Support json primitives for enums

CHANGELOG.md

@@ -27,6 +27,11 @@ changes accumulate. Track in-flight protocol changes via PRs touching
 
 - `SessionSummary._meta` optional provider metadata field for lightweight
   session-list presentation hints.
+- `JsonPrimitive` type alias (`string | number | boolean | null`) in `types/common/state.ts`.
+
+### Changed
+
+- `ConfigPropertySchema.enum` now accepts `JsonPrimitive[]` instead of `string[]`, allowing numeric, boolean, and null enum values.
 
 ## [0.5.0] — Unreleased
 

clients/go/CHANGELOG.md

@@ -19,6 +19,11 @@ tag whose matching `## [X.Y.Z]` heading is missing from this file.
 - `SessionSummary.Meta` (wire `_meta`) optional provider metadata field for
   lightweight session-list presentation hints.
 
+### Changed
+
+- `ConfigPropertySchema.Enum` field is now `[]json.RawMessage` instead of `[]string`,
+  allowing numeric, boolean, and null enum values.
+
 ## [0.4.0] — 2026-06-19
 
 Implements AHP 0.4.0.

clients/go/ahptypes/state.generated.go

@@ -595,8 +595,8 @@ type ConfigPropertySchema struct {
 	Description *string `json:"description,omitempty"`
 	// JSON Schema: default value
 	Default *json.RawMessage `json:"default,omitempty"`
-	// JSON Schema: allowed values (typically used with `string` type)
-	Enum []string `json:"enum,omitempty"`
+	// JSON Schema: allowed values. May be primitives of any JSON type.
+	Enum []json.RawMessage `json:"enum,omitempty"`
 	// Display extension: human-readable label per enum value (parallel array)
 	EnumLabels []string `json:"enumLabels,omitempty"`
 	// Display extension: description per enum value (parallel array)
@@ -916,8 +916,8 @@ type SessionConfigPropertySchema struct {
 	Description *string `json:"description,omitempty"`
 	// JSON Schema: default value
 	Default *json.RawMessage `json:"default,omitempty"`
-	// JSON Schema: allowed values (typically used with `string` type)
-	Enum []string `json:"enum,omitempty"`
+	// JSON Schema: allowed values. May be primitives of any JSON type.
+	Enum []json.RawMessage `json:"enum,omitempty"`
 	// Display extension: human-readable label per enum value (parallel array)
 	EnumLabels []string `json:"enumLabels,omitempty"`
 	// Display extension: description per enum value (parallel array)

clients/kotlin/CHANGELOG.md

@@ -20,6 +20,11 @@ versions (`*-SNAPSHOT`) are explicitly rejected by the publish pipeline; bump
 - `SessionSummary.meta` (`_meta` on the wire) optional provider metadata field
   for lightweight session-list presentation hints.
 
+### Changed
+
+- `ConfigPropertySchema.enum` field is now `List<JsonElement>?` instead of
+  `List<String>?`, allowing numeric, boolean, and null enum values.
+
 ## [0.4.0] — 2026-06-19
 
 Implements AHP 0.4.0.

clients/kotlin/src/main/kotlin/com/microsoft/agenthostprotocol/generated/Commands.generated.kt

@@ -877,9 +877,9 @@ data class SessionConfigPropertySchema(
      */
     val default: JsonElement? = null,
     /**
-     * JSON Schema: allowed values (typically used with `string` type)
+     * JSON Schema: allowed values. May be primitives of any JSON type.
      */
-    val enum: List<String>? = null,
+    val enum: List<JsonElement>? = null,
     /**
      * Display extension: human-readable label per enum value (parallel array)
      */

clients/kotlin/src/main/kotlin/com/microsoft/agenthostprotocol/generated/State.generated.kt

@@ -957,9 +957,9 @@ data class ConfigPropertySchema(
      */
     val default: JsonElement? = null,
     /**
-     * JSON Schema: allowed values (typically used with `string` type)
+     * JSON Schema: allowed values. May be primitives of any JSON type.
      */
-    val enum: List<String>? = null,
+    val enum: List<JsonElement>? = null,
     /**
      * Display extension: human-readable label per enum value (parallel array)
      */

clients/rust/CHANGELOG.md

@@ -30,6 +30,8 @@ matching `## [X.Y.Z]` heading is missing from this file.
   instead of `native-tls`, dropping the OpenSSL link on Linux while still
   validating against the OS trust store. To keep the previous behaviour, depend
   on `ahp-ws` with `default-features = false, features = ["native-tls"]`.
+- `ConfigPropertySchema.enum` field is now `Option<Vec<AnyValue>>` instead of
+  `Option<Vec<String>>`, allowing numeric, boolean, and null enum values.
 
 ## [0.4.0] — 2026-06-19
 

clients/rust/crates/ahp-types/src/state.rs

@@ -819,9 +819,9 @@ pub struct ConfigPropertySchema {
     /// JSON Schema: default value
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub default: Option<AnyValue>,
-    /// JSON Schema: allowed values (typically used with `string` type)
+    /// JSON Schema: allowed values. May be primitives of any JSON type.
     #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub r#enum: Option<Vec<String>>,
+    pub r#enum: Option<Vec<AnyValue>>,
     /// Display extension: human-readable label per enum value (parallel array)
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub enum_labels: Option<Vec<String>>,
@@ -1209,9 +1209,9 @@ pub struct SessionConfigPropertySchema {
     /// JSON Schema: default value
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub default: Option<AnyValue>,
-    /// JSON Schema: allowed values (typically used with `string` type)
+    /// JSON Schema: allowed values. May be primitives of any JSON type.
     #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub r#enum: Option<Vec<String>>,
+    pub r#enum: Option<Vec<AnyValue>>,
     /// Display extension: human-readable label per enum value (parallel array)
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub enum_labels: Option<Vec<String>>,

clients/swift/AgentHostProtocol/Sources/AgentHostProtocol/Generated/Commands.generated.swift

@@ -977,8 +977,8 @@ public struct SessionConfigPropertySchema: Codable, Sendable {
     public var description: String?
     /// JSON Schema: default value
     public var `default`: AnyCodable?
-    /// JSON Schema: allowed values (typically used with `string` type)
-    public var `enum`: [String]?
+    /// JSON Schema: allowed values. May be primitives of any JSON type.
+    public var `enum`: [AnyCodable]?
     /// Display extension: human-readable label per enum value (parallel array)
     public var enumLabels: [String]?
     /// Display extension: description per enum value (parallel array)
@@ -1023,7 +1023,7 @@ public struct SessionConfigPropertySchema: Codable, Sendable {
         title: String,
         description: String? = nil,
         `default`: AnyCodable? = nil,
-        `enum`: [String]? = nil,
+        `enum`: [AnyCodable]? = nil,
         enumLabels: [String]? = nil,
         enumDescriptions: [String]? = nil,
         readOnly: Bool? = nil,

clients/swift/AgentHostProtocol/Sources/AgentHostProtocol/Generated/State.generated.swift

@@ -677,8 +677,8 @@ public final class ConfigPropertySchema: Codable, @unchecked Sendable {
     public var description: String?
     /// JSON Schema: default value
     public var `default`: AnyCodable?
-    /// JSON Schema: allowed values (typically used with `string` type)
-    public var `enum`: [String]?
+    /// JSON Schema: allowed values. May be primitives of any JSON type.
+    public var `enum`: [AnyCodable]?
     /// Display extension: human-readable label per enum value (parallel array)
     public var enumLabels: [String]?
     /// Display extension: description per enum value (parallel array)
@@ -714,7 +714,7 @@ public final class ConfigPropertySchema: Codable, @unchecked Sendable {
         title: String,
         description: String? = nil,
         `default`: AnyCodable? = nil,
-        `enum`: [String]? = nil,
+        `enum`: [AnyCodable]? = nil,
         enumLabels: [String]? = nil,
         enumDescriptions: [String]? = nil,
         readOnly: Bool? = nil,

clients/swift/CHANGELOG.md

@@ -22,6 +22,11 @@ the tag matches the version pinned in [`VERSION`](VERSION).
 - `SessionSummary.meta` (`_meta` on the wire) optional provider metadata field
   for lightweight session-list presentation hints.
 
+### Changed
+
+- `ConfigPropertySchema.enum` field is now `[AnyCodable]?` instead of
+  `[String]?`, allowing numeric, boolean, and null enum values.
+
 ## [0.4.0] — 2026-06-19
 
 Implements AHP 0.4.0.

clients/typescript/CHANGELOG.md

@@ -24,6 +24,12 @@ hotfix escape hatch.
 
 - `SessionSummary._meta` optional provider metadata field for lightweight
   session-list presentation hints.
+- Exported `JsonPrimitive` type alias (`string | number | boolean | null`).
+
+### Changed
+
+- `ConfigPropertySchema.enum` field is now `JsonPrimitive[]` instead of
+  `string[]`, allowing numeric, boolean, and null enum values.
 
 ### Fixed
 

schema/actions.schema.json

@@ -2044,9 +2044,9 @@
         "enum": {
           "type": "array",
           "items": {
-            "type": "string"
+            "$ref": "#/$defs/JsonPrimitive"
           },
-          "description": "JSON Schema: allowed values (typically used with `string` type)"
+          "description": "JSON Schema: allowed values. May be primitives of any JSON type."
         },
         "enumLabels": {
           "type": "array",
@@ -2753,9 +2753,9 @@
         "enum": {
           "type": "array",
           "items": {
-            "type": "string"
+            "$ref": "#/$defs/JsonPrimitive"
           },
-          "description": "JSON Schema: allowed values (typically used with `string` type)"
+          "description": "JSON Schema: allowed values. May be primitives of any JSON type."
         },
         "enumLabels": {
           "type": "array",
@@ -5992,6 +5992,21 @@
       ],
       "description": "A string that may optionally be rendered as Markdown.\n\n- A plain `string` is rendered as-is (no Markdown processing).\n- An object with `{ markdown: string }` is rendered with Markdown formatting."
     },
+    "JsonPrimitive": {
+      "oneOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "number"
+        },
+        {
+          "type": "boolean"
+        },
+        {}
+      ],
+      "description": "A primitive JSON value: a string, number, boolean, or `null`."
+    },
     "ChildCustomizationType": {
       "oneOf": [
         {},

schema/commands.schema.json

@@ -1382,9 +1382,9 @@
         "enum": {
           "type": "array",
           "items": {
-            "type": "string"
+            "$ref": "#/$defs/JsonPrimitive"
           },
-          "description": "JSON Schema: allowed values (typically used with `string` type)"
+          "description": "JSON Schema: allowed values. May be primitives of any JSON type."
         },
         "enumLabels": {
           "type": "array",
@@ -2091,9 +2091,9 @@
         "enum": {
           "type": "array",
           "items": {
-            "type": "string"
+            "$ref": "#/$defs/JsonPrimitive"
           },
-          "description": "JSON Schema: allowed values (typically used with `string` type)"
+          "description": "JSON Schema: allowed values. May be primitives of any JSON type."
         },
         "enumLabels": {
           "type": "array",

schema/errors.schema.json

@@ -234,9 +234,9 @@
         "enum": {
           "type": "array",
           "items": {
-            "type": "string"
+            "$ref": "#/$defs/JsonPrimitive"
           },
-          "description": "JSON Schema: allowed values (typically used with `string` type)"
+          "description": "JSON Schema: allowed values. May be primitives of any JSON type."
         },
         "enumLabels": {
           "type": "array",
@@ -943,9 +943,9 @@
         "enum": {
           "type": "array",
           "items": {
-            "type": "string"
+            "$ref": "#/$defs/JsonPrimitive"
           },
-          "description": "JSON Schema: allowed values (typically used with `string` type)"
+          "description": "JSON Schema: allowed values. May be primitives of any JSON type."
         },
         "enumLabels": {
           "type": "array",

schema/notifications.schema.json

@@ -368,9 +368,9 @@
         "enum": {
           "type": "array",
           "items": {
-            "type": "string"
+            "$ref": "#/$defs/JsonPrimitive"
           },
-          "description": "JSON Schema: allowed values (typically used with `string` type)"
+          "description": "JSON Schema: allowed values. May be primitives of any JSON type."
         },
         "enumLabels": {
           "type": "array",
@@ -1077,9 +1077,9 @@
         "enum": {
           "type": "array",
           "items": {
-            "type": "string"
+            "$ref": "#/$defs/JsonPrimitive"
           },
-          "description": "JSON Schema: allowed values (typically used with `string` type)"
+          "description": "JSON Schema: allowed values. May be primitives of any JSON type."
         },
         "enumLabels": {
           "type": "array",

schema/state.schema.json

@@ -145,9 +145,9 @@
         "enum": {
           "type": "array",
           "items": {
-            "type": "string"
+            "$ref": "#/$defs/JsonPrimitive"
           },
-          "description": "JSON Schema: allowed values (typically used with `string` type)"
+          "description": "JSON Schema: allowed values. May be primitives of any JSON type."
         },
         "enumLabels": {
           "type": "array",
@@ -854,9 +854,9 @@
         "enum": {
           "type": "array",
           "items": {
-            "type": "string"
+            "$ref": "#/$defs/JsonPrimitive"
           },
-          "description": "JSON Schema: allowed values (typically used with `string` type)"
+          "description": "JSON Schema: allowed values. May be primitives of any JSON type."
         },
         "enumLabels": {
           "type": "array",
@@ -4093,6 +4093,21 @@
       ],
       "description": "A string that may optionally be rendered as Markdown.\n\n- A plain `string` is rendered as-is (no Markdown processing).\n- An object with `{ markdown: string }` is rendered with Markdown formatting."
     },
+    "JsonPrimitive": {
+      "oneOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "number"
+        },
+        {
+          "type": "boolean"
+        },
+        {}
+      ],
+      "description": "A primitive JSON value: a string, number, boolean, or `null`."
+    },
     "ChildCustomizationType": {
       "oneOf": [
         {},

scripts/generate-go.ts

@@ -149,6 +149,10 @@ function mapType(tsType: string): string {
   if (tsType === 'object') return 'json.RawMessage';
   if (tsType === 'true' || tsType === 'false') return 'bool';
 
+  // A primitive JSON value (`string | number | boolean | null`) has no single
+  // Go counterpart — represent it as an arbitrary JSON value.
+  if (tsType === 'JsonPrimitive') return 'json.RawMessage';
+
   if (tsType === 'URI') return 'URI';
   if (tsType === 'StringOrMarkdown') return 'StringOrMarkdown';
 
@@ -1849,6 +1853,7 @@ function checkExhaustiveness(project: Project): void {
 
   const knownSpecial = new Set<string>([
     'URI',
+    'JsonPrimitive',
     'BaseParams',
     'StringOrMarkdown',
     'ToolCallState',

scripts/generate-kotlin.ts

@@ -128,6 +128,9 @@ function mapType(tsType: string): string {
   if (tsType === 'boolean') return 'Boolean';
   if (tsType === 'unknown') return 'JsonElement';
   if (tsType === 'object') return 'JsonElement';
+  // A primitive JSON value (`string | number | boolean | null`) maps to a
+  // generic JSON element.
+  if (tsType === 'JsonPrimitive') return 'JsonElement';
   if (tsType === 'true' || tsType === 'false') return 'Boolean';
 
   // Type aliases
@@ -1832,6 +1835,7 @@ function checkExhaustiveness(project: Project): void {
 
   const knownSpecial = new Set<string>([
     'URI',                          // type alias for string
+    'JsonPrimitive',                // primitive JSON value alias; mapped to JsonElement
     'BaseParams',                    // marker base interface; flattened into each command params struct
     // PingParams shape is `interface PingParams extends BaseParams { channel: 'ahp-root://' }`
     // (i.e. a `BaseParams` with `channel` narrowed to a string literal). We don't

scripts/generate-rust.ts

@@ -139,6 +139,10 @@ function mapType(tsType: string, propName?: string, containerName?: string): str
   if (tsType === 'object') return 'AnyValue';
   if (tsType === 'true' || tsType === 'false') return 'bool';
 
+  // A primitive JSON value (`string | number | boolean | null`) has no single
+  // Rust counterpart — represent it as an arbitrary JSON value.
+  if (tsType === 'JsonPrimitive') return 'AnyValue';
+
   if (tsType === 'URI') return 'Uri';
   if (tsType === 'StringOrMarkdown') return 'StringOrMarkdown';
 
@@ -1717,6 +1721,7 @@ function checkExhaustiveness(project: Project): void {
 
   const knownSpecial = new Set<string>([
     'URI',
+    'JsonPrimitive',
     'BaseParams',
     'StringOrMarkdown',
     'ToolCallState',