Add README, LICENSE (GPL-3), and update config dir to XDG path

Config moved to ~/.config/portainer-cli/config.yml following XDG convention.
README covers installation, configuration, all commands, container name
resolution logic, and debugging. Tool noted as AI-generated.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

LICENSE

@@ -0,0 +1,26 @@
+GNU GENERAL PUBLIC LICENSE
+Version 3, 29 June 2007
+
+Copyright (C) 2026 Grzegorz Luszczek
+
+Everyone is permitted to copy and distribute verbatim copies of this license
+document, but changing it is not allowed.
+
+                            PREAMBLE
+
+The GNU General Public License is a free, copyleft license for software and
+other kinds of works.
+
+When we speak of free software, we are referring to freedom, not price. Our
+General Public Licenses are designed to make sure that you have the freedom
+to distribute copies of free software (and charge for them if you wish), that
+you receive source code or can get it if you want it, that you can change the
+software or use pieces of it in new free programs, and that you know you can
+do these things.
+
+To protect your rights, we need to prevent others from denying you these
+rights or asking you to surrender the rights. Therefore, you have certain
+responsibilities if you distribute copies of the software, or if you modify
+it: responsibilities to respect the freedom of others.
+
+For the full license text, see: https://www.gnu.org/licenses/gpl-3.0.txt

README.md

@@ -0,0 +1,150 @@
+# portainer-cli
+
+A Ruby command-line tool for interacting with [Portainer](https://www.portainer.io/) via its REST API. List environments, stacks, containers, volumes and networks — and open fully interactive shells inside running containers directly from your terminal.
+
+> **This tool was fully generated by AI** (Claude, by Anthropic) through an iterative conversation-driven development session.
+
+## Features
+
+- List endpoints, stacks, containers, volumes, and networks
+- Create stacks (from file or inline compose) and containers
+- **Interactive exec into containers** via WebSocket — works like `docker exec -it` but through Portainer
+- Smart container name resolution: fuzzy matching using Docker Compose naming conventions (`<stack>-<service>-<N>`)
+- Automatic endpoint resolution — no need to look up endpoint IDs manually
+- Supports both API key and JWT token authentication
+- Configurable SSL verification (useful for self-signed certificates)
+- `--run CMD` flag for running a specific command (e.g. `rails c`)
+- `--quiet` flag for scripting and AI agent use cases
+
+## Requirements
+
+- Ruby 3.x
+- [`websocket`](https://rubygems.org/gems/websocket) gem
+- A running Portainer instance (v2.x or later)
+
+## Installation
+
+```sh
+git clone https://github.com/grzlus/portainer-cli
+cd portainer-cli
+bundle install
+chmod +x bin/portainer-cli
+
+# Link into your PATH (adjust the target to wherever suits you)
+ln -sf "$PWD/bin/portainer-cli" ~/bin/portainer-cli
+```
+
+## Configuration
+
+```sh
+portainer-cli configure
+```
+
+You will be prompted for:
+
+- **Portainer URL** — e.g. `https://portainer.example.com`
+- **Authentication** — API key (recommended, no expiry) or JWT token
+- **SSL verification** — answer `n` if your instance uses a self-signed certificate
+
+Configuration is saved to `~/.config/portainer-cli/config.yml` (mode `0600`).
+
+### Manual config
+
+```yaml
+# ~/.config/portainer-cli/config.yml
+url: https://portainer.example.com
+api_key: ptr_xxxxxxxxxxxxxxxxxxxxxxxxxxxx
+ssl_verify: true
+```
+
+## Usage
+
+### List resources
+
+```sh
+portainer-cli list endpoints
+portainer-cli list stacks
+portainer-cli list containers <endpoint-id>
+portainer-cli list volumes    <endpoint-id>
+portainer-cli list networks   <endpoint-id>
+```
+
+### Open an interactive shell
+
+```sh
+# Resolves endpoint automatically from the stack name.
+# Container name defaults to the stack name, then falls back to 'app'.
+portainer-cli console <stack>
+portainer-cli console <stack> <container>
+
+# Examples
+portainer-cli console myapp
+portainer-cli console myapp worker
+portainer-cli console myapp --shell /bin/bash
+```
+
+### Run a specific command
+
+```sh
+portainer-cli console myapp --run "rails c"
+portainer-cli console myapp --run "bundle exec rake db:migrate"
+```
+
+### Quiet mode (scripting / AI agents)
+
+Suppresses all status output — only the container's own stdout/stderr is printed.
+
+```sh
+portainer-cli console myapp --quiet --run "rails runner 'puts User.count'"
+```
+
+### Create resources
+
+```sh
+# Stack from a compose file
+portainer-cli create stack --endpoint 1 --name myapp --file docker-compose.yml
+
+# Stack from inline compose
+portainer-cli create stack --endpoint 1 --name myapp --compose "version: '3'
+services:
+  web:
+    image: nginx"
+
+# Container
+portainer-cli create container --endpoint 1 --image nginx:alpine --name web \
+  --port 8080:80 --env APP_ENV=production
+```
+
+### Low-level exec (manual endpoint ID)
+
+```sh
+portainer-cli exec <endpoint-id> <container-name-or-id>
+portainer-cli exec <endpoint-id> <container-name-or-id> --shell /bin/bash
+```
+
+## Container name resolution
+
+When using `console`, names are resolved in this order:
+
+1. **Exact match** — full container name or ID prefix
+2. **Compose pattern** — `<stack>-<service>-<N>` (e.g. `librarian` → `librarian-librarian-1`)
+3. **Substring match** — scoped to the stack's own containers
+4. **`app` fallback** — tries `<stack>-app-1` as a last resort
+
+If multiple containers match ambiguously, a list is printed and the command exits.
+
+## Debugging
+
+```sh
+portainer-cli --debug console myapp
+```
+
+Prints the WebSocket URL, auth headers, and the full HTTP upgrade handshake request/response — useful for diagnosing connection issues behind reverse proxies.
+
+## License
+
+This program is free software: you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free Software
+Foundation, either version 3 of the License, or (at your option) any later version.
+
+See [LICENSE](LICENSE) for the full text.

lib/portainer_cli/config.rb

@@ -5,7 +5,7 @@ require 'fileutils'
 
 module PortainerCli
   class Config
-    CONFIG_DIR  = File.expand_path('~/.portainer-cli').freeze
+    CONFIG_DIR  = File.expand_path('~/.config/portainer-cli').freeze
     CONFIG_FILE = File.join(CONFIG_DIR, 'config.yml').freeze
 
     attr_accessor :url, :token, :api_key, :ssl_verify