Update README with some documentation

README.md

@@ -1,5 +1,93 @@
+## Introduction
 
-# Contributing
+This chart bootstraps a [Visual Studio Team Services agent pool](https://github.com/Microsoft/vsts-agent) on a [Kubernetes](http://kubernetes.io) cluster using the [Helm](https://helm.sh) package manager.
+
+## Prerequisites
+ - Kubernetes 1.8+ or newer
+
+## Configuration
+
+The following tables lists the configurable parameters of the `vsts-agent` chart and their default values.
+
+| Parameter                         | Description                           | Default                                                   |
+| --------------------------------- | ------------------------------------- | --------------------------------------------------------- |
+| `image.repository`                | vsts-agent image                      | `microsoft/vsts-agent`                                    |
+| `image.tag`                       | Specify image tag                     | `latest`                                                  |
+| `image.pullSecrets`               | Specify image pull secrets            | `nil` (does not add image pull secrets to deployed pods)  |
+| `image.pullPolicy`                | Image pull policy                     | `Always`                                                  |
+| `replicas`                        | Number of vsts-agent instaces started | `3`                                                       |
+| `resources.disk`                  | Size of the disk attached to the agent| `50Gi`                                                    |
+| `vstsAccount`                     | VSTS account name                     | `nil` (must be provided during installation)              |
+| `vstsToken`                       | VSTS personal access token            | `nil` (must be provided during installation)              |
+| `vstsPool`                        | VSTS agent pool name                  | `kubernetes-vsts-agents`                                  |
+| `vstsAgentName`                   | VSTS agent name                       | `$HOSTNAME`                                               |
+| `vstsWorkspace`                   | VSTS agent workspace                  | `/workspace`                                              |
+
+## Configure your VSTS instance
+
+Before starting the chart installation, you have to configure your VSTS instance as follows:
+
+1. Create a personal access token with the authorized scope **Agent Pools(read, manage)**  following these [instructions](https://docs.microsoft.com/en-us/vsts/git/_shared/personal-access-tokens). You will have to provide later the base64 encoded value of this token to the `vstsToken` value of the chart.
+
+2. Create a new queue and agent pool with the name `kubernetes-vsts-agents`. You can find more details [here](https://docs.microsoft.com/en-us/vsts/build-release/concepts/agents/pools-queues#creating-agent-pools-and-queues).
+
+## Installing the Chart
+
+The chart can be installed with the following command:
+
+```bash
+export VSTS_TOKEN=$(echo -n '<VSTS TOKEN>' | base64)
+
+helm install --namespace <NAMESPACE> --set vstsToken=${VSTS_TOKEN} --set vstsAccount=<VSTS ACCOUNT> --set vstsPool=<VSTS POOL> -f values.yaml vsts-agent .
+```
+
+Your deployment should look like this if everything works fine:
+
+```bash
+kubectl get pods --namespace <NAMESPACE> 
+NAME           READY     STATUS    RESTARTS   AGE
+vsts-agent-0   1/1       Running   0          1m
+vsts-agent-1   1/1       Running   0          1m
+vsts-agent-2   1/1       Running   0          1m
+```
+## Upgrading a deployed Chart
+
+A deployed chart can be upgraded as follows:
+
+```bash
+export VSTS_TOKEN=$(echo -n '<VSTS TOKEN>' | base64)
+
+helm upgrade --timeout 900 --namespace <NAMESPACE> --set vstsToken=${VSTS_TOKEN} --set vstsAccount=<VSTS ACCOUNT> --set vstsPool=<VSTS POOL> -f values.yaml vsts-agent . --wait
+```
+
+This command will upgrade the exiting chart and wait until the deployment is completed.
+
+## Uninstalling the Chart
+
+The chart can be uninstalled/deleted as follows:
+
+```console
+helm delete --purge vsts-agent
+```
+
+This command removes all the Kubernetes resources associated with the chart and deletes the helm release.
+
+## Validate the Chart
+
+You can validate the chart during development by using the `helm template` command.
+
+```bash
+helm template .
+```
+
+## Scale up the number of VSTS agents
+
+The number of VSTS agents can be easily increased to `10` by using the following command:
+
+```bash
+kubectl scale --namespace <NAMESPACE> statefulset/vsts-agent --replicas 10
+```
+## Contributing
 
 This project welcomes contributions and suggestions.  Most contributions require you to agree to a
 Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us