Crafting a Release Pipeline json to use as template

How about this:

{
  "name": "My Release Pipeline",
  "description": "Created via API",
  "environments": [
    {
      "name": "PROD",
      "deployPhases": [
        {
          "phaseType": "agentBasedDeployment",
          "name": "Run Tasks",
          "workflowTasks": [
            {
              "name": "Download Build Artifacts",
              "taskId": "6d15af64-176c-496d-b583-fd2ae21d4df4",
              "version": "1.*",
              "inputs": {
                "buildType": "specific",
                "project": "your-project-id",
                "definition": "your-build-definition-id"
              }
            },
            {
              "name": "Azure App Service Deploy",
              "taskId": "d2d5f1c2-3b5e-4b5b-9c1f-1b3f3f3f3f3f",
              "version": "4.*",
              "inputs": {
                "ConnectionType": "AzureRM",
                "WebAppName": "your-app-name"
              }
            }
          ],
          "deploymentInput": {
            "queueId": 123,  // Agent Pool ID
            "parallelExecution": {
              "parallelExecutionType": "none"
            }
          }
        }
      ]
    }
  ],
  "variables": {
    "myVar": {
      "value": "someValue"
    }
  },
  "artifacts": [
    {
      "type": "Build",
      "definitionReference": {
        "project": {
          "id": "your-project-id"
        },
        "definition": {
          "id": "your-build-definition-id"
        }
      }
    }
  ]
}