• content (Content): Complete content to be written to the file
• line_count (Line Count): Total number of lines in the file, including empty lines

Core Functions

This tool writes the specified content to the target file: if the file does not exist, it creates it; if the file already exists, it completely overwrites the original content. All content changes must be explicitly confirmed by the user through the diff view interface, and users can review or even edit the proposed changes before they take effect.

Applicable Scenarios

• When VJSP needs to create files from scratch
• When VJSP needs to completely rewrite existing files
• When batch creating multiple files for new projects
• When generating configuration files, technical documentation, or source code
• When content review and confirmation are required before changes take effect

Core Features

• Interactive Confirmation: Displays proposed changes in a diff view, requiring explicit user confirmation before changes take effect
• User Edit Support: Allows users to edit and modify the proposed content before final confirmation
• Security Protection Mechanisms: Detects code omissions, verifies file path validity, and prevents content truncation
• Editor Integration: When opening the diff view, automatically scrolls to the first content difference location
• Content Preprocessing: Compatible with output results from different AI models, automatically cleans redundant content identifiers
• Access Control: Before executing changes, verifies file access restriction rules configured in .vjspignore
• Automatic Parent Directory Creation: Automatically creates required parent directories using system dependencies
• Complete Replacement: Generates the target file with complete content conversion in a single operation

Limitations

• Not suitable for partial modification of existing files: Compared to the apply_diff tool, it is less efficient and takes longer when modifying existing files
• Performance degradation with large files: Execution efficiency decreases significantly when handling large files
• Complete overwrite mechanism: Replaces all original content of the file and cannot retain specified original content
• Strong dependency on line count parameter: Requires accurate file line count to be passed to detect content truncation risks
• Additional overhead from review process: Compared to direct editing, the interactive confirmation process adds extra operational steps
• Only supports interactive execution: Cannot be used in automated workflows that require non-interactive operation

Execution Process

After calling the write_to_file tool, operations are executed in the following steps:

1. Parameter Validation: Validates the completeness of required parameters and operation permissions

   • Checks if path, content, and line_count parameters are all passed
   • Validates whether the target file is accessible (not restricted by .vjspignore configuration)
   • Ensures the file path is within the valid boundaries of the workspace
   • Counts the number of consecutive errors due to missing parameters
   • Displays dedicated error messages for different validation failure scenarios

2. Content Preprocessing

   • Removes code block identifiers that may be added by AI models
   • Processes escaped HTML entities (mainly for outputs from non-Claude series models)
   • Automatically strips line numbers if they are accidentally included in the content
   • Executes dedicated content preprocessing logic for models from different AI service providers

3. Diff View Generation

   • Opens a diff view in the editor to display proposed content changes
   • Adds a 300ms delay to ensure interface responsiveness
   • Automatically scrolls to the position of the first content difference
   • Highlights changed content to improve review efficiency

4. User Confirmation Process

   • Blocks the execution process, waiting for explicit confirmation from the user
   • Supports direct editing of proposed content by the user in the diff view
   • Captures all user editing operations as part of the final written content
   • Provides a change rejection option, allowing users to abandon the current operation
   • Detects and merges user modifications to generate the final content to be written

5. Security Validation

   • Compares the passed line_count parameter with the actual number of content lines to detect content truncation risks
   • Immediately displays warning messages if incomplete content is detected
   • Re-validates the legitimacy of the file path and operation access permissions
   • Specifically validates whether the file exceeds workspace boundaries through the isOutsideWorkspace flag

6. File Writing

   • Writes the user-confirmed content (including user-edited parts) to the target file
   • Outputs a confirmation message for successful operation
   • Resets the counter for consecutive errors due to missing parameters after successful operation execution

Practical Application Examples

• When creating a new project, VJSP batch generates various project files and allows users to review and confirm each one before submitting changes
• During configuration file initialization, VJSP displays the proposed configuration content in a diff view for user confirmation
• When generating technical documentation, VJSP creates Markdown format documentation files and supports users in completing final content adjustments in the diff view
• During the prototype development phase, VJSP displays complete source code files in the diff view, allowing users to perform fine-tuning before saving

Usage Examples

Create a new JSON configuration file

<write_to_file>
<path>config/settings.json</path>
<content>
{
  "apiEndpoint": "https://api.example.com",
  "theme": {
    "primaryColor": "#007bff",
    "secondaryColor": "#6c757d",
    "fontFamily": "Arial, sans-serif"
  },
  "features": {
    "darkMode": true,
    "notifications": true,
    "analytics": false
  },
  "version": "1.0.0"
}
</content>
<line_count>14</line_count>
</write_to_file>

Create a simple HTML file

<write_to_file>
<path>src/index.html</path>
<content>
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>My Application</title>
  <link rel="stylesheet" href="styles.css">
</head>
<body>
  <div id="app"></div>
  <script src="app.js"></script>
</body>
</html>
</content>
<line_count>13</line_count>
</write_to_file>

Create a new JavaScript module file

<write_to_file>
<path>src/utils/helpers.js</path>
<content>
/**
 * Application general utility function library
 */

export function formatDate(date) {
  return new Date(date).toLocaleDateString();
}

export function calculateTotal(items) {
  return items.reduce((sum, item) => sum + item.price, 0);
}

export function debounce(func, delay) {
  let timeout;
  return function(...args) {
    clearTimeout(timeout);
    timeout = setTimeout(() => func.apply(this, args), delay);
  };
}
</content>
<line_count>18</line_count>
</write_to_file>