docs: Update resource schema reference (#1708)

Author: Gijsreyn

docs/reference/schemas/resource/manifest/adapter.md

@@ -1,6 +1,6 @@
 ---
 description: JSON schema reference for the 'adapter' property in a DSC Resource manifest
-ms.date:     07/03/2025
+ms.date:     09/01/2026
 ms.topic:    reference
 title:       DSC Resource manifest adapter property schema reference
 ---
@@ -23,7 +23,9 @@ Type:          object
 
 DSC Resource Adapters must define the `adapter` property in their manifest. This property
 identifies the resource as an adapter and defines how DSC can call the adapter to get the resources
-the adapter supports and how to pass resource instances to the adapter.
+the adapter supports and how to pass resource instances to the adapter. When a manifest defines
+this property and doesn't define the [kind][01] property, DSC infers the resource kind as
+`adapter`.
 
 ## Examples
 
@@ -39,64 +41,114 @@ This example is from the `Microsoft.DSC/PowerShell` DSC Resource Adapter.
       "-NoLogo",
       "-NonInteractive",
       "-NoProfile",
+      "-ExecutionPolicy",
+      "Bypass",
       "-Command",
-      "./powershell.resource.ps1 List"
+      "./psDscAdapter/powershell.resource.ps1 List"
     ]
-    },
-  "config": "full"
-},
+  },
+  "inputKind": "full"
+}
 ```
 
-The manifest sets `config` to `full`, indicating that the adapter expects a JSON blob representing
-the full and unprocessed configuration from `stdin`.
+The manifest sets `inputKind` to `full`, indicating that the adapter expects a JSON blob
+representing the full and unprocessed configuration from `stdin`.
 
 It defines `list.executable` as `pwsh`. The arguments defined in `list.args` ensure that DSC runs
 PowerShell:
 
 - Without the logo banner
 - In non-interactive mode
 - Without loading any profile scripts
-- To invoke the `powershell.resource.ps1` script in the same folder as the `dsc` command and
-  pass the `List` argument.
+- With the execution policy set to `Bypass`
+- To invoke the `powershell.resource.ps1` script in the `psDscAdapter` folder next to the manifest
+  and pass the `List` argument.
 
 With this definition, DSC calls the `list` method for this adapter by running:
 
 ```sh
-pwsh -NoLogo -NonInteractive -NoProfile -Command "./powershellgroup.resource.ps1 List"
+pwsh -NoLogo -NonInteractive -NoProfile -ExecutionPolicy Bypass \
+  -Command "./psDscAdapter/powershell.resource.ps1 List"
 ```
 
-## Required Properties
+### Example 2 - Microsoft.Adapter/PowerShell
+
+This example is from the `Microsoft.Adapter/PowerShell` DSC Resource Adapter.
+
+```json
+"adapter": {
+  "list": {
+    "executable": "pwsh",
+    "args": [
+      "-NoLogo",
+      "-NonInteractive",
+      "-NoProfile",
+      "-ExecutionPolicy",
+      "Bypass",
+      "-Command",
+      "./psDscAdapter/powershell.resource.ps1",
+      "List",
+      "-ResourceType",
+      "Single"
+    ]
+  },
+  "inputKind": "single"
+}
+```
+
+The manifest sets `inputKind` to `single`, indicating that DSC should invoke the adapter for one
+adapted resource instance at a time. The adapter's `get`, `set`, `test`, and `export` definitions
+use the [resource type argument][02] and [resource path argument][03] to identify which adapted
+resource to invoke.
+
+## Required properties
 
 The `adapter` definition must include these properties:
 
-- [config](#config)
-- [list](#list)
+- [inputKind](#inputkind)
 
 ## Properties
 
-### config
+### inputKind
 
-The `config` property defines how the adapter expects to receive resource configurations. The
+The `inputKind` property defines how the adapter expects to receive resource configurations. The
 value must be one of the following options:
 
 - `full` - Indicates that the adapter expects a JSON blob containing the full and unprocessed
-  configuration as a single JSON blob over `stdin`.
+  configuration as a single JSON blob over `stdin`. DSC adds a `metadata` property with the
+  `Microsoft.DSC.context` value set to `configuration` to the input so the adapter can distinguish
+  a full configuration from a single resource instance.
 - `sequence` - Indicates that the adapter expects each resource's configuration as a
-  [JSON Line][01] over `stdin`.
+  [JSON Line][04] over `stdin`.
+- `single` - Indicates that the adapter expects a single adapted resource instance. DSC invokes
+  the adapter's operation commands directly for each adapted resource instance and passes the
+  instance properties as the input for the command. Use the [resource type argument][02],
+  [resource path argument][03], [resource version argument][05], and
+  [adapted content argument][06] in the operation definitions to tell the adapter which adapted
+  resource to invoke.
+
+Prior to DSC version 3.2.0, this property was named `config`. DSC still accepts the `config` name
+for backward compatibility, but new manifests should use `inputKind`.
 
 ```yaml
 Type:        string
-ValidValues: [full, sequence]
+Required:    true
+ValidValues: [full, sequence, single]
 ```
 
 ### list
 
 The `list` property defines how to call the adapter to list the resources it supports. The value
-of this property must be an object and define the `executable` sub-property.
+of this property must be an object and define the `executable` sub-property. For more information
+about the expected output, see [DSC resource list operation stdout schema reference][07].
+
+When this property isn't defined, DSC can't discover the adapter's resources by invoking the
+adapter. Users can still define adapted resources for the adapter with adapted resource manifests
+that specify the adapter with their `requireAdapter` property.
 
 ```yaml
 Type:               object
-Required:           true
+Required:           false
 RequiredProperties: [executable]
 ```
 
@@ -115,12 +167,21 @@ Required: true
 #### args
 
 The `args` sub-property defines an array of strings to pass as arguments to the command. DSC passes
-the arguments to the command in the order they're specified.
+the arguments to the command in the order they're specified. Unlike the `args` property for the
+operation methods, this array only accepts strings.
 
 ```yaml
-Type:     array
-Required: false
-Default:  []
+Type:      array
+Required:  false
+Default:   []
+ItemsType: string
 ```
 
-[01]: https://jsonlines.org/
+<!-- Link reference definitions -->
+[01]: root.md#kind
+[02]: get.md#resource-type-argument
+[03]: get.md#resource-path-argument
+[04]: https://jsonlines.org/
+[05]: get.md#resource-version-argument
+[06]: get.md#adapted-content-argument
+[07]: ../stdout/list.md