[goose-llm] system prompt override (#2791)

bindings/kotlin/example/Usage.kt

@@ -130,8 +130,8 @@ fun main() = runBlocking {
         providerConfig,
         modelConfig,
         systemPreamble,
-        msgs,
-        extensions
+        messages = msgs,
+        extensions = extensions
     )
 
     val response = completion(req)
@@ -140,6 +140,32 @@ fun main() = runBlocking {
 
     // ---- UI Extraction (custom schema) ----
     runUiExtraction(providerName, providerConfig)
+
+
+    // --- Prompt Override ---
+    val prompt_req = createCompletionRequest(
+        providerName,
+        providerConfig,
+        modelConfig,
+        systemPreamble = null, 
+        systemPromptOverride = "You are a bot named Tile Creator. Your task is to create a tile based on the user's input.",
+        messages=listOf(
+            Message(
+                role    = Role.USER,
+                created = now,
+                content = listOf(
+                    MessageContent.Text(
+                        TextContent("What's your name?")
+                    )
+                )
+            )
+        ),
+        extensions=emptyList()
+    )
+
+    val prompt_resp = completion(prompt_req)
+
+    println("\nPrompt Override Response:\n${prompt_resp.message}")
 }
 
 

bindings/kotlin/uniffi/goose_llm/goose_llm.kt

@@ -830,6 +830,7 @@ internal interface UniffiLib : Library {
         `providerConfig`: RustBuffer.ByValue,
         `modelConfig`: RustBuffer.ByValue,
         `systemPreamble`: RustBuffer.ByValue,
+        `systemPromptOverride`: RustBuffer.ByValue,
         `messages`: RustBuffer.ByValue,
         `extensions`: RustBuffer.ByValue,
         uniffi_out_err: UniffiRustCallStatus,
@@ -1100,7 +1101,7 @@ private fun uniffiCheckApiChecksums(lib: IntegrityCheckingUniffiLib) {
     if (lib.uniffi_goose_llm_checksum_func_completion() != 47457.toShort()) {
         throw RuntimeException("UniFFI API checksum mismatch: try cleaning and rebuilding your project")
     }
-    if (lib.uniffi_goose_llm_checksum_func_create_completion_request() != 39068.toShort()) {
+    if (lib.uniffi_goose_llm_checksum_func_create_completion_request() != 50798.toShort()) {
         throw RuntimeException("UniFFI API checksum mismatch: try cleaning and rebuilding your project")
     }
     if (lib.uniffi_goose_llm_checksum_func_create_tool_config() != 49910.toShort()) {
@@ -2955,7 +2956,8 @@ fun `createCompletionRequest`(
     `providerName`: kotlin.String,
     `providerConfig`: Value,
     `modelConfig`: ModelConfig,
-    `systemPreamble`: kotlin.String,
+    `systemPreamble`: kotlin.String? = null,
+    `systemPromptOverride`: kotlin.String? = null,
     `messages`: List<Message>,
     `extensions`: List<ExtensionConfig>,
 ): CompletionRequest =
@@ -2965,7 +2967,8 @@ fun `createCompletionRequest`(
                 FfiConverterString.lower(`providerName`),
                 FfiConverterTypeValue.lower(`providerConfig`),
                 FfiConverterTypeModelConfig.lower(`modelConfig`),
-                FfiConverterString.lower(`systemPreamble`),
+                FfiConverterOptionalString.lower(`systemPreamble`),
+                FfiConverterOptionalString.lower(`systemPromptOverride`),
                 FfiConverterSequenceTypeMessage.lower(`messages`),
                 FfiConverterSequenceTypeExtensionConfig.lower(`extensions`),
                 _status,