refactor(#1375): type config.set, config.get, model.options and client.capabilities (#1393)

app/src/main/java/com/m57/hermescontrol/data/ws/HermesWsClient.kt

@@ -10,6 +10,7 @@ import com.m57.hermescontrol.data.remote.NetworkMonitor
 import com.m57.hermescontrol.data.remote.OkHttpProvider
 import com.m57.hermescontrol.data.remote.await
 import com.m57.hermescontrol.data.session.ActiveSessionHolder
+import com.m57.hermescontrol.data.ws.contract.ClientCapabilitiesParams
 import com.m57.hermescontrol.data.ws.contract.PromptSubmitParams
 import com.m57.hermescontrol.data.ws.contract.RpcMethod
 import com.m57.hermescontrol.data.ws.contract.RpcMethods
@@ -364,8 +365,11 @@ object HermesWsClient {
                     // Older gateways may reject this method; that is harmless.
                     runCatching {
                         send(
-                            WsMethods.CLIENT_CAPABILITIES,
-                            mapOf("server_requests" to true),
+                            RpcMethods.CLIENT_CAPABILITIES.name,
+                            encodeParams(
+                                RpcMethods.CLIENT_CAPABILITIES,
+                                ClientCapabilitiesParams(serverRequests = true),
+                            ),
                             onSent = { id -> capabilityRequestIds.add(id) },
                             queueIfDisconnected = false,
                         )

app/src/main/java/com/m57/hermescontrol/data/ws/ModelOptionsRepository.kt

@@ -5,6 +5,8 @@ import com.m57.hermescontrol.data.remote.ApiClient
 import com.m57.hermescontrol.data.remote.NetworkResult
 import com.m57.hermescontrol.data.remote.OkHttpProvider
 import com.m57.hermescontrol.data.remote.safeApiCall
+import com.m57.hermescontrol.data.ws.contract.ModelOptionsParams
+import com.m57.hermescontrol.data.ws.contract.RpcMethods
 import kotlinx.coroutines.CancellationException
 import kotlinx.coroutines.currentCoroutineContext
 import kotlinx.coroutines.ensureActive
@@ -16,13 +18,8 @@ class ModelOptionsRepository(
     private val connected: () -> Boolean = {
         HermesWsClient.connectionStatus.value == ConnectionStatus.CONNECTED
     },
-    private val request: suspend (Map<String, Any>) -> Any? = { params ->
-        val deferred = HermesWsClient.request(WsMethods.MODEL_OPTIONS, params)
-        try {
-            deferred.await()
-        } finally {
-            if (!deferred.isCompleted) deferred.cancel()
-        }
+    private val request: suspend (ModelOptionsParams) -> JsonElement = { params ->
+        HermesWsClient.call(RpcMethods.MODEL_OPTIONS, params)
     },
     private val rest: suspend (Boolean) -> NetworkResult<ModelOptionsResponse> = { refresh ->
         safeApiCall { ApiClient.hermesApi.getModelOptions(refresh = refresh, includeUnconfigured = false) }
@@ -32,9 +29,7 @@ class ModelOptionsRepository(
         currentCoroutineContext().ensureActive()
         if (connected()) {
             try {
-                val result = request(mapOf("refresh" to refresh, "include_unconfigured" to false))
-                // request() returns raw JsonElement, unlike the pushed-event Map representation.
-                val json = result as? JsonElement ?: error("Invalid model.options result")
+                val json = request(ModelOptionsParams(refresh = refresh, includeUnconfigured = false))
                 return NetworkResult.Success(OkHttpProvider.json.decodeFromJsonElement<ModelOptionsResponse>(json))
             } catch (e: CancellationException) {
                 // A disconnected socket may cancel the independent RPC deferred. Only fall back

app/src/main/java/com/m57/hermescontrol/data/ws/contract/ConfigModel.kt

@@ -0,0 +1,41 @@
+package com.m57.hermescontrol.data.ws.contract
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+/**
+ * `config.set` params. [key] and [value] are always encoded (no defaults); the rest are omitted
+ * when null. `profile` is injected by WsProfileParams, so it is not a field here.
+ */
+@Serializable
+data class ConfigSetParams(
+    @SerialName("key") val key: String,
+    @SerialName("value") val value: String,
+    @SerialName("session_id") val sessionId: String? = null,
+    @SerialName("scope") val scope: String? = null,
+    @SerialName("confirm_expensive_model") val confirmExpensiveModel: Boolean? = null,
+)
+
+@Serializable
+data class ConfigGetParams(
+    @SerialName("key") val key: String,
+    @SerialName("session_id") val sessionId: String? = null,
+    @SerialName("cwd") val cwd: String? = null,
+)
+
+/**
+ * `model.options` params. Flags are `Boolean?` so an explicit `false` is still sent while an
+ * unset flag is omitted (the client Json has `encodeDefaults = false`).
+ */
+@Serializable
+data class ModelOptionsParams(
+    @SerialName("session_id") val sessionId: String? = null,
+    @SerialName("explicit_only") val explicitOnly: Boolean? = null,
+    @SerialName("include_unconfigured") val includeUnconfigured: Boolean? = null,
+    @SerialName("refresh") val refresh: Boolean? = null,
+)
+
+@Serializable
+data class ClientCapabilitiesParams(
+    @SerialName("server_requests") val serverRequests: Boolean,
+)

app/src/main/java/com/m57/hermescontrol/data/ws/contract/RpcMethod.kt

@@ -395,6 +395,38 @@ object RpcMethods {
             JsonElement.serializer(),
         )
 
+    // Passthrough JsonElement results: callers keep their existing legacy decoders.
+    val CONFIG_SET: RpcMethod<ConfigSetParams, JsonElement> =
+        RpcMethod(
+            WsMethods.CONFIG_SET,
+            ConfigSetParams.serializer(),
+            JsonElement.serializer(),
+        )
+
+    // Passthrough JsonElement results: callers keep their existing legacy decoders.
+    val CONFIG_GET: RpcMethod<ConfigGetParams, JsonElement> =
+        RpcMethod(
+            WsMethods.CONFIG_GET,
+            ConfigGetParams.serializer(),
+            JsonElement.serializer(),
+        )
+
+    // Passthrough JsonElement results: callers keep their existing legacy decoders.
+    val MODEL_OPTIONS: RpcMethod<ModelOptionsParams, JsonElement> =
+        RpcMethod(
+            WsMethods.MODEL_OPTIONS,
+            ModelOptionsParams.serializer(),
+            JsonElement.serializer(),
+        )
+
+    // Passthrough JsonElement results: callers keep their existing legacy decoders.
+    val CLIENT_CAPABILITIES: RpcMethod<ClientCapabilitiesParams, JsonElement> =
+        RpcMethod(
+            WsMethods.CLIENT_CAPABILITIES,
+            ClientCapabilitiesParams.serializer(),
+            JsonElement.serializer(),
+        )
+
     /** Every typed method. GatewayContractTest iterates this; future migrations append here. */
     val all: List<RpcMethod<*, *>> =
         listOf(
@@ -446,5 +478,9 @@ object RpcMethods {
             PROJECTS_LIST,
             PROFILES_LIST,
             PROFILES_CONFIGURE,
+            CONFIG_SET,
+            CONFIG_GET,
+            MODEL_OPTIONS,
+            CLIENT_CAPABILITIES,
         )
 }

app/src/main/java/com/m57/hermescontrol/ui/chat/ChatModelSwitchDelegate.kt

@@ -12,7 +12,8 @@ import com.m57.hermescontrol.data.remote.ApiClient
 import com.m57.hermescontrol.data.remote.NetworkResult
 import com.m57.hermescontrol.data.remote.safeApiCall
 import com.m57.hermescontrol.data.ws.ModelCatalogStore
-import com.m57.hermescontrol.data.ws.WsMethods
+import com.m57.hermescontrol.data.ws.contract.ConfigSetParams
+import com.m57.hermescontrol.data.ws.contract.RpcMethods
 import com.m57.hermescontrol.data.ws.toAny
 import kotlinx.coroutines.CancellationException
 import kotlinx.coroutines.CoroutineDispatcher
@@ -51,7 +52,7 @@ class ChatModelSwitchDelegate(
     private val ioDispatcher: CoroutineDispatcher,
     private val uiState: MutableStateFlow<ChatUiState>,
     private val runtimeSessionId: () -> String?,
-    private val wsSend: (method: String, params: Map<String, Any>, onSent: ((String) -> Unit)?) -> Unit,
+    private val wsSend: (params: ConfigSetParams, onSent: ((String) -> Unit)?) -> Unit,
     private val trackRequest: (id: String, method: String) -> Unit,
     private val addAssistantMessage: (text: String) -> Unit,
     private val handleSlashCommand: (command: String) -> Unit,
@@ -64,7 +65,7 @@ class ChatModelSwitchDelegate(
         { refresh -> ModelCatalogStore.shared.ensureLoaded(forceRefresh = refresh) },
     private val getPinnedModels: () -> List<PinnedModel> = { AuthManager.getPinnedModels() },
     private val savePinnedModels: (List<PinnedModel>) -> Unit = { AuthManager.savePinnedModels(it) },
-    private val wsRequest: (suspend (method: String, params: Map<String, Any>) -> Any?)? = null,
+    private val wsRequest: (suspend (params: ConfigSetParams) -> JsonElement)? = null,
 ) {
     private val pendingModelSwitchRequests = ConcurrentHashMap<String, ActiveModelSwitch>()
     private val pendingFastSwitchRequests = ConcurrentHashMap<String, ActiveFastSwitch>()
@@ -300,20 +301,15 @@ class ChatModelSwitchDelegate(
         unconfirmedTargetModel = spec
         val switchSeq = ++modelSwitchSequence
         val params =
-            mutableMapOf<String, Any>(
-                "key" to "model",
-                "value" to spec,
-                "session_id" to sessionId,
+            ConfigSetParams(
+                key = "model",
+                value = spec,
+                sessionId = sessionId,
+                confirmExpensiveModel = true.takeIf { confirmExpensive },
             )
-        if (confirmExpensive) {
-            params["confirm_expensive_model"] = true
-        }
         scope.launch(ioDispatcher) {
-            wsSend(
-                WsMethods.CONFIG_SET,
-                params,
-            ) { id ->
-                trackRequest(id, WsMethods.CONFIG_SET)
+            wsSend(params) { id ->
+                trackRequest(id, RpcMethods.CONFIG_SET.name)
                 pendingModelSwitchRequests[id] = ActiveModelSwitch(spec, previousModel, switchSeq)
             }
         }
@@ -408,14 +404,13 @@ class ChatModelSwitchDelegate(
         uiState.update { it.copy(isFastModeChanging = true) }
         scope.launch(ioDispatcher) {
             wsSend(
-                WsMethods.CONFIG_SET,
-                mapOf(
-                    "key" to "fast",
-                    "value" to if (target) "fast" else "normal",
-                    "session_id" to sessionId,
+                ConfigSetParams(
+                    key = "fast",
+                    value = if (target) "fast" else "normal",
+                    sessionId = sessionId,
                 ),
             ) { id ->
-                trackRequest(id, WsMethods.CONFIG_SET)
+                trackRequest(id, RpcMethods.CONFIG_SET.name)
                 pendingFastSwitchRequests[id] = ActiveFastSwitch(target)
             }
         }
@@ -539,18 +534,18 @@ class ChatModelSwitchDelegate(
             scope.launch(ioDispatcher) {
                 try {
                     val params =
-                        mapOf(
-                            "key" to "reasoning",
-                            "value" to level,
-                            "session_id" to sessionId,
-                            "scope" to scopeName,
+                        ConfigSetParams(
+                            key = "reasoning",
+                            value = level,
+                            sessionId = sessionId,
+                            scope = scopeName,
                         )
                     val result =
                         if (wsRequest != null) {
-                            wsRequest.invoke(WsMethods.CONFIG_SET, params)
+                            wsRequest.invoke(params)
                         } else {
-                            wsSend(WsMethods.CONFIG_SET, params) { reqId ->
-                                trackRequest(reqId, WsMethods.CONFIG_SET)
+                            wsSend(params) { reqId ->
+                                trackRequest(reqId, RpcMethods.CONFIG_SET.name)
                             }
                             null
                         }
@@ -558,14 +553,7 @@ class ChatModelSwitchDelegate(
                     if (opSeq == reasoningOpSequence && capturedScope == dataScopeFlow.value) {
                         val ackLevel =
                             if (wsRequest != null) {
-                                // HermesWsClient.request() completes with the RAW JsonElement.
-                                // Tests and a few injected callers may provide an already-decoded map.
-                                val map =
-                                    when (result) {
-                                        is JsonElement -> result.toAny() as? Map<*, *>
-                                        is Map<*, *> -> result
-                                        else -> null
-                                    }
+                                val map = result?.toAny() as? Map<*, *>
                                 val resKey = map?.get("key") as? String
                                 val resVal = map?.get("value") as? String
                                 if (resKey != "reasoning" || resVal.isNullOrEmpty()) {

app/src/main/java/com/m57/hermescontrol/ui/chat/ChatViewModel.kt

@@ -37,6 +37,8 @@ import com.m57.hermescontrol.data.ws.HermesWsClient
 import com.m57.hermescontrol.data.ws.JsonRpcError
 import com.m57.hermescontrol.data.ws.WsEvent
 import com.m57.hermescontrol.data.ws.WsMethods
+import com.m57.hermescontrol.data.ws.contract.ConfigGetParams
+import com.m57.hermescontrol.data.ws.contract.ConfigSetParams
 import com.m57.hermescontrol.data.ws.contract.PromptBtwParams
 import com.m57.hermescontrol.data.ws.contract.RpcMethod
 import com.m57.hermescontrol.data.ws.contract.RpcMethods
@@ -694,13 +696,13 @@ class ChatViewModel(
             ioDispatcher = ioDispatcher,
             uiState = _uiState,
             runtimeSessionId = { runtimeSessionId },
-            wsSend = { method, params, onSent -> wsClient.send(method, params, onSent) },
+            wsSend = { params, onSent -> wsClient.send(RpcMethods.CONFIG_SET, params, onSent) },
             trackRequest = { id, method -> trackRequest(id, method) },
             addAssistantMessage = { text -> addAssistantMessage(text) },
             handleSlashCommand = { cmd -> handleSlashCommand(cmd) },
             fetchContextUsage = { fetchContextUsage() },
             onModelSwitchInitiated = { onModelSwitchInitiated() },
-            wsRequest = { method, params -> wsClient.request(method, params).await() },
+            wsRequest = { params -> wsClient.call(RpcMethods.CONFIG_SET, params) },
         ).apply {
             attachScopeObserver(viewModelScope)
         }
@@ -3846,14 +3848,10 @@ class ChatViewModel(
             viewModelScope.launch(ioDispatcher) {
                 try {
                     val result =
-                        wsClient
-                            .request(
-                                WsMethods.CONFIG_GET,
-                                mapOf(
-                                    "key" to "reasoning",
-                                    "session_id" to sessionId,
-                                ),
-                            ).await()
+                        wsClient.call(
+                            RpcMethods.CONFIG_GET,
+                            ConfigGetParams(key = "reasoning", sessionId = sessionId),
+                        )
                     val map = rpcResultMap(result) ?: error("Invalid reasoning config.get response")
                     val value = (map["value"] as? String)?.takeIf { it.isNotBlank() } ?: "unknown"
                     val display = (map["display"] as? String)?.takeIf { it.isNotBlank() } ?: "unknown"
@@ -3901,13 +3899,13 @@ class ChatViewModel(
         viewModelScope.launch(ioDispatcher) {
             try {
                 val params =
-                    buildMap<String, Any> {
-                        put("key", "reasoning")
-                        put("value", parsed.value)
-                        put("session_id", sessionId)
-                        parsed.scopeName?.let { put("scope", it) }
-                    }
-                val result = wsClient.request(WsMethods.CONFIG_SET, params).await()
+                    ConfigSetParams(
+                        key = "reasoning",
+                        value = parsed.value,
+                        sessionId = sessionId,
+                        scope = parsed.scopeName,
+                    )
+                val result = wsClient.call(RpcMethods.CONFIG_SET, params)
                 val map = rpcResultMap(result) ?: error("Invalid reasoning config.set response")
                 val responseKey = map["key"] as? String
                 val responseValue = map["value"] as? String

app/src/test/java/com/m57/hermescontrol/data/ws/ModelOptionsRepositoryTest.kt

@@ -2,6 +2,7 @@ package com.m57.hermescontrol.data.ws
 
 import com.m57.hermescontrol.data.model.ModelOptionsResponse
 import com.m57.hermescontrol.data.remote.NetworkResult
+import com.m57.hermescontrol.data.ws.contract.ModelOptionsParams
 import kotlinx.coroutines.CompletableDeferred
 import kotlinx.coroutines.async
 import kotlinx.coroutines.awaitCancellation
@@ -21,7 +22,7 @@ class ModelOptionsRepositoryTest {
                 ModelOptionsRepository(
                     connected = { true },
                     request = { params ->
-                        assertEquals(mapOf("refresh" to true, "include_unconfigured" to false), params)
+                        assertEquals(ModelOptionsParams(refresh = true, includeUnconfigured = false), params)
                         Json.parseToJsonElement("""{"providers":[{"slug":"test","name":"Test","models":["a"]}]}""")
                     },
                     rest = { error("REST must not run") },

app/src/test/java/com/m57/hermescontrol/data/ws/RawRpcParamsRatchetTest.kt

@@ -316,17 +316,9 @@ class RawRpcParamsRatchetTest {
          */
         val BASELINE: List<String> =
             listOf(
-                "data/ws/HermesWsClient.kt::CLIENT_CAPABILITIES",
-                "data/ws/ModelOptionsRepository.kt::MODEL_OPTIONS",
-                "ui/chat/ChatModelSwitchDelegate.kt::CONFIG_SET",
-                "ui/chat/ChatModelSwitchDelegate.kt::CONFIG_SET",
-                "ui/chat/ChatModelSwitchDelegate.kt::CONFIG_SET",
-                "ui/chat/ChatModelSwitchDelegate.kt::CONFIG_SET",
                 "ui/chat/ChatViewModel.kt::COMMANDS_CATALOG",
                 "ui/chat/ChatViewModel.kt::COMMAND_DISPATCH",
                 "ui/chat/ChatViewModel.kt::COMMAND_DISPATCH",
-                "ui/chat/ChatViewModel.kt::CONFIG_GET",
-                "ui/chat/ChatViewModel.kt::CONFIG_SET",
                 "ui/chat/ChatViewModel.kt::FILE_ATTACH",
                 "ui/chat/ChatViewModel.kt::IMAGE_ATTACH_BYTES",
                 "ui/chat/ChatViewModel.kt::SLASH_EXEC",

app/src/test/java/com/m57/hermescontrol/data/ws/contract/ConfigModelTypesTest.kt

@@ -0,0 +1,102 @@
+package com.m57.hermescontrol.data.ws.contract
+
+import com.m57.hermescontrol.data.remote.OkHttpProvider
+import kotlinx.serialization.json.buildJsonObject
+import kotlinx.serialization.json.put
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class ConfigModelTypesTest {
+    private val json = OkHttpProvider.json
+
+    @Test
+    fun configSetEncodesOnlyKeyAndValueByDefault() {
+        assertEquals(
+            buildJsonObject {
+                put("key", "fast")
+                put("value", "normal")
+            },
+            json.encodeToJsonElement(ConfigSetParams.serializer(), ConfigSetParams(key = "fast", value = "normal")),
+        )
+    }
+
+    @Test
+    fun configSetEncodesSessionScopeAndConfirmWhenPresent() {
+        assertEquals(
+            buildJsonObject {
+                put("key", "model")
+                put("value", "gpt-4o --provider openai --session")
+                put("session_id", "s1")
+                put("scope", "global")
+                put("confirm_expensive_model", true)
+            },
+            json.encodeToJsonElement(
+                ConfigSetParams.serializer(),
+                ConfigSetParams(
+                    key = "model",
+                    value = "gpt-4o --provider openai --session",
+                    sessionId = "s1",
+                    scope = "global",
+                    confirmExpensiveModel = true,
+                ),
+            ),
+        )
+    }
+
+    @Test
+    fun configGetOmitsNullSessionAndCwd() {
+        assertEquals(
+            buildJsonObject {
+                put("key", "reasoning")
+                put("session_id", "s1")
+            },
+            json.encodeToJsonElement(
+                ConfigGetParams.serializer(),
+                ConfigGetParams(key = "reasoning", sessionId = "s1"),
+            ),
+        )
+    }
+
+    @Test
+    fun modelOptionsKeepsExplicitFalseAndOmitsUnsetFlags() {
+        assertEquals(
+            buildJsonObject {
+                put("refresh", true)
+                put("include_unconfigured", false)
+            },
+            json.encodeToJsonElement(
+                ModelOptionsParams.serializer(),
+                ModelOptionsParams(refresh = true, includeUnconfigured = false),
+            ),
+        )
+        assertEquals(
+            buildJsonObject { },
+            json.encodeToJsonElement(ModelOptionsParams.serializer(), ModelOptionsParams()),
+        )
+    }
+
+    @Test
+    fun clientCapabilitiesAlwaysEncodesServerRequests() {
+        assertEquals(
+            buildJsonObject { put("server_requests", true) },
+            json.encodeToJsonElement(
+                ClientCapabilitiesParams.serializer(),
+                ClientCapabilitiesParams(serverRequests = true),
+            ),
+        )
+    }
+
+    @Test
+    fun descriptorsAreRegisteredWithContractNames() {
+        listOf(
+            RpcMethods.CONFIG_SET to "config.set",
+            RpcMethods.CONFIG_GET to "config.get",
+            RpcMethods.MODEL_OPTIONS to "model.options",
+            RpcMethods.CLIENT_CAPABILITIES to "client.capabilities",
+        ).forEach { (method, name) ->
+            assertTrue("$name not in RpcMethods.all", method in RpcMethods.all)
+            assertEquals(name, method.name)
+        }
+    }
+}

app/src/test/java/com/m57/hermescontrol/ui/chat/ChatModelSwitchDelegateTest.kt

@@ -8,7 +8,7 @@ import com.m57.hermescontrol.data.model.ModelProvider
 import com.m57.hermescontrol.data.model.PinnedModel
 import com.m57.hermescontrol.data.remote.NetworkError
 import com.m57.hermescontrol.data.remote.NetworkResult
-import com.m57.hermescontrol.data.ws.WsMethods
+import com.m57.hermescontrol.data.ws.contract.ConfigSetParams
 import kotlinx.coroutines.CompletableDeferred
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.flow.MutableStateFlow
@@ -18,6 +18,8 @@ import kotlinx.coroutines.test.TestScope
 import kotlinx.coroutines.test.advanceUntilIdle
 import kotlinx.coroutines.test.runCurrent
 import kotlinx.coroutines.test.runTest
+import kotlinx.serialization.json.JsonElement
+import kotlinx.serialization.json.JsonNull
 import org.junit.Assert.assertEquals
 import org.junit.Assert.assertFalse
 import org.junit.Assert.assertNull
@@ -31,8 +33,7 @@ class ChatModelSwitchDelegateTest {
     private val uiState =
         MutableStateFlow(ChatUiState(currentSessionId = "sess-1", currentSessionModel = "anthropic/claude-3"))
     private var runtimeId: String? = "runtime-1"
-    private val sentMethods = mutableListOf<String>()
-    private val sentParams = mutableListOf<Map<String, Any>>()
+    private val sentParams = mutableListOf<ConfigSetParams>()
     private val slashCommands = mutableListOf<String>()
     private val assistantMessages = mutableListOf<String>()
     private var contextRefetched = 0
@@ -71,10 +72,9 @@ class ChatModelSwitchDelegateTest {
             ioDispatcher = testDispatcher,
             uiState = uiState,
             runtimeSessionId = { runtimeId },
-            wsSend = { method, params, onSent ->
-                sentMethods.add(method)
+            wsSend = { params, onSent ->
                 sentParams.add(params)
-                onSent?.invoke("req-${sentMethods.size}")
+                onSent?.invoke("req-${sentParams.size}")
             },
             trackRequest = { _, _ -> },
             addAssistantMessage = { assistantMessages.add(it) },
@@ -304,8 +304,9 @@ class ChatModelSwitchDelegateTest {
             delegate.handleModelSwitch("/MODEL gpt-4o --provider openai --session")
             advanceUntilIdle()
 
-            assertEquals(listOf(WsMethods.CONFIG_SET), sentMethods)
-            assertEquals("gpt-4o --provider openai --session", sentParams.first()["value"])
+            assertEquals(1, sentParams.size)
+            assertEquals("model", sentParams.first().key)
+            assertEquals("gpt-4o --provider openai --session", sentParams.first().value)
 
             delegate.handleConfigSetResult(
                 id = "req-1",
@@ -320,8 +321,8 @@ class ChatModelSwitchDelegateTest {
 
             delegate.confirmModelSwitchExpensive()
             advanceUntilIdle()
-            assertEquals(2, sentMethods.size)
-            assertEquals(true, sentParams[1]["confirm_expensive_model"])
+            assertEquals(2, sentParams.size)
+            assertEquals(true, sentParams[1].confirmExpensiveModel)
         }
 
     @Test
@@ -366,7 +367,6 @@ class ChatModelSwitchDelegateTest {
             // Switch to model with fast capability
             delegate.sendSlashModel("openai", "gpt-4o")
             advanceUntilIdle()
-            sentMethods.clear()
             sentParams.clear()
 
             assertTrue(uiState.value.currentModelCapabilities?.fast == true)
@@ -377,10 +377,10 @@ class ChatModelSwitchDelegateTest {
             advanceUntilIdle()
             assertTrue(uiState.value.isFastModeChanging)
             assertFalse(uiState.value.fastMode) // Still unconfirmed!
-            assertEquals(listOf(WsMethods.CONFIG_SET), sentMethods)
-            assertEquals("fast", sentParams.first()["key"])
-            assertEquals("fast", sentParams.first()["value"])
-            assertEquals("runtime-1", sentParams.first()["session_id"])
+            assertEquals(1, sentParams.size)
+            assertEquals("fast", sentParams.first().key)
+            assertEquals("fast", sentParams.first().value)
+            assertEquals("runtime-1", sentParams.first().sessionId)
 
             // Backend acknowledges
             delegate.handleConfigSetResult("req-1", mapOf("key" to "fast", "value" to "fast"))
@@ -391,7 +391,7 @@ class ChatModelSwitchDelegateTest {
             delegate.toggleFastMode()
             advanceUntilIdle()
             assertTrue(uiState.value.isFastModeChanging)
-            assertEquals("normal", sentParams.last()["value"])
+            assertEquals("normal", sentParams.last().value)
 
             delegate.handleConfigSetResult("req-2", mapOf("key" to "fast", "value" to "normal"))
             assertFalse(uiState.value.fastMode)
@@ -405,7 +405,6 @@ class ChatModelSwitchDelegateTest {
             advanceUntilIdle()
             delegate.sendSlashModel("openai", "gpt-4o")
             advanceUntilIdle()
-            sentMethods.clear()
             sentParams.clear()
             assertTrue(uiState.value.currentModelCapabilities?.fast == true)
 
@@ -420,10 +419,10 @@ class ChatModelSwitchDelegateTest {
             assertEquals(false, uiState.value.currentModelCapabilities?.fast)
 
             // Further toggle attempts are no-ops
-            val sentCount = sentMethods.size
+            val sentCount = sentParams.size
             delegate.toggleFastMode()
             advanceUntilIdle()
-            assertEquals(sentCount, sentMethods.size)
+            assertEquals(sentCount, sentParams.size)
         }
 
     @Test
@@ -470,9 +469,8 @@ class ChatModelSwitchDelegateTest {
     @Test
     fun setReasoningLevel_awaitsRequest_updatesOnAck_andPreventsConcurrentPick() =
         testScope.runTest {
-            val gate = CompletableDeferred<Any?>()
-            val reqMethods = mutableListOf<String>()
-            val reqParams = mutableListOf<Map<String, Any>>()
+            val gate = CompletableDeferred<JsonElement>()
+            val reqParams = mutableListOf<ConfigSetParams>()
 
             val customDelegate =
                 ChatModelSwitchDelegate(
@@ -480,14 +478,13 @@ class ChatModelSwitchDelegateTest {
                     ioDispatcher = testDispatcher,
                     uiState = uiState,
                     runtimeSessionId = { runtimeId },
-                    wsSend = { _, _, _ -> },
+                    wsSend = { _, _ -> },
                     trackRequest = { _, _ -> },
                     addAssistantMessage = {},
                     handleSlashCommand = {},
                     fetchContextUsage = {},
                     dataScopeFlow = dataScope,
-                    wsRequest = { method, params ->
-                        reqMethods.add(method)
+                    wsRequest = { params ->
                         reqParams.add(params)
                         gate.await()
                     },
@@ -503,14 +500,15 @@ class ChatModelSwitchDelegateTest {
             assertEquals("ultra", uiState.value.reasoningLevel)
             assertEquals("high", uiState.value.pendingReasoningLevel)
             assertNull(uiState.value.reasoningWireLevel)
-            assertEquals(listOf(WsMethods.CONFIG_SET), reqMethods)
-            assertEquals("session", reqParams.first()["scope"])
-            assertEquals("high", reqParams.first()["value"])
+            assertEquals(1, reqParams.size)
+            assertEquals("reasoning", reqParams.first().key)
+            assertEquals("session", reqParams.first().scope)
+            assertEquals("high", reqParams.first().value)
 
             // Second pick while in-flight is rejected (serialized)
             customDelegate.setReasoningLevel("low")
             runCurrent()
-            assertEquals(1, reqMethods.size)
+            assertEquals(1, reqParams.size)
 
             // Simulate session.info winning the race and publishing the fresh
             // authoritative wire before the RPC ACK resumes the delegate.
@@ -540,13 +538,13 @@ class ChatModelSwitchDelegateTest {
                     ioDispatcher = testDispatcher,
                     uiState = uiState,
                     runtimeSessionId = { runtimeId },
-                    wsSend = { _, _, _ -> },
+                    wsSend = { _, _ -> },
                     trackRequest = { _, _ -> },
                     addAssistantMessage = {},
                     handleSlashCommand = {},
                     fetchContextUsage = {},
                     dataScopeFlow = dataScope,
-                    wsRequest = { _, _ -> throw RuntimeException("4002 unknown reasoning value") },
+                    wsRequest = { throw RuntimeException("4002 unknown reasoning value") },
                 )
 
             customDelegate.setReasoningLevel("ultra")
@@ -560,7 +558,7 @@ class ChatModelSwitchDelegateTest {
     @Test
     fun setReasoningLevel_whenRuntimeSessionNullOrBlank_doesNotSend() =
         testScope.runTest {
-            val reqMethods = mutableListOf<String>()
+            val reqParams = mutableListOf<ConfigSetParams>()
             runtimeId = null
 
             val customDelegate =
@@ -569,22 +567,22 @@ class ChatModelSwitchDelegateTest {
                     ioDispatcher = testDispatcher,
                     uiState = uiState,
                     runtimeSessionId = { runtimeId },
-                    wsSend = { _, _, _ -> },
+                    wsSend = { _, _ -> },
                     trackRequest = { _, _ -> },
                     addAssistantMessage = {},
                     handleSlashCommand = {},
                     fetchContextUsage = {},
                     dataScopeFlow = dataScope,
-                    wsRequest = { method, _ ->
-                        reqMethods.add(method)
-                        null
+                    wsRequest = { params ->
+                        reqParams.add(params)
+                        JsonNull
                     },
                 )
 
             customDelegate.setReasoningLevel("high")
             advanceUntilIdle()
 
-            assertTrue(reqMethods.isEmpty())
+            assertTrue(reqParams.isEmpty())
             assertNull(uiState.value.pendingReasoningLevel)
             assertNull(uiState.value.reasoningLevel)
         }
@@ -592,20 +590,20 @@ class ChatModelSwitchDelegateTest {
     @Test
     fun setReasoningLevel_staleScopeOrReset_dropsLateAck() =
         testScope.runTest {
-            val gate = CompletableDeferred<Any?>()
+            val gate = CompletableDeferred<JsonElement>()
             val customDelegate =
                 ChatModelSwitchDelegate(
                     scope = testScope,
                     ioDispatcher = testDispatcher,
                     uiState = uiState,
                     runtimeSessionId = { runtimeId },
-                    wsSend = { _, _, _ -> },
+                    wsSend = { _, _ -> },
                     trackRequest = { _, _ -> },
                     addAssistantMessage = {},
                     handleSlashCommand = {},
                     fetchContextUsage = {},
                     dataScopeFlow = dataScope,
-                    wsRequest = { _, _ -> gate.await() },
+                    wsRequest = { gate.await() },
                 )
 
             customDelegate.setReasoningLevel("high")
@@ -617,7 +615,12 @@ class ChatModelSwitchDelegateTest {
             assertNull(uiState.value.pendingReasoningLevel)
 
             // Late RPC response arrives
-            gate.complete(mapOf("key" to "reasoning", "value" to "high"))
+            gate.complete(
+                kotlinx.serialization.json.buildJsonObject {
+                    put("key", kotlinx.serialization.json.JsonPrimitive("reasoning"))
+                    put("value", kotlinx.serialization.json.JsonPrimitive("high"))
+                },
+            )
             advanceUntilIdle()
 
             assertNull(uiState.value.reasoningLevel)

app/src/test/java/com/m57/hermescontrol/ui/chat/ChatViewModelTest.kt

@@ -35,6 +35,8 @@ import com.m57.hermescontrol.data.ws.JsonRpcError
 import com.m57.hermescontrol.data.ws.ModelCatalogStore
 import com.m57.hermescontrol.data.ws.WsEvent
 import com.m57.hermescontrol.data.ws.WsMethods
+import com.m57.hermescontrol.data.ws.contract.ConfigSetParams
+import com.m57.hermescontrol.data.ws.contract.RpcMethods
 import com.m57.hermescontrol.notification.TurnCorrelationTracker
 import com.m57.hermescontrol.ui.chat.fakes.FakeChatPersistenceRepository
 import com.m57.hermescontrol.ui.chat.fakes.FakeSlashUsageStore
@@ -1295,15 +1297,9 @@ class ChatViewModelTest {
             // commands). NOT command.dispatch (4018s on /model), NOT prompt.submit
             // (LLM would treat it as text). Capture the config.set params.
             val modelCalls = mutableListOf<Triple<String, String, String>>()
-            every { HermesWsClient.send(WsMethods.CONFIG_SET, any(), any()) } answers {
-                val params = arg<Map<String, Any>>(1)
-                modelCalls.add(
-                    Triple(
-                        params["key"] as String,
-                        params["value"] as String,
-                        params["session_id"] as String,
-                    ),
-                )
+            every { HermesWsClient.send(RpcMethods.CONFIG_SET, any<ConfigSetParams>(), any()) } answers {
+                val params = arg<ConfigSetParams>(1)
+                modelCalls.add(Triple(params.key, params.value, params.sessionId.orEmpty()))
                 "req-cfg-${modelCalls.size}"
             }
 
@@ -1315,7 +1311,7 @@ class ChatViewModelTest {
                 "openai/gpt-4o",
                 viewModel.uiState.value.currentSessionModel,
             )
-            verify { HermesWsClient.send(WsMethods.CONFIG_SET, any(), any()) }
+            verify { HermesWsClient.send(RpcMethods.CONFIG_SET, any<ConfigSetParams>(), any()) }
             val call = modelCalls.firstOrNull { it.first == "model" }
             assertNotNull("selection must route through config.set key=model", call)
             assertEquals("gpt-4o --provider openai --session", call!!.second)
@@ -1340,7 +1336,7 @@ class ChatViewModelTest {
             // (key="model"), which the gateway routes to _apply_model_switch. NOT
             // command.dispatch (4018s on /model) and NOT prompt.submit (LLM would
             // treat it as text).
-            verify { HermesWsClient.send(WsMethods.CONFIG_SET, any(), any()) }
+            verify { HermesWsClient.send(RpcMethods.CONFIG_SET, any<ConfigSetParams>(), any()) }
         }
 
     @Test
@@ -1353,15 +1349,9 @@ class ChatViewModelTest {
             // slash prefix must be stripped, or parse_model_flags on the
             // backend won't recognize it and the hot-swap silently fails.
             val modelCalls = mutableListOf<Triple<String, String, String>>()
-            every { HermesWsClient.send(WsMethods.CONFIG_SET, any(), any()) } answers {
-                val params = arg<Map<String, Any>>(1)
-                modelCalls.add(
-                    Triple(
-                        params["key"] as String,
-                        params["value"] as String,
-                        params["session_id"] as String,
-                    ),
-                )
+            every { HermesWsClient.send(RpcMethods.CONFIG_SET, any<ConfigSetParams>(), any()) } answers {
+                val params = arg<ConfigSetParams>(1)
+                modelCalls.add(Triple(params.key, params.value, params.sessionId.orEmpty()))
                 "req-cfg-ci-${modelCalls.size}"
             }
 
@@ -1388,9 +1378,9 @@ class ChatViewModelTest {
             val (viewModel, sessionId) = createViewModelWithSession()
 
             var lastReqId = ""
-            val capturedParams = mutableListOf<Map<String, Any>>()
-            every { HermesWsClient.send(WsMethods.CONFIG_SET, any(), any()) } answers {
-                val params = arg<Map<String, Any>>(1)
+            val capturedParams = mutableListOf<ConfigSetParams>()
+            every { HermesWsClient.send(RpcMethods.CONFIG_SET, any<ConfigSetParams>(), any()) } answers {
+                val params = arg<ConfigSetParams>(1)
                 capturedParams.add(params)
                 val id = "req-confirm-${capturedParams.size}"
                 lastReqId = id
@@ -1403,7 +1393,7 @@ class ChatViewModelTest {
             advanceUntilIdle()
 
             assertEquals(1, capturedParams.size)
-            assertNull(capturedParams[0]["confirm_expensive_model"])
+            assertNull(capturedParams[0].confirmExpensiveModel)
 
             // Backend returns confirm_required = true
             mockEventsFlow.emit(
@@ -1429,12 +1419,12 @@ class ChatViewModelTest {
 
             assertNull(viewModel.uiState.value.modelSwitchConfirmMessage)
             assertEquals(2, capturedParams.size)
-            assertEquals(true, capturedParams[1]["confirm_expensive_model"])
+            assertEquals(true, capturedParams[1].confirmExpensiveModel)
             assertEquals(
                 "muse-spark-1.3-contributor-free --provider opencode-free --session",
-                capturedParams[1]["value"],
+                capturedParams[1].value,
             )
-            assertEquals(sessionId, capturedParams[1]["session_id"])
+            assertEquals(sessionId, capturedParams[1].sessionId)
         }
 
     @Test
@@ -1443,7 +1433,7 @@ class ChatViewModelTest {
             val (viewModel, _) = createViewModelWithSession()
 
             var lastReqId = ""
-            every { HermesWsClient.send(WsMethods.CONFIG_SET, any(), any()) } answers {
+            every { HermesWsClient.send(RpcMethods.CONFIG_SET, any<ConfigSetParams>(), any()) } answers {
                 val id = "req-cfg-dismiss"
                 lastReqId = id
                 arg<((String) -> Unit)?>(2)?.invoke(id)

app/src/test/java/com/m57/hermescontrol/ui/chat/SlashCommandDispatchRpcTest.kt

@@ -12,6 +12,9 @@ import com.m57.hermescontrol.data.ws.ConnectionStatus
 import com.m57.hermescontrol.data.ws.HermesWsClient
 import com.m57.hermescontrol.data.ws.WsEvent
 import com.m57.hermescontrol.data.ws.WsMethods
+import com.m57.hermescontrol.data.ws.contract.ConfigGetParams
+import com.m57.hermescontrol.data.ws.contract.ConfigSetParams
+import com.m57.hermescontrol.data.ws.contract.RpcMethods
 import com.m57.hermescontrol.ui.chat.fakes.FakeChatPersistenceRepository
 import com.m57.hermescontrol.ui.chat.fakes.FakeSlashUsageStore
 import io.mockk.coEvery
@@ -21,6 +24,7 @@ import io.mockk.mockkObject
 import io.mockk.mockkStatic
 import io.mockk.slot
 import io.mockk.unmockkAll
+import io.mockk.verify
 import kotlinx.coroutines.CompletableDeferred
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.ExperimentalCoroutinesApi
@@ -34,6 +38,7 @@ import kotlinx.coroutines.test.runTest
 import kotlinx.coroutines.test.setMain
 import org.junit.After
 import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
 import org.junit.Assert.assertTrue
 import org.junit.Before
 import org.junit.Test
@@ -271,35 +276,27 @@ class SlashCommandDispatchRpcTest {
         runTest {
             val (vm, sessionId) = createViewModelWithSession()
 
-            val methodCalls = mutableListOf<String>()
-            val paramsCalls = mutableListOf<Map<String, Any>>()
-            every {
-                HermesWsClient.request(capture(methodCalls), capture(paramsCalls), any())
+            val setCalls = mutableListOf<ConfigSetParams>()
+            coEvery {
+                HermesWsClient.call(RpcMethods.CONFIG_SET, capture(setCalls), any(), any())
             } answers {
-                val result =
-                    if (arg<String>(0) == WsMethods.CONFIG_SET) {
-                        kotlinx.serialization.json.buildJsonObject {
-                            put("key", kotlinx.serialization.json.JsonPrimitive("reasoning"))
-                            put("value", kotlinx.serialization.json.JsonPrimitive("high"))
-                        }
-                    } else {
-                        kotlinx.serialization.json.JsonNull
-                    }
-                CompletableDeferred<Any?>(result)
+                kotlinx.serialization.json.buildJsonObject {
+                    put("key", kotlinx.serialization.json.JsonPrimitive("reasoning"))
+                    put("value", kotlinx.serialization.json.JsonPrimitive("high"))
+                }
             }
 
             vm.sendMessage("/reasoning high --global")
             advanceUntilIdle()
 
-            val configIndex = methodCalls.indexOf(WsMethods.CONFIG_SET)
-            assertTrue("expected CONFIG_SET, got $methodCalls", configIndex >= 0)
-            val params = paramsCalls[configIndex]
-            assertEquals("reasoning", params["key"])
-            assertEquals("high", params["value"])
-            assertEquals(sessionId, params["session_id"])
-            assertEquals("global", params["scope"])
+            assertEquals("expected exactly one config.set, got $setCalls", 1, setCalls.size)
+            val params = setCalls.single()
+            assertEquals("reasoning", params.key)
+            assertEquals("high", params.value)
+            assertEquals(sessionId, params.sessionId)
+            assertEquals("global", params.scope)
             assertEquals("high", vm.uiState.value.reasoningLevel)
-            assertTrue(WsMethods.COMMAND_DISPATCH !in methodCalls)
+            verify(exactly = 0) { HermesWsClient.send(WsMethods.COMMAND_DISPATCH, any(), any()) }
         }
 
     @Test
@@ -307,33 +304,26 @@ class SlashCommandDispatchRpcTest {
         runTest {
             val (vm, sessionId) = createViewModelWithSession()
 
-            val methodCalls = mutableListOf<String>()
-            val paramsCalls = mutableListOf<Map<String, Any>>()
-            every {
-                HermesWsClient.request(capture(methodCalls), capture(paramsCalls), any())
+            val setCalls = mutableListOf<ConfigSetParams>()
+            coEvery {
+                HermesWsClient.call(RpcMethods.CONFIG_SET, capture(setCalls), any(), any())
             } answers {
-                val result =
-                    if (arg<String>(0) == WsMethods.CONFIG_SET) {
-                        kotlinx.serialization.json.buildJsonObject {
-                            put("key", kotlinx.serialization.json.JsonPrimitive("reasoning"))
-                            put("value", kotlinx.serialization.json.JsonPrimitive("show"))
-                        }
-                    } else {
-                        kotlinx.serialization.json.JsonNull
-                    }
-                CompletableDeferred<Any?>(result)
+                kotlinx.serialization.json.buildJsonObject {
+                    put("key", kotlinx.serialization.json.JsonPrimitive("reasoning"))
+                    put("value", kotlinx.serialization.json.JsonPrimitive("show"))
+                }
             }
 
             vm.sendMessage("/reasoning show")
             advanceUntilIdle()
 
-            val configIndex = methodCalls.indexOf(WsMethods.CONFIG_SET)
-            assertTrue("expected CONFIG_SET, got $methodCalls", configIndex >= 0)
-            val params = paramsCalls[configIndex]
-            assertEquals("reasoning", params["key"])
-            assertEquals("show", params["value"])
-            assertEquals(sessionId, params["session_id"])
-            assertTrue(WsMethods.COMMAND_DISPATCH !in methodCalls)
+            assertEquals("expected exactly one config.set, got $setCalls", 1, setCalls.size)
+            val params = setCalls.single()
+            assertEquals("reasoning", params.key)
+            assertEquals("show", params.value)
+            assertEquals(sessionId, params.sessionId)
+            assertNull(params.scope)
+            verify(exactly = 0) { HermesWsClient.send(WsMethods.COMMAND_DISPATCH, any(), any()) }
             assertEquals(
                 "reasoning: show",
                 vm.uiState.value.messages
@@ -347,32 +337,24 @@ class SlashCommandDispatchRpcTest {
         runTest {
             val (vm, sessionId) = createViewModelWithSession()
 
-            val methodCalls = mutableListOf<String>()
-            val paramsCalls = mutableListOf<Map<String, Any>>()
-            every {
-                HermesWsClient.request(capture(methodCalls), capture(paramsCalls), any())
+            val getCalls = mutableListOf<ConfigGetParams>()
+            coEvery {
+                HermesWsClient.call(RpcMethods.CONFIG_GET, capture(getCalls), any(), any())
             } answers {
-                val result =
-                    if (arg<String>(0) == WsMethods.CONFIG_GET) {
-                        kotlinx.serialization.json.buildJsonObject {
-                            put("value", kotlinx.serialization.json.JsonPrimitive("ultra"))
-                            put("display", kotlinx.serialization.json.JsonPrimitive("hide"))
-                        }
-                    } else {
-                        kotlinx.serialization.json.JsonNull
-                    }
-                CompletableDeferred<Any?>(result)
+                kotlinx.serialization.json.buildJsonObject {
+                    put("value", kotlinx.serialization.json.JsonPrimitive("ultra"))
+                    put("display", kotlinx.serialization.json.JsonPrimitive("hide"))
+                }
             }
 
             vm.sendMessage("/reasoning")
             advanceUntilIdle()
 
-            val configIndex = methodCalls.indexOf(WsMethods.CONFIG_GET)
-            assertTrue("expected CONFIG_GET, got $methodCalls", configIndex >= 0)
-            val params = paramsCalls[configIndex]
-            assertEquals("reasoning", params["key"])
-            assertEquals(sessionId, params["session_id"])
-            assertTrue(WsMethods.COMMAND_DISPATCH !in methodCalls)
+            assertEquals("expected exactly one config.get, got $getCalls", 1, getCalls.size)
+            val params = getCalls.single()
+            assertEquals("reasoning", params.key)
+            assertEquals(sessionId, params.sessionId)
+            verify(exactly = 0) { HermesWsClient.send(WsMethods.COMMAND_DISPATCH, any(), any()) }
             assertEquals(
                 "reasoning: ultra · display hide",
                 vm.uiState.value.messages