Delete retained builds for a specific build definition in Azure DevOps.

Program.cs

using System.Net.Http.Json;

/// <summary>
/// Delete retained builds for a specific build definition in Azure DevOps.
/// </summary>
static async Task CleanRetainedBuildsAsync()
{
    // Configuration
    string organization = "my-org";
    string project = "my-proj";
    int buildDefinitionId = 1234;

    Console.WriteLine($"Cleaning retained builds for build definition {buildDefinitionId} in project {project} of organization {organization}");

    // Personal Access Token (PAT) with permissions for Build (Read & execute) and Release (Read, write & execute)
    string pat = "my-pat";

    // Setup HttpClient with basic auth (username is blank)
    var client = new HttpClient();
    client.DefaultRequestHeaders.Authorization =
        new System.Net.Http.Headers.AuthenticationHeaderValue("Basic",
        Convert.ToBase64String(System.Text.Encoding.ASCII.GetBytes($":{pat}")));

    string baseUri = $"https://dev.azure.com/{organization}/{project}";

    // Get all builds for the build definition
    string buildsUri = $"{baseUri}/_apis/build/builds?definitions={buildDefinitionId}&api-version=7.0";
    var buildsResponse = await client.GetFromJsonAsync<BuildsResponse>(buildsUri);
    if (buildsResponse is null || buildsResponse.Count == 0)
    {
        Console.WriteLine("No builds found.");
        return;
    }

    foreach (var build in buildsResponse.Value)
    {
        if (!build.RetainedByRelease)
            continue;

        Console.WriteLine($"Processing retained build: {build.Id}");

        // Get lease details for the build
        string leaseDetailsUri = $"{baseUri}/_apis/build/builds/{build.Id}/leases?api-version=7.1";
        var leaseResponse = await client.GetFromJsonAsync<LeaseResponse>(leaseDetailsUri);
        if (leaseResponse?.Count > 0)
        {
            foreach (var lease in leaseResponse.Value)
            {
                Console.WriteLine($"Deleting lease {lease.LeaseId} for build {build.Id}");
                string deleteLeaseUri = $"{baseUri}/_apis/build/retention/leases?ids={lease.LeaseId}&api-version=7.1";
                var deleteLeaseResult = await client.DeleteAsync(deleteLeaseUri);
                if (!deleteLeaseResult.IsSuccessStatusCode)
                {
                    Console.WriteLine($"Failed to delete lease {lease.LeaseId} for build {build.Id}: {deleteLeaseResult.StatusCode}");
                }
            }
        }

        // Now delete the build
        Console.WriteLine($"Deleting build {build.Id}");
        string deleteBuildUri = $"{baseUri}/_apis/build/builds/{build.Id}?api-version=7.1";
        var deleteBuildResult = await client.DeleteAsync(deleteBuildUri);
        if (!deleteBuildResult.IsSuccessStatusCode)
        {
            Console.WriteLine($"Failed to delete build {build.Id}: {deleteBuildResult.StatusCode}");
        }
    }
}

await CleanRetainedBuildsAsync();

record Build(int Id, bool RetainedByRelease);
record BuildsResponse(int Count, List<Build> Value);
record Lease(int LeaseId);
record LeaseResponse(int Count, List<Lease> Value);