---
title: Suggest Code Changes in GitLab
description: "Create code suggestions in GitLab merge requests with AI. Add inline comments, multi-line suggestions, draft notes for batch reviews, and apply suggestions directly with GitLab MCP prompts."
head:
- - meta
- name: keywords
content: gitlab code suggestions, inline comments, merge request feedback, draft notes, batch review, code improvements
---
# Suggest Code Changes in GitLab
Use code suggestions to provide concrete fixes during code review. Suggestions can be applied directly from the MR interface.
## Add a Code Suggestion
> "Suggest replacing the null check with optional chaining on line 15 of `src/auth.ts` in MR !42"
> "Add a suggestion to rename the variable on line 23"
```json [Create suggestion]
{
"action": "suggest",
"project_id": "my-org/api",
"merge_request_iid": "42",
"comment": "Consider using optional chaining for cleaner null handling",
"suggestion": "const name = user?.profile?.name ?? 'Unknown';",
"position": {
"base_sha": "abc123",
"head_sha": "def456",
"start_sha": "ghi789",
"new_path": "src/auth.ts",
"new_line": 15,
"position_type": "text"
}
}
```
## Multi-Line Suggestions
> "Replace lines 10-15 with a more efficient implementation"
Use `lines_above` and `lines_below` to include surrounding context:
```json [Multi-line suggestion]
{
"action": "suggest",
"project_id": "my-org/api",
"merge_request_iid": "42",
"comment": "This can be simplified using Array.filter",
"suggestion": "const active = users.filter(u => u.isActive);\nconst names = active.map(u => u.name);",
"lines_above": 2,
"lines_below": 1,
"position": {
"base_sha": "abc123",
"head_sha": "def456",
"start_sha": "ghi789",
"new_path": "src/users.ts",
"new_line": 12,
"position_type": "text"
}
}
```
## Apply a Suggestion
> "Apply the suggestion #12345 on MR !42"
::: code-group
```json [Apply single]
{
"action": "apply_suggestion",
"project_id": "my-org/api",
"merge_request_iid": "42",
"suggestion_id": 12345,
"commit_message": "refactor(auth): use optional chaining for null safety"
}
```
```json [Apply multiple]
{
"action": "apply_suggestions",
"project_id": "my-org/api",
"merge_request_iid": "42",
"suggestion_ids": [12345, 12346, 12347],
"commit_message": "refactor(review): apply code suggestions"
}
```
:::
## Draft Notes for Batch Reviews
Use draft notes to prepare all your feedback before publishing:
> "Create a draft note on MR !42 — I'll publish all comments at once"
::: code-group
```json [Create draft]
{
"action": "create",
"project_id": "my-org/api",
"merge_request_iid": "42",
"note": "Consider extracting this into a helper function"
}
```
```json [Publish all drafts]
{
"action": "publish_all",
"project_id": "my-org/api",
"merge_request_iid": "42"
}
```
:::
## Tips
1. **Provide context** — Explain *why* the change is better, not just *what* to change
2. **Use batch suggestions** — Apply multiple suggestions in a single commit
3. **Draft first** — Use draft notes to review all feedback before publishing
4. **Be constructive** — Offer solutions, not just criticism
## Next Steps
- [Apply Feedback](/prompts/code-review/apply-feedback) — Handle suggestions on your own MRs
- [Review an MR](/prompts/code-review/review-mr) — Full review workflow
