Diff and check command line formatting

.gitignore

@@ -1 +1,2 @@
 /.idea
+/.vscode

README.md

@@ -54,19 +54,44 @@ Gherkin Utils is [available on Maven Central](https://central.sonatype.com/artif
 
 ## Command line
 
-The command-line tool can be used to format `.feature` files or to translate `.feature` files
-into `.feature.md` files.
+Running Gherkin Utils from the command line provides formatting and conversion features.
 
-The following example translates all `.feature` files to `.feature.md` files and then deletes the `.feature` files (see [Markdown with Gherkin](https://github.com/cucumber/common/blob/main/gherkin/MARKDOWN_WITH_GHERKIN.md)).
-**Note**: Globs must be quoted to prevent the shell from expanding the globs.
+```bash
+> npx @cucumber/gherkin-utils format features
+❌ 7 files failed to format
+🥒 14 files left unchanged
+🥒 25 files reformatted
+```
 
-```console
-npx @cucumber/gherkin-utils format --move "features/**/*.feature" "features/**/*.feature.md"
+To run Gherkin Utils as a formatter, try any of the following:
+
+```bash
+# Format `file.feature`
+npx @cucumber/gherkin-utils format features/file.feature
+# Format `one.feature` and `two.feature`
+npx @cucumber/gherkin-utils format features/one.feature features/two.feature
+# Format all feature files in `features/` (and any subdirectories)
+npx @cucumber/gherkin-utils format features/
+# Format all feature files ending with `_test.feature` in `features`
+npx @cucumber/gherkin-utils format features/**/*_test.feature
+# Check files that would be reformatted in `features/`
+npx @cucumber/gherkin-utils format --check features/
+# Check files that would be reformatted in `features/` and output the diff
+npx @cucumber/gherkin-utils format --diff features/
+```
+
+To convert to [Markdown with Gherkin](https://github.com/cucumber/common/blob/main/gherkin/MARKDOWN_WITH_GHERKIN.md) or feature files while formatting, try the following:
+
+```bash
+# Format all feature files in `features/` (and any subdirectories) and convert to gherkin markdown
+npx @cucumber/gherkin-utils format --to-syntax=markdown features/
+# Format all feature files in `features/` (and any subdirectories) and convert to gherkin
+npx @cucumber/gherkin-utils format --to-syntax=gherkin features/
 ```
 
 For more details on usage, see the help menu.
 
-```console
+```bash
 npx @cucumber/gherkin-utils --help
 ```
 
@@ -147,3 +172,7 @@ const scenarioNameFinder = new GherkinDocumentWalker({}, {
   handleScenario: (scenario) => allScenarioNames.push(scenario.name),
 })
 ```
+
+## Feedback
+
+If you discover a bug, or have a suggestion for a feature request, please submit an [issue](https://github.com/cucumber/gherkin-utils/issues).