glab-mr

name	glab-mr
description	Create, view, manage, approve, and merge GitLab merge requests. Use when working with MRs: creating from branches/issues, reviewing, approving, adding comments, resolving discussion threads, checking out locally, viewing diffs, rebasing, merging, or managing state. Triggers on merge request, MR, pull request, PR, review, approve, merge, resolve thread.

glab mr

Create, view, and manage GitLab merge requests.

Quick start

# Create MR from current branch
glab mr create --fill

# List my MRs
glab mr list --assignee=@me

# Review an MR
glab mr checkout 123
glab mr diff
glab mr approve

# Merge an MR
glab mr merge 123 --when-pipeline-succeeds --remove-source-branch

Common workflows

Creating MRs

From current branch:

glab mr create --fill --label bugfix --assignee @reviewer

# Create now, merge automatically when checks pass
glab mr create --fill --auto-merge

# Start from an MR template file when your project uses one
glab mr create --fill --template .gitlab/merge_request_templates/default.md

From issue:

glab mr for 456  # Creates MR linked to issue #456

Draft MR:

glab mr create --draft --title "WIP: Feature X"

Review workflow

1. List pending reviews:

   glab mr list --reviewer=@me --state=opened
   

2. Checkout and test:

   glab mr checkout 123
   npm test
   

3. Leave feedback:

   # Forward command surface for new MR comments/discussions
   glab mr note create 123 -m "Looks good, one question about the cache logic"
   
   # Automation/status update that should not create a resolvable thread
   glab mr note create 123 -m "Build status: green" --resolvable=false
   
   # Reply inside an existing discussion thread
   glab mr note create 123 --reply abc12345 -m "Good catch — updated"
   
   # Native diff comments on the latest MR version
   glab mr note create 123 --file src/cache.ts --line 42 -m "Please extract this branch"
   glab mr note create 123 --file src/cache.ts --old-line 17 -m "Why was this removed?"
   
   # List discussion threads on the MR (experimental)
   glab mr note list 123
   
   # Resolve or reopen a discussion by note/discussion ID (experimental)
   glab mr note resolve 3107030349 123
   glab mr note reopen 3107030349 123
   

4. Approve:

   glab mr approve 123
   

Automated review workflow:

For repetitive review tasks, use the automation script bundled with this skill under scripts/ (paths below are relative to the skill's own directory):

scripts/mr-review-workflow.sh 123
scripts/mr-review-workflow.sh 123 "pnpm test"

This automatically: checks out → runs tests → posts result → approves if passed.

Merge strategies

Auto-merge when pipeline passes:

glab mr merge 123 --when-pipeline-succeeds --remove-source-branch

Squash commits:

glab mr merge 123 --squash

Rebase before merge:

glab mr rebase 123
glab mr merge 123

Troubleshooting

Merge conflicts:

• Checkout MR: glab mr checkout 123
• Resolve conflicts manually in your editor
• Commit resolution: git add . && git commit
• Push: git push

Cannot approve MR:

• Check if you're the author (can't self-approve in most configs)
• Verify permissions: glab mr approvers 123
• Ensure MR is not in draft state

Pipeline required but not running:

• Check .gitlab-ci.yml exists in branch
• Verify CI/CD is enabled for project
• Trigger manually: glab ci run

"MR already exists" error:

• List existing MRs from branch: glab mr list --source-branch <branch>
• Close old MR if obsolete: glab mr close <id>
• Or update existing: glab mr update <id> --title "New title"

Related Skills

Working with issues:

• See glab-issue for creating/managing issues
• Use glab mr for <issue-id> to create MR linked to issue
• Script: scripts/create-mr-from-issue.sh automates branch + MR creation

CI/CD integration:

• See glab-ci for pipeline status before merging
• Use glab mr create --auto-merge to request auto-merge up front, or glab mr merge --when-pipeline-succeeds on an existing MR

Automation:

• Script: scripts/mr-review-workflow.sh for automated review + test workflow

Native MR note flow (glab mr note create)

glab mr note create is the preferred command surface for posting new MR discussions.

Use native glab mr note create when

# New top-level discussion/comment
glab mr note create 123 -m "Please add a regression test"

# Non-resolvable note for automation/status output
glab mr note create 123 -m "Build status: green" --resolvable=false

# Reply to an existing discussion thread
glab mr note create 123 --reply abc12345 -m "Fixed in the latest push"

# File-level diff comment
glab mr note create 123 --file src/app.ts -m "General concern on this file"

# Line comment on the new side of the diff
glab mr note create 123 --file src/app.ts --line 84 -m "This branch can return null"

# Range comment on the new side
glab mr note create 123 --file src/app.ts --line 84:96 -m "Consider extracting this block"

# Comment on a removed line from the old side
glab mr note create 123 --file src/app.ts --old-line 37 -m "Why was this guard removed?"

Flag rules worth remembering from the upstream help/docs:

• --reply targets an existing discussion thread instead of starting a new one.
• --reply accepts a full discussion ID or a unique prefix of at least 8 characters.
• By default, new top-level notes are created as resolvable discussion threads. Use --resolvable=false for bot/status comments that should not block projects requiring all threads to be resolved.
• --line and --old-line require --file and cannot be used together.
• --file, --reply, and --unique are mutually exclusive.
• --resolvable=false cannot be combined with --reply, --file, --line, or --old-line.
• Omit both --line and --old-line when you want a file-level diff comment.

Keep the helper/script path when

Use the bundled inline-comment helper or raw glab api JSON-body approach when you need stronger anchoring guarantees for automation, especially when:

• you must verify that GitLab created an actual inline discussion rather than silently falling back to a general MR note
• you are posting many comments in batch
• you are targeting tricky diffs (new files, renamed files, complex paths, or line-code fallback cases)

glab mr note create is now enough for most interactive reply and diff-comment workflows. The helper remains valuable for robust automated review pipelines.

Posting Inline Comments on MR Diffs

The glab api --field Problem

glab api --field position[new_line]=N silently falls back to a general (non-inline) comment when GitLab rejects the position data. This happens with:

• Entirely new files (new_file: true in the diff)
• Files with complex/encoded paths
• Any nested position field that doesn't survive form encoding

There is no error — GitLab just drops the position and creates a general discussion. You won't know it failed unless you check the returned note's position field.

The Fix: Always Use JSON Body

Post inline comments via the REST API with a Content-Type: application/json body:

import json, urllib.request, urllib.parse, subprocess

# Get token from glab config
token = subprocess.run(
    ["glab", "config", "get", "token", "--host", "gitlab.com"],
    capture_output=True, text=True
).stdout.strip()

project = urllib.parse.quote("mygroup/myproject", safe="")
mr_iid = 42

# Always fetch fresh SHAs — never use cached values
r = urllib.request.urlopen(urllib.request.Request(
    f"https://gitlab.com/api/v4/projects/{project}/merge_requests/{mr_iid}/versions",
    headers={"PRIVATE-TOKEN": token}
))
v = json.loads(r.read())[0]

payload = {
    "body": "Your comment here",
    "position": {
        "base_sha":  v["base_commit_sha"],
        "start_sha": v["start_commit_sha"],
        "head_sha":  v["head_commit_sha"],
        "position_type": "text",
        "new_path": "src/utils/helpers.ts",
        "new_line": 16,
        "old_path": "src/utils/helpers.ts",  # for renamed files, use the diff's actual old_path
        "old_line": None                       # None = added line
    }
}

req = urllib.request.Request(
    f"https://gitlab.com/api/v4/projects/{project}/merge_requests/{mr_iid}/discussions",
    data=json.dumps(payload).encode(),
    headers={"PRIVATE-TOKEN": token, "Content-Type": "application/json"},
    method="POST"
)
with urllib.request.urlopen(req) as resp:
    result = json.loads(resp.read())
    note = result["notes"][0]
    is_inline = note.get("position") is not None  # True = inline, False = fell back to general
    print("inline:", is_inline, "| disc_id:", result["id"])

Finding the Correct Line Number

Line numbers must point to an added line (+ prefix) in the diff — context lines and removed lines will cause the position to be rejected:

import re

def get_new_line_number(diff_text, keyword):
    """Find the new_file line number of the first added line containing keyword."""
    new_line = 0
    for line in diff_text.split("\n"):
        hunk = re.match(r"@@ -\d+(?:,\d+)? \+(\d+)(?:,\d+)? @@", line)
        if hunk:
            new_line = int(hunk.group(1)) - 1
            continue
        if line.startswith("-") or line.startswith("\\"):
            continue
        new_line += 1
        if line.startswith("+") and keyword in line:
            return new_line
    return None

# Usage
diffs = json.loads(...)  # from /merge_requests/{iid}/diffs
for d in diffs:
    if d["new_path"] == "src/utils/helpers.ts":
        line = get_new_line_number(d["diff"], "safeParse")
        print("line:", line)

Reusable Script

For scripted or automated MR reviews, use the helper bundled with this skill under scripts/ (paths below are relative to the skill's own directory):

# Single comment
python3 scripts/post-inline-comment.py \
  --project "mygroup/myproject" \
  --mr 42 \
  --file "src/utils/helpers.ts" \
  --line 16 \
  --body "This returns the wrapper object — use .data instead."

# Batch from JSON file
python3 scripts/post-inline-comment.py \
  --project "mygroup/myproject" \
  --mr 42 \
  --batch comments.json

Batch file format:

[
  { "file": "src/utils/helpers.ts", "line": 16, "body": "Comment 1" },
  { "file": "src/routes/+page.svelte", "line": 58, "body": "Comment 2" }
]

The script auto-reads your token from glab config, fetches fresh SHAs and diffs, and uses a two-step anchoring strategy:

1. Try the normal position[new_line] inline payload first.
2. If GitLab rejects it with a line_code validation error, compute the diff anchor and retry with position[line_range][start/end][line_code].

That retry path is the preferred recovery for failures like:

• 400 Bad request - Note {:line_code=>["can't be blank", "must be a valid line code"]}

Only if that retry also fails should your broader review workflow fall back to a root MR note that clearly says inline anchoring failed while preserving the exact finding text and reviewer identity.

---

Filtering discussion threads by resolution

# Show only unresolved discussion threads on an MR
glab mr view 123 --unresolved

# Show only resolved threads
glab mr view 123 --resolved

Useful for quickly checking which review threads still need attention before merging.

glab mr list filtering flags

glab mr list supports the following filtering and sorting flags:

# Filter by author
glab mr list --author <username>

# Filter by source or target branch
glab mr list --source-branch feature/my-branch
glab mr list --target-branch main

# Filter by draft status
glab mr list --draft
glab mr list --not-draft

# Filter by label or exclude label
glab mr list --label bugfix
glab mr list --not-label wip

# Order and sort
glab mr list --order updated_at --sort desc
glab mr list --order merged_at --sort asc

# Date range filtering
glab mr list --created-after 2026-01-01
glab mr list --created-before 2026-03-01

# Search in title/description
glab mr list --search "login fix"

# Full flag reference (all available flags)
glab mr list \
  --assignee @me \
  --author vince \
  --reviewer @me \
  --label bugfix \
  --not-label wip \
  --source-branch feature/x \
  --target-branch main \
  --milestone "v2.0" \
  --draft \
  --state opened \
  --order updated_at \
  --sort desc \
  --search "auth" \
  --created-after 2026-01-01

Structured output

glab mr approvers supports --output json / -F json for structured output, which is useful for agent automation.

# View MR approvers with JSON output
glab mr approvers 123 --output json
glab mr approvers 123 -F json

Command reference

For complete command documentation and all flags, see references/commands.md.

Available commands:

• approve - Approve merge requests
• checkout - Check out an MR locally
• close - Close merge request
• create - Create new MR
• delete - Delete merge request
• diff - View changes in MR
• for - Create MR for an issue
• list - List merge requests
• merge - Merge/accept MR
• note - MR discussion commands; use glab mr note create for new comments, plus list, resolve, and reopen
• rebase - Rebase source branch
• reopen - Reopen merge request
• revoke - Revoke approval
• subscribe / unsubscribe - Manage notifications
• todo - Add to-do item
• update - Update MR metadata
• view - Display MR details