feat(docs): Add basic documentation to docs

Signed-off-by: Denys Fedoryshchenko <[email protected]>

docs/index.md

@@ -1,3 +1,73 @@
 # kci-dev
 
 kci-dev is a cmdline tool for interact with a enabled KernelCI server
+Purpose of this tool to provide a easy way to use features of KernelCI Pipeline instance.
+
+## Installation
+
+Using poetry and virtualenv
+```sh
+virtualenv .venv
+source .venv/bin/activate
+pip install poetry
+poetry install
+poetry run kci-dev
+```
+
+## Configuration
+
+kci-dev uses a configuration file .kci-dev.toml in the program directory.
+```toml
+default_instance="staging"
+[local]
+host="https://127.0.0.1"
+token="example"
+
+[staging]
+host="https://staging.kernelci.org:9100/"
+token="SOMEVERYSECRETTOKEN"
+
+[production]
+host="https://kernelci-pipeline.westus3.cloudapp.azure.com/"
+token="example"
+```
+
+Where `default_instance` is the default instance to use, if not provided in the command line.
+In section `local`, `staging`, `production` you can provide the host and token for the available instances.
+host is the URL of the KernelCI Pipeline API endpoint, and token is the API token to use for authentication.
+If you are using KernelCI Pipeline instance, you can get the token from the project maintainers.
+If it is a local instance, you can generate your token using kernelci-pipeline/tools/jwt_generator.py script.
+
+## Options
+
+### instance
+You can provide the instance name to use for the command.
+
+Example:
+```sh
+kci-dev --instance staging
+```
+
+### settings
+
+You can provide the configuration file path to use for the command.
+
+Example:
+```sh
+kci-dev --settings /path/to/.kci-dev.toml
+```
+
+## Commands
+
+### testretry
+
+This command will retry the failed tests. In some cases tests may fail due to network issues, hardware problems,
+nature of test (flaky), etc. This command will retry the failed tests, and create additional test jobs for the failed tests.
+After observing the results, you can decide if test results were reliable, not, or maybe even test need improvement.
+
+Example:
+```sh
+kci-dev testretry --nodeid <testnodeid>
+```
+
+testnodeid is the node id of the test job, which you can get from the KernelCI dashboard. Usually it is hexadecimal string.