Apply Workspace Edit

curl --request POST \
  --url https://api.example.com/tools/apply_workspace_edit

const options = {method: 'POST'};

fetch('https://api.example.com/tools/apply_workspace_edit', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.example.com/tools/apply_workspace_edit",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://api.example.com/tools/apply_workspace_edit"

	req, _ := http.NewRequest("POST", url, nil)

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

require 'uri'
require 'net/http'

url = URI("https://api.example.com/tools/apply_workspace_edit")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)

response = http.request(request)
puts response.read_body

{
  "applied": true,
  "failureReason": "<string>",
  "filesModified": 123,
  "totalEdits": 123
}

POST

tools

apply_workspace_edit

Apply Workspace Edit

curl --request POST \
  --url https://api.example.com/tools/apply_workspace_edit

const options = {method: 'POST'};

fetch('https://api.example.com/tools/apply_workspace_edit', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.example.com/tools/apply_workspace_edit",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://api.example.com/tools/apply_workspace_edit"

	req, _ := http.NewRequest("POST", url, nil)

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

require 'uri'
require 'net/http'

url = URI("https://api.example.com/tools/apply_workspace_edit")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)

response = http.request(request)
puts response.read_body

{
  "applied": true,
  "failureReason": "<string>",
  "filesModified": 123,
  "totalEdits": 123
}

Overview

Apply text changes to one or more files in your workspace. This is used to execute the edits returned by other tools like rename, format, or code actions.

Request

object

required

Workspace edit containing all changes

Show Workspace Edit

object

Map of file URIs to arrays of text edits

Show Text Edit

object

Range to replace

string

New text to insert

string

Optional description of the edit (e.g., “Rename variable”)

Response

boolean

Whether the edit was successfully applied

string

Error message if applied is false

number

Number of files that were changed

number

Total number of text edits applied

Example Request

curl -X POST https://api.pylancemcp.dev/v1/tools/call \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "apply_workspace_edit",
    "arguments": {
      "edit": {
        "changes": {
          "file:///workspace/app/utils.py": [
            {
              "range": {
                "start": {"line": 8, "character": 4},
                "end": {"line": 8, "character": 19}
              },
              "newText": "compute_total"
            }
          ]
        }
      },
      "label": "Rename function"
    }
  }'

from pylance_mcp import Client

client = Client(api_key="YOUR_API_KEY")

# Get edits from another operation (e.g., rename)
rename_result = client.rename_symbol(...)

# Apply the edits
result = client.apply_workspace_edit(
    edit=rename_result.changes,
    label="Rename calculate_total to compute_total"
)

if result.applied:
    print(f"✅ Modified {result.files_modified} files")
    print(f"   Applied {result.total_edits} edits")
else:
    print(f"❌ Failed: {result.failure_reason}")

import { PylanceMCP } from '@pylance-mcp/client';

const client = new PylanceMCP({ apiKey: 'YOUR_API_KEY' });

// Get edits from another operation
const renameResult = await client.renameSymbol(...);

// Apply the edits
const result = await client.applyWorkspaceEdit({
  edit: renameResult.changes,
  label: 'Rename calculate_total to compute_total'
});

if (result.applied) {
  console.log(`✅ Modified ${result.filesModified} files`);
  console.log(`   Applied ${result.totalEdits} edits`);
} else {
  console.log(`❌ Failed: ${result.failureReason}`);
}

import { PylanceMCP, WorkspaceEditRequest } from '@pylance-mcp/client';

const client = new PylanceMCP({ apiKey: process.env.PYLANCE_API_KEY! });

// Get edits from another operation
const renameResult = await client.renameSymbol(...);

// Apply the edits
const request: WorkspaceEditRequest = {
  edit: renameResult.changes,
  label: 'Rename calculate_total to compute_total'
};

const result = await client.applyWorkspaceEdit(request);

if (result.applied) {
  console.log(`✅ Modified ${result.filesModified} files`);
  console.log(`   Applied ${result.totalEdits} edits`);
} else {
  console.log(`❌ Failed: ${result.failureReason}`);
}

Example Response

{
  "applied": true,
  "filesModified": 3,
  "totalEdits": 12
}

Use Cases

Apply Rename Edits

# 1. Get rename edits
rename = client.rename_symbol(
    uri="file:///workspace/app/utils.py",
    line=8,
    character=4,
    new_name="compute_total"
)

# 2. Apply the edits
result = client.apply_workspace_edit(
    edit=rename.changes,
    label="Rename calculate_total to compute_total"
)

if result.applied:
    print(f"✅ Renamed across {result.files_modified} files")

Apply Format Changes

# 1. Get format edits
formatted = client.format_document(
    uri="file:///workspace/app/views.py"
)

# 2. Convert to workspace edit format
workspace_edit = {
    "file:///workspace/app/views.py": formatted.edits
}

# 3. Apply the formatting
result = client.apply_workspace_edit(
    edit=workspace_edit,
    label="Format document"
)

Apply Code Action

# 1. Get code actions
actions = client.get_code_actions(uri=file_uri, range=error_range)

# 2. Find the quickfix to apply
quickfix = next(a for a in actions.actions if a.kind == "quickfix")

# 3. Apply it
result = client.apply_workspace_edit(
    edit=quickfix.edit,
    label=quickfix.title
)

if result.applied:
    print(f"✅ Applied fix: {quickfix.title}")

Batch Multiple Edits

# Apply edits to multiple files at once
workspace_edit = {
    "file:///workspace/app/utils.py": [
        {"range": {...}, "newText": "new_name"}
    ],
    "file:///workspace/app/views.py": [
        {"range": {...}, "newText": "new_name"},
        {"range": {...}, "newText": "import new_name"}
    ],
    "file:///workspace/tests/test_utils.py": [
        {"range": {...}, "newText": "new_name"}
    ]
}

result = client.apply_workspace_edit(
    edit=workspace_edit,
    label="Update references"
)

Edit Application Order

Edits are applied in a specific order to prevent conflicts:

Sort by File

Group edits by file URI

Sort by Position

Within each file, sort edits from bottom to top (descending line/character)

Apply Edits

Apply each edit, preventing line number shifts

Verify

Confirm all edits applied successfully

Bottom-to-top ordering ensures that edits don’t affect the positions of subsequent edits.

Error Handling

The operation is atomic - either all edits succeed or none are applied:

result = client.apply_workspace_edit(edit=workspace_edit)

if not result.applied:
    if "FILE_NOT_FOUND" in result.failure_reason:
        print("❌ One or more files don't exist")
    elif "PERMISSION_DENIED" in result.failure_reason:
        print("❌ Cannot write to files")
    elif "CONFLICTING_EDITS" in result.failure_reason:
        print("❌ Edits overlap - cannot apply safely")
    else:
        print(f"❌ Failed: {result.failure_reason}")

Safety Features

Atomic Operation

All files updated together or none at all

Conflict Detection

Overlapping edits are rejected

Validation

File paths and ranges validated before applying

Rollback Support

Failed edits don’t leave partial changes

Best Practices

Preview First: Show user what will change before applying

Use Version Control: Commit before large edits so you can revert

Validate Ranges: Ensure all ranges are valid before applying

Add Labels: Always provide descriptive labels for better UX

Performance Tips

Batch Edits: Apply multiple files in one operation instead of separate calls

Non-Overlapping: Ensure edits don’t overlap for faster application

Minimize Scope: Only edit necessary files and ranges

Error Responses

Code	Reason	Solution
`FILE_NOT_FOUND`	One or more files don’t exist	Verify all file URIs
`PERMISSION_DENIED`	Cannot write to file	Check file permissions
`INVALID_RANGE`	Range out of bounds	Validate line/character positions
`CONFLICTING_EDITS`	Overlapping edits in same file	Resolve conflicts first
`FILE_MODIFIED`	File changed since edits were generated	Regenerate edits
`READONLY_FILE`	File is read-only	Remove read-only flag

Rollback

If you need to undo an edit:

# Save original content before applying
original_content = {}
for file_uri in workspace_edit.keys():
    with open(file_uri.replace('file://', ''), 'r') as f:
        original_content[file_uri] = f.read()

# Apply edit
result = client.apply_workspace_edit(edit=workspace_edit)

# If something went wrong, restore original
if not result.applied or user_wants_undo:
    for file_uri, content in original_content.items():
        with open(file_uri.replace('file://', ''), 'w') as f:
            f.write(content)

Rate Limits

Tier	Requests/Hour	Requests/Day	Max Files/Edit	Max Edits/File
Free	10	50	5	100
Hobby	250	2,500	20	500
Pro	2,500	25,000	100	5,000
Enterprise	Unlimited	Unlimited	Unlimited	Unlimited

Large workspace edits count as one request but may take longer to apply.

Rename Symbol

Generate rename edits to apply

Format Document

Generate format edits to apply

Get Code Actions

Get quick fix edits to apply

Get Diagnostics

Verify no errors after applying

Get Started

Core Concepts

Guides

API Reference

Deployment

Apply Workspace Edit

Overview

Request

Response

Example Request

Example Response

Use Cases

Apply Rename Edits

Apply Format Changes

Apply Code Action

Batch Multiple Edits

Edit Application Order

Error Handling

Safety Features

Atomic Operation

Conflict Detection

Validation

Rollback Support

Best Practices

Performance Tips

Error Responses

Rollback

Rate Limits

Rename Symbol

Format Document

Get Code Actions

Get Diagnostics

​Overview

​Request

​Response

​Example Request

​Example Response

​Use Cases

​Apply Rename Edits

​Apply Format Changes

​Apply Code Action

​Batch Multiple Edits

​Edit Application Order

​Error Handling

​Safety Features

Atomic Operation

Conflict Detection

Validation

Rollback Support

​Best Practices

​Performance Tips

​Error Responses

​Rollback

​Rate Limits

​Related Tools

Rename Symbol

Format Document

Get Code Actions

Get Diagnostics

Overview

Request

Response

Example Request

Example Response

Use Cases

Apply Rename Edits

Apply Format Changes

Apply Code Action

Batch Multiple Edits

Edit Application Order

Error Handling

Safety Features

Best Practices

Performance Tips

Error Responses

Rollback

Rate Limits

Related Tools