# Get Merge Request Diffs — GitLab

> List the file-level changes in a merge request — each changed file's path, whether it was added, deleted or renamed, and its unified diff. This is the tool to call before reviewing, approving or commenting on a merge request: the new_path…

- Key: `gitlab-get-merge-request-diffs`
- Type: Action (Read-only)
- Version: 0.0.1
- App: GitLab (`gitlab`) — https://pipedream.com/apps/gitlab.md
- This page (HTML): https://pipedream.com/apps/gitlab/actions/get-merge-request-diffs
- Hints: read-only · open-world
- Source: https://github.com/PipedreamHQ/pipedream/blob/master/components/gitlab/actions/get-merge-request-diffs/get-merge-request-diffs.mjs

## Description

List the file-level changes in a merge request — each changed file's path, whether it was added, deleted or renamed, and its unified diff. This is the tool to call before reviewing, approving or commenting on a merge request: the `new_path` values and the line numbers inside each `diff` hunk are what **Create Merge Request Comment** and **Create Merge Request Review** need to anchor an inline comment. Large merge requests can be trimmed with **Paths** (only files under the given prefixes) and **Max Files**. Watch for `too_large: true` or `collapsed: true` on a file — GitLab omits or shortens those diffs, so do not conclude a file is unchanged. Use **Get Merge Request** for metadata and merge readiness, and **Get Merge Request Commits** for the commit history. [See the documentation](https://docs.gitlab.com/api/merge_requests/#list-merge-request-diffs)

## Props

| Prop | Type | Required | Description |
|---|---|---|---|
| `projectId` | `string` | Yes | The project, given either as its path — group/project or group/subgroup/project, e.g. backend/payments — or as its numeric project ID. The path is what appears in the project URL and is usually what a user will name, so prefer it. A pasted GitLab URL also works. Use List Projects to find the path if you only know part of the name. |
| `mergeRequestIid` | `integer` | Yes | The merge request's internal ID — the !N shown in the GitLab UI and the number at the end of the merge request URL. This is not the id field, which is a much larger instance-wide number; passing id here returns a 404. Use List Merge Requests or Search Merge Requests to resolve the IID from a title, branch or author. |
| `paths` | `string[]` | No | Return only files whose path starts with one of these prefixes, e.g. src/api/ or app/models/user.rb. Filtering happens after fetching, so this trims the response but not the number of requests. Leave blank for every changed file. |
| `maxFiles` | `integer` | No | Maximum number of changed files to return in total, paginating as needed. Defaults to 100. Lower it for a merge request that touches hundreds of files. |
| `includeDiffText` | `boolean` | No | Whether to include each file's unified diff text. Defaults to true. Set to false for a cheap list of which files changed, without the contents. |

## Run it

**MCP**

```ts
import { Client } from "@modelcontextprotocol/sdk/client/index.js"
import { StreamableHTTPClientTransport } from "@modelcontextprotocol/sdk/client/streamableHttp.js"
import { PipedreamClient } from "@pipedream/sdk"

const pd = new PipedreamClient({
  projectId: process.env.PIPEDREAM_PROJECT_ID!,
  clientId: process.env.PIPEDREAM_CLIENT_ID!,
  clientSecret: process.env.PIPEDREAM_CLIENT_SECRET!,
  projectEnvironment: "production",
})

const accessToken = await pd.rawAccessToken

const transport = new StreamableHTTPClientTransport(
  new URL("https://remote.mcp.pipedream.net/v3"),
  {
    requestInit: {
      headers: {
        Authorization: `Bearer ${accessToken}`,
        "x-pd-project-id": process.env.PIPEDREAM_PROJECT_ID!,
        "x-pd-environment": "production",
        "x-pd-external-user-id": "{external_user_id}", // any stable ID for this user in your system
        "x-pd-app-slug": "gitlab",
      },
    },
  },
)

const mcp = new Client({ name: "my-agent", version: "1.0.0" })
await mcp.connect(transport)

const { tools } = await mcp.listTools()

// listTools() hands your model this tool's input schema, so it can
// fill the arguments itself:
const result = await mcp.callTool({
  name: "gitlab-get-merge-request-diffs",
  arguments: {
    projectId: "Project",
    mergeRequestIid: 10,
  },
})
```

**TypeScript**

```ts
import { PipedreamClient } from "@pipedream/sdk"

const pd = new PipedreamClient({
  projectId: process.env.PIPEDREAM_PROJECT_ID!,
  clientId: process.env.PIPEDREAM_CLIENT_ID!,
  clientSecret: process.env.PIPEDREAM_CLIENT_SECRET!,
  projectEnvironment: "production",
})

const result = await pd.actions.run({
  id: "gitlab-get-merge-request-diffs",
  externalUserId: "{external_user_id}", // any stable ID for this user in your system
  configuredProps: {
    gitlab: { authProvisionId: "apn_xxxxxxx" },
    projectId: "Project",
    mergeRequestIid: 10,
  },
})

console.log(result)
```

**cURL**

```bash
curl -X POST https://api.pipedream.com/v1/connect/{project_id}/actions/run \
  -H "Content-Type: application/json" \
  -H "X-PD-Environment: production" \
  -H "Authorization: Bearer {access_token}" \
  -d '{
    "external_user_id": "{external_user_id}",
    "id": "gitlab-get-merge-request-diffs",
    "configured_props": {
      "gitlab": { "authProvisionId": "apn_xxxxxxx" },
      "projectId": "Project",
      "mergeRequestIid": 10
    }
  }'
```

---

- App: https://pipedream.com/apps/gitlab.md · All apps: https://pipedream.com/apps