document bicep console

Author: mumian

articles/azure-resource-manager/bicep/bicep-cli.md

@@ -2,7 +2,7 @@
 title: Bicep CLI commands 
 description: Learn about the commands that you can use in the Bicep CLI. These commands include building JSON Azure Resource Manager templates from Bicep.
 ms.topic: reference
-ms.date: 03/02/2026
+ms.date: 04/09/2026
 ms.custom: devx-track-azurecli, devx-track-bicep, devx-track-arm-template
 ---
 
@@ -138,6 +138,201 @@ az bicep build-params --file params.bicepparam
 
 This command converts a _params.bicepparam_ parameters file into a _params.json_ JSON parameters file.
 
+## console
+
+The `console` command is available in Bicep CLI v0.42.1 or later. It provides an interactive Read-Eval-Print Loop (REPL) environment for Bicep expressions. It allows you to experiment with Bicep functions and expressions in an interactive console session. It supports the following features:
+
+* **Interactive Expression Evaluation**: Enter Bicep expressions and see their evaluated results immediately
+* **Variable Declarations**: Define variables using var name = expression syntax and reuse them in subsequent expressions
+* **Multi-line Input**: Support for complex multi-line expressions with automatic structural completion detection
+* **Syntax Highlighting**: Real-time syntax highlighting for input and output
+
+The `console` command has these limitations:
+
+* No support for expressions requiring Azure context, e.g. resourceGroup()
+* No support for for-loop expressions, e.g. [for i in range(0, x): i]
+* No persistent state between console sessions
+* No completions support
+
+Use the following command to start a Bicep console session:
+
+# [Bicep CLI](#tab/bicep-cli)
+
+```powershell
+bicep console
+```
+
+# [Azure CLI](#tab/azure-cli)
+
+N/A
+
+---
+
+To exit the console, press `ESC` or use the `exit` command.
+
+### Examples
+
+#### Simple Expressions
+```bicep
+> 1 + 2
+3
+
+> 'Hello, ' + 'World!'
+'Hello, World!'
+
+> length(['a', 'b', 'c'])
+3
+
+```
+
+#### Simple Expressions
+
+```bicep
+> 1 + 2
+3
+
+> 'Hello, ${'World!'}'
+'Hello, World!'
+
+> length(['a', 'b', 'c'])
+3
+```
+
+#### Variable Declarations
+
+```bicep
+> var myName = 'John'
+> var greeting = 'Hello, ${myName}!'
+> greeting
+'Hello, John!'
+```
+
+#### Multi-line Expressions
+
+The console automatically detects when expressions are structurally complete:
+
+```bicep
+> var config = {
+  name: 'myApp'
+  version: '1.0.0'
+  settings: {
+    debug: true
+    timeout: 30
+  }
+}
+> config.settings.debug
+true
+```
+
+#### Complex Expressions
+
+##### Lambdas
+
+```bicep
+> var users = [
+  { name: 'Alice', age: 30 }
+  { name: 'Bob', age: 25 }
+]
+> map(users, user => user.name)
+['Alice', 'Bob']
+
+> filter(users, user => user.age > 26)
+[
+  {
+    age: 30
+    name: 'Alice'
+  }
+]
+```
+
+##### User-defined types and functions
+
+```bicep
+> type PersonType = {
+  name: string
+  age: int
+}
+> func sayHi(person PersonType) string => 'Hello ${person.name}, you are ${person.age} years old!'
+> var alice = {
+  name: 'Alice'
+  age: 30
+}
+> [ sayHi(alice), sayHi({ name: 'Bob', age: 25 })]
+[
+  'Hello Alice, you are 30 years old!'
+  'Hello Bob, you are 25 years old!'
+]
+```
+
+#### Loading content from files
+
+Bicep console also supports the [`load*()` functions](./bicep-functions-files.md#file-functions-for-bicep). Note: The directory from which the `bicep console` command is run is used as the _current directory_ when evaluating the `load*()` functions
+
+The following example shows how to use `loadDirectoryFileInfo()` to load information about all Bicep files in a directory:
+
+```bicep
+> loadDirectoryFileInfo('./modules/', '*.bicep')
+[
+  {
+    relativePath: 'C:/Bicep/modules/appService.bicep'
+    baseName: 'appService.bicep'
+    extension: '.bicep'
+  }
+]
+```
+
+#### Piping and standard input/output redirection
+
+The console command supports evaluating expressions provided through piping or redirected standard input, i.e.:
+
+**Powershell**:
+
+```powershell
+# piped input
+"parseCidr('10.144.0.0/20')" | bicep console
+```
+
+**Bash**:
+
+```bash
+# piped input
+echo "parseCidr('10.144.0.0/20')" | bicep console
+# stdin redirection from file content
+bicep console < test.txt
+```
+
+Multi-line input is also supported, i.e:
+
+```powershell
+"{
+> foo: 'bar'
+> }.foo" | bicep console
+```
+
+The output is `'bar'`.
+
+Output redirection is also supported:
+
+```bash
+"toObject([{name:'Evie', age:4},{name:'Casper', age:3}], x => x.name)" | bicep console > output.json
+more output.json
+```
+
+The output is :
+
+```json
+{
+  Evie: {
+    name: 'Evie'
+    age: 4
+  }
+  Casper: {
+    name: 'Casper'
+    age: 3
+  }
+}
+```
+
 ## decompile
 
 The `decompile` command converts a JSON ARM template to a Bicep file: