Update README to include CLI usage and options for image generation

README.md

@@ -1,4 +1,4 @@
-# Adobe Firefly Python Client
+# Adobe Firefly Python Client Library & CLI
 
 [![CI](https://github.com/msabramo/python-firefly/actions/workflows/ci.yml/badge.svg?branch=main)](https://github.com/msabramo/python-firefly/actions/workflows/ci.yml)
 
@@ -43,6 +43,54 @@ print("Content class:", response.contentClass)
   - Generate an image from a text prompt. Returns a response object with attributes matching the API response (including outputs, size, contentClass, etc).
   - Additional keyword arguments are passed as parameters to the API.
 
+## Command Line Interface (CLI)
+
+The `firefly` CLI allows you to generate images from the command line using the Adobe Firefly API.
+
+### Usage
+
+```sh
+export FIREFLY_CLIENT_ID="abc123"
+export FIREFLY_CLIENT_SECRET="xyz456"
+```
+
+```sh
+firefly image generate \
+  --prompt="a realistic illustration of a cat coding" \
+  --show-images
+```
+
+### Options
+
+- `--client-id TEXT`                        Your Adobe Firefly client ID [env var: FIREFLY_CLIENT_ID] [default: None]
+- `--client-secret TEXT`                    Your Adobe Firefly client secret [env var: FIREFLY_CLIENT_SECRET] [default: None]
+- `--prompt TEXT` *                         Text prompt for image generation [required]
+- `--num-variations INTEGER`                Number of images to generate (numVariations) [default: None]
+- `--style TEXT`                            Style object as JSON string (presets, imageReference, strength, etc.) [default: None]
+- `--structure TEXT`                        Structure object as JSON string (strength, imageReference, etc.) [default: None]
+- `--prompt-biasing-locale-code TEXT`       Locale code for prompt biasing (promptBiasingLocaleCode), e.g., en-US, en-IN, zh-CN [default: None]
+- `--negative-prompt TEXT`                  Negative prompt to avoid certain content [default: None]
+- `--seed INTEGER`                          Seed for deterministic output [default: None]
+- `--aspect-ratio TEXT`                     Aspect ratio, e.g. '1:1', '16:9' [default: None]
+- `--output-format TEXT`                    Output format, e.g. 'jpeg', 'png' [default: None]
+- `--content-class TEXT`                    Content class: 'photo' or 'art' [default: None]
+- `--download/--no-download`                Download the generated image to a file (filename is taken from the image URL) [default: no-download]
+- `--show-images/--no-show-images`          Display the image in the terminal after download. [default: no-show-images]
+- `--use-mocks/--no-use-mocks`              Mock API responses for testing without a valid client secret. [default: no-use-mocks]
+- `--format TEXT`                           Output format: 'text' (default) or 'json' for pretty-printed JSON response. [default: text]
+- `--verbose/--no-verbose`                  Print status messages to stderr. [default: no-verbose]
+- `--help`                                  Show this message and exit
+
+### Example
+
+```sh
+firefly image generate \
+  --prompt="a futuristic city skyline at sunset" \
+  --show-images
+```
+
+The CLI will print the generated image URL.
+
 ## Error Handling
 
 - `FireflyAuthError`: Raised for authentication/token errors
@@ -52,4 +100,4 @@ print("Content class:", response.contentClass)
 
 - [Adobe Firefly API Documentation]
 
-[Adobe Firefly API Documentation]: https://developer.adobe.com/firefly-services/docs/firefly-api/guides/#generate-an-image
+[Adobe Firefly API Documentation]: https://developer.adobe.com/firefly-services/docs/firefly-api/guides/#generate-an-image