# Compare dependencies

> Compare the dependencies at two commits, branches or tags (basehead, as base...head): what was added and removed per lockfile, with the known vulnerabilities of what was added and whether it passes the repository's dependency review policy.

<div class="g1t-endpoint"><span class="g1t-method" data-method="get">GET</span><code>/repos/{owner}/{name}/dependency-graph/compare/{basehead}</code></div>

Needs the g1t plan on a private repository.

- **Authentication:** Required. Send an [access token](/reference/api/#authentication) as `Authorization: Bearer`.
- **MCP tool:** [`security`](/reference/mcp/#security) with `action` `compare_dependencies`, and the same inputs
- **Scope:** An access token needs [`security:read`](/guides/authentication/#scopes).

## Path parameters

| Name | Type | Required | Description |
| --- | --- | --- | --- |
| `owner` | string | Yes | The workspace that owns the repository. |
| `name` | string | Yes | The repository's name. |
| `basehead` | string | Yes | base...head: two commits, branches or tags, e.g. main...my-branch. |

## Example request

```sh
curl https://api.g1t.sh/repos/flagon-io/hello/dependency-graph/compare/main...upgrade-deps \
  -H "Authorization: Bearer $G1T_TOKEN"
```

## Example response

A successful request answers `200` with:

```json
{
  "base": "main",
  "head": "upgrade-deps",
  "changes": [
    {
      "change_type": "added",
      "manifest": "package-lock.json",
      "ecosystem": "npm",
      "name": "lodash",
      "version": "4.17.20",
      "relationship": "direct",
      "development": false,
      "license": "MIT",
      "purl": "pkg:npm/lodash@4.17.20",
      "vulnerabilities": [
        {
          "advisory": "GHSA-35jh-r3h4-6jhm",
          "osv_id": "GHSA-35jh-r3h4-6jhm",
          "summary": "Command Injection in lodash",
          "severity": "high",
          "fixed_version": "4.17.21",
          "url": "https://osv.dev/vulnerability/GHSA-35jh-r3h4-6jhm"
        }
      ],
      "denied_license": false,
      "failing": true
    },
    {
      "change_type": "removed",
      "manifest": "package-lock.json",
      "ecosystem": "npm",
      "name": "lodash",
      "version": "4.17.21",
      "relationship": "direct",
      "development": false,
      "license": "MIT",
      "purl": "pkg:npm/lodash@4.17.21",
      "vulnerabilities": [],
      "denied_license": false,
      "failing": false
    }
  ],
  "passed": false,
  "headline": "Adds 1 vulnerable package",
  "fail_on": "high",
  "deny_licenses": []
}
```

## Errors

A failed request answers with one of these statuses and a body like `{"error": {"code": "not_found", "message": "Repository not found."}}`. See [errors](/reference/api/#errors).

| Status | Code | When |
| --- | --- | --- |
| 401 | `unauthenticated` | A token is required, or the one sent is not valid. |
| 403 | `forbidden` | The token is valid but not allowed to do this, such as a member-only change or an agent token outside its repository. |
| 404 | `not_found` | It does not exist, or you cannot see it. |
| 422 | `invalid` | The input is not valid. `message` says which field and why. |