IDE Diagnostics and Navigation Expert

Master IDE integration tools for diagnostics, code navigation, and automated fixes.

Available IDE Tools

1. Get Diagnostics (mcp__ide__getDiagnostics)

Purpose: Retrieve errors, warnings, and info messages from the IDE's language server.

When to use:

• Before fixing TypeScript/JavaScript errors
• Checking for linting violations
• Validating code changes
• Identifying compilation issues

Usage:

Use mcp__ide__getDiagnostics to get all diagnostics

Output: List of diagnostics with:

• File path
• Line and column numbers
• Severity (error/warning/info)
• Error message
• Error code (e.g., TS2304, @typescript-eslint/no-unused-vars)

Best practices:

• Always check diagnostics before claiming code is error-free
• Use this instead of running tsc --noEmit or manual compilation
• Filter by severity if only interested in errors
• Group diagnostics by file for systematic fixing

2. Find References (mcp__ide__get_references)

Purpose: Find all usages of a symbol (variable, function, class, etc.)

When to use:

• Before renaming or refactoring
• Understanding code impact
• Finding all callers of a function
• Checking if code is unused

Usage:

Use mcp__ide__get_references for symbol at file:line:column

Best practices:

• Use before making changes to understand impact
• Verify all references when refactoring
• Check for unused code (0 references)

3. Rename Symbol (mcp__ide__rename_symbol)

Purpose: Safely rename variables, functions, classes across the entire codebase

When to use:

• Renaming variables, functions, classes
• Ensuring all references are updated
• Avoiding manual find-replace errors

Usage:

Use mcp__ide__rename_symbol at file:line:column to newName

Best practices:

• ALWAYS use this instead of manual find-replace
• Safer than Edit tool for renaming (handles scope correctly)
• Automatically updates all references
• Works across files

4. Execute IDE Command (mcp__ide__execute_command)

Purpose: Execute IDE commands like auto-fix, organize imports, format document

Common commands:

Auto-fix All Issues

Use mcp__ide__execute_command with command: "editor.action.fixAll"

Use cases:

• Auto-fix ESLint violations
• Auto-fix TypeScript quick fixes
• Apply all available code actions

Organize Imports

Use mcp__ide__execute_command with command: "editor.action.organizeImports"

Use cases:

• Remove unused imports
• Sort imports
• Clean up import statements

Format Document

Use mcp__ide__execute_command with command: "editor.action.formatDocument"

Best practices:

• Use editor.action.fixAll instead of running eslint --fix via Bash
• More efficient than manual fixes
• Respects IDE configuration
• Works with all language servers

Diagnostic Severity Levels

1. Error (must fix):

   • TypeScript type errors
   • Syntax errors
   • Missing imports
   • Breaking compilation

2. Warning (should fix):

   • Unused variables
   • Deprecated API usage
   • Potential bugs
   • Style violations (if configured as warnings)

3. Info (consider fixing):

   • Suggestions
   • Code improvements
   • Style preferences

Common Diagnostic Patterns

TypeScript Errors

Missing imports:

Error: Cannot find name 'foo'
Code: TS2304
Fix: Add import statement

Type mismatches:

Error: Type 'string' is not assignable to type 'number'
Code: TS2322
Fix: Convert type or adjust declaration

Property errors:

Error: Property 'bar' does not exist on type 'Foo'
Code: TS2339
Fix: Add property or check type definition

ESLint Errors

Unused variables:

Error: 'foo' is defined but never used
Rule: @typescript-eslint/no-unused-vars
Fix: Remove variable or use it

Missing return types:

Error: Missing return type on function
Rule: @typescript-eslint/explicit-function-return-type
Fix: Add explicit return type annotation

Workflow: Fix All Diagnostics

Step 1: Get Current Diagnostics

Use mcp__ide__getDiagnostics

Step 2: Prioritize Fixes

1. Fix errors first (severity: error)
2. Then warnings
3. Then info-level suggestions

Step 3: Fix Systematically

• Group by file
• Fix one file at a time
• Use editor.action.fixAll for auto-fixable issues
• Manually fix remaining issues with Edit tool

Step 4: Verify

Use mcp__ide__getDiagnostics again to confirm all fixed

Step 5: Iterate

Repeat until no diagnostics remain

Best Practices

DO:

• ✅ Use mcp__ide__getDiagnostics instead of tsc --noEmit
• ✅ Use mcp__ide__rename_symbol instead of manual find-replace
• ✅ Use editor.action.fixAll instead of eslint --fix
• ✅ Check diagnostics before committing changes
• ✅ Fix errors before warnings
• ✅ Read file context before fixing (use Read tool)

DON'T:

• ❌ Don't run tsc --noEmit via Bash when you have getDiagnostics
• ❌ Don't use Edit tool for renaming (use rename_symbol)
• ❌ Don't ignore warnings - they often indicate real issues
• ❌ Don't fix diagnostics without understanding the context

Integration with Other Tools

With Read Tool

Always read the file before fixing diagnostics to understand context:

1. Use Read to view the file
2. Understand the code
3. Fix diagnostics appropriately

With Edit Tool

After understanding diagnostics, use Edit to make targeted fixes:

1. Get diagnostics
2. Read file
3. Plan fixes
4. Apply edits
5. Verify with getDiagnostics

With Glob Tool

For project-wide issues, find affected files first:

1. Use Glob to find TypeScript files: **/*.ts
2. Get diagnostics
3. Fix systematically

Troubleshooting

No Diagnostics Returned

Possible causes:

• IDE not running or not connected
• File not opened in IDE
• Language server not initialized

Diagnostics Not Updating

After fixes, diagnostics may take a moment to refresh. If needed, trigger a refresh by:

• Using editor.action.fixAll
• Saving the file
• Re-running getDiagnostics

References

• VS Code Commands: Use /ide for interactive IDE features
• TypeScript Error Codes: https://typescript.tv/errors/
• ESLint Rules: https://eslint.org/docs/rules/