Configure STT language from settings (#941)

* Configure STT language from settings

* Update websocket speech mock for language config

docs/data-model.md

@@ -157,8 +157,8 @@ Single file, validated with `PersistedConfigSchema`.
     providers: Record<providerId, ProviderOverride>
   },
   features: {
-    dictation: { enabled, stt: { provider, model, confidenceThreshold } },
-    voiceMode: { enabled, llm, stt, turnDetection, tts: { provider, model, voice, speakerId, speed } }
+    dictation: { enabled, stt: { provider, model, language, confidenceThreshold } },
+    voiceMode: { enabled, llm, stt: { provider, model, language }, turnDetection, tts: { provider, model, voice, speakerId, speed } }
   },
   log: {
     level, format,

packages/server/src/server/agent/stt-manager.test.ts

@@ -3,6 +3,8 @@ import pino from "pino";
 import { EventEmitter } from "node:events";
 
 import { STTManager } from "./stt-manager.js";
+import { PersistedConfigSchema } from "../persisted-config.js";
+import { resolveSpeechConfig } from "../speech/speech-config-resolver.js";
 import type {
   SpeechToTextProvider,
   StreamingTranscriptionSession,
@@ -16,9 +18,11 @@ type StreamingOnHandler = Parameters<StreamingOn>[1];
 
 class FakeStt implements SpeechToTextProvider {
   public readonly id = "fake";
+  public lastLanguage?: string;
   constructor(private readonly result: TranscriptionResult) {}
 
-  createSession(_params: SessionParams): StreamingTranscriptionSession {
+  createSession(params: SessionParams): StreamingTranscriptionSession {
+    this.lastLanguage = params.language;
     const emitter = new EventEmitter();
     const result = this.result;
     let segmentId = "seg-1";
@@ -92,6 +96,116 @@ class SequencedFakeStt implements SpeechToTextProvider {
 }
 
 describe("STTManager", () => {
+  function resolveVoiceLanguage(params: { env?: NodeJS.ProcessEnv; persisted?: unknown }): string {
+    const result = resolveSpeechConfig({
+      paseoHome: "/tmp/paseo-home",
+      env: params.env ?? ({} as NodeJS.ProcessEnv),
+      persisted: PersistedConfigSchema.parse(params.persisted ?? {}),
+    });
+    return result.speech.sttLanguages.voice;
+  }
+
+  async function transcribeWithResolvedVoiceLanguage(params: {
+    env?: NodeJS.ProcessEnv;
+    persisted?: unknown;
+  }): Promise<FakeStt> {
+    const fakeStt = new FakeStt({ text: "hi", isLowConfidence: false });
+    const manager = new STTManager("s1", pino({ level: "silent" }), fakeStt, {
+      language: resolveVoiceLanguage(params),
+    });
+    await manager.transcribe(Buffer.alloc(2), "audio/pcm;rate=24000");
+    return fakeStt;
+  }
+
+  it("defaults to English when no voice language config is set", async () => {
+    const fakeStt = await transcribeWithResolvedVoiceLanguage({});
+
+    expect(fakeStt.lastLanguage).toBe("en");
+  });
+
+  it("uses PASEO_VOICE_LANGUAGE over PASEO_DICTATION_LANGUAGE", async () => {
+    const fakeStt = await transcribeWithResolvedVoiceLanguage({
+      env: {
+        PASEO_VOICE_LANGUAGE: "pt",
+        PASEO_DICTATION_LANGUAGE: "es",
+      } as NodeJS.ProcessEnv,
+    });
+
+    expect(fakeStt.lastLanguage).toBe("pt");
+  });
+
+  it("uses PASEO_DICTATION_LANGUAGE when PASEO_VOICE_LANGUAGE is unset", async () => {
+    const fakeStt = await transcribeWithResolvedVoiceLanguage({
+      env: {
+        PASEO_DICTATION_LANGUAGE: "pt",
+      } as NodeJS.ProcessEnv,
+    });
+
+    expect(fakeStt.lastLanguage).toBe("pt");
+  });
+
+  it("treats empty voice language env vars as unset", async () => {
+    const fakeStt = await transcribeWithResolvedVoiceLanguage({
+      env: {
+        PASEO_VOICE_LANGUAGE: "",
+        PASEO_DICTATION_LANGUAGE: "  ",
+      } as NodeJS.ProcessEnv,
+    });
+
+    expect(fakeStt.lastLanguage).toBe("en");
+  });
+
+  it("uses settings voice STT language when no env var is set", async () => {
+    const fakeStt = await transcribeWithResolvedVoiceLanguage({
+      persisted: {
+        features: {
+          voiceMode: {
+            stt: {
+              language: "fr",
+            },
+          },
+        },
+      },
+    });
+
+    expect(fakeStt.lastLanguage).toBe("fr");
+  });
+
+  it("uses env voice language over settings voice STT language", async () => {
+    const fakeStt = await transcribeWithResolvedVoiceLanguage({
+      env: {
+        PASEO_VOICE_LANGUAGE: "pt",
+      } as NodeJS.ProcessEnv,
+      persisted: {
+        features: {
+          voiceMode: {
+            stt: {
+              language: "fr",
+            },
+          },
+        },
+      },
+    });
+
+    expect(fakeStt.lastLanguage).toBe("pt");
+  });
+
+  it("falls back to settings dictation STT language when voice language is unset", async () => {
+    const fakeStt = await transcribeWithResolvedVoiceLanguage({
+      persisted: {
+        features: {
+          dictation: {
+            stt: {
+              language: "es",
+            },
+          },
+        },
+      },
+    });
+
+    expect(fakeStt.lastLanguage).toBe("es");
+  });
+
   it("returns empty text for low-confidence transcriptions", async () => {
     const manager = new STTManager(
       "s1",

packages/server/src/server/agent/stt-manager.ts

@@ -111,6 +111,10 @@ export interface SessionTranscriptionResult extends TranscriptionResult {
   format: string;
 }
 
+export interface STTManagerOptions {
+  language?: string;
+}
+
 /**
  * Per-session STT manager
  * Handles speech-to-text transcription
@@ -119,15 +123,18 @@ export class STTManager {
   private readonly sessionId: string;
   private readonly logger: pino.Logger;
   private readonly resolveStt: () => SpeechToTextProvider | null;
+  private readonly language: string;
 
   constructor(
     sessionId: string,
     logger: pino.Logger,
     stt: Resolvable<SpeechToTextProvider | null>,
+    options?: STTManagerOptions,
   ) {
     this.sessionId = sessionId;
     this.logger = logger.child({ module: "agent", component: "stt-manager", sessionId });
     this.resolveStt = toResolver(stt);
+    this.language = options?.language ?? "en";
   }
 
   public getProvider(): SpeechToTextProvider | null {
@@ -171,7 +178,7 @@ export class STTManager {
 
     const session = stt.createSession({
       logger: this.logger.child({ component: "stt-session" }),
-      language: "en",
+      language: this.language,
     });
 
     const pcmForModel = preparePcmForModel(audio, format, session.requiredSampleRate);

packages/server/src/server/bootstrap.ts

@@ -195,8 +195,14 @@ function summarizeAgentMcpDebugBody(body: unknown): Record<string, unknown> {
 export type PaseoOpenAIConfig = OpenAiSpeechProviderConfig;
 export type PaseoLocalSpeechConfig = LocalSpeechProviderConfig;
 
+export interface PaseoSpeechSttLanguages {
+  dictation: string;
+  voice: string;
+}
+
 export interface PaseoSpeechConfig {
   providers: RequestedSpeechProviders;
+  sttLanguages?: PaseoSpeechSttLanguages;
   local?: PaseoLocalSpeechConfig;
 }
 

packages/server/src/server/dictation/dictation-stream-manager.test.ts

@@ -3,6 +3,8 @@ import { EventEmitter } from "node:events";
 import pino from "pino";
 
 import { DictationStreamManager } from "./dictation-stream-manager.js";
+import { PersistedConfigSchema } from "../persisted-config.js";
+import { resolveSpeechConfig } from "../speech/speech-config-resolver.js";
 import type {
   SpeechToTextProvider,
   StreamingTranscriptionSession,
@@ -51,10 +53,12 @@ class FakeRealtimeSession extends EventEmitter implements StreamingTranscription
 
 class FakeSttProvider implements SpeechToTextProvider {
   public readonly id = "fake";
+  public lastLanguage?: string;
   constructor(private readonly session: FakeRealtimeSession) {}
   createSession(
-    _params: Parameters<SpeechToTextProvider["createSession"]>[0],
+    params: Parameters<SpeechToTextProvider["createSession"]>[0],
   ): StreamingTranscriptionSession {
+    this.lastLanguage = params.language;
     return this.session;
   }
 }
@@ -123,6 +127,97 @@ describe("DictationStreamManager (finish buffer-too-small tolerance)", () => {
 });
 
 describe("DictationStreamManager (provider-agnostic provider)", () => {
+  function resolveDictationLanguage(params: {
+    env?: NodeJS.ProcessEnv;
+    persisted?: unknown;
+  }): string {
+    const result = resolveSpeechConfig({
+      paseoHome: "/tmp/paseo-home",
+      env: params.env ?? ({} as NodeJS.ProcessEnv),
+      persisted: PersistedConfigSchema.parse(params.persisted ?? {}),
+    });
+    return result.speech.sttLanguages.dictation;
+  }
+
+  async function startWithResolvedDictationLanguage(params: {
+    env?: NodeJS.ProcessEnv;
+    persisted?: unknown;
+  }): Promise<FakeSttProvider> {
+    const session = new FakeRealtimeSession();
+    const sttProvider = new FakeSttProvider(session);
+    const manager = new DictationStreamManager({
+      logger: pino({ level: "silent" }),
+      emit: () => {},
+      sessionId: "s1",
+      stt: sttProvider,
+      language: resolveDictationLanguage(params),
+    });
+
+    await manager.handleStart("d-lang", "audio/pcm;rate=24000;bits=16");
+    return sttProvider;
+  }
+
+  it("defaults to English when dictation language config is unset", async () => {
+    const sttProvider = await startWithResolvedDictationLanguage({});
+
+    expect(sttProvider.lastLanguage).toBe("en");
+  });
+
+  it("uses PASEO_DICTATION_LANGUAGE when set", async () => {
+    const sttProvider = await startWithResolvedDictationLanguage({
+      env: {
+        PASEO_DICTATION_LANGUAGE: "pt",
+      } as NodeJS.ProcessEnv,
+    });
+
+    expect(sttProvider.lastLanguage).toBe("pt");
+  });
+
+  it("treats empty PASEO_DICTATION_LANGUAGE as unset", async () => {
+    const sttProvider = await startWithResolvedDictationLanguage({
+      env: {
+        PASEO_DICTATION_LANGUAGE: "  ",
+      } as NodeJS.ProcessEnv,
+    });
+
+    expect(sttProvider.lastLanguage).toBe("en");
+  });
+
+  it("uses settings dictation STT language when env var is unset", async () => {
+    const sttProvider = await startWithResolvedDictationLanguage({
+      persisted: {
+        features: {
+          dictation: {
+            stt: {
+              language: "fr",
+            },
+          },
+        },
+      },
+    });
+
+    expect(sttProvider.lastLanguage).toBe("fr");
+  });
+
+  it("uses env dictation language over settings dictation STT language", async () => {
+    const sttProvider = await startWithResolvedDictationLanguage({
+      env: {
+        PASEO_DICTATION_LANGUAGE: "pt",
+      } as NodeJS.ProcessEnv,
+      persisted: {
+        features: {
+          dictation: {
+            stt: {
+              language: "fr",
+            },
+          },
+        },
+      },
+    });
+
+    expect(sttProvider.lastLanguage).toBe("pt");
+  });
+
   it("does not require OPENAI_API_KEY", async () => {
     const original = process.env.OPENAI_API_KEY;
     delete process.env.OPENAI_API_KEY;

packages/server/src/server/dictation/dictation-stream-manager.ts

@@ -130,6 +130,7 @@ export class DictationStreamManager {
   private readonly emit: (msg: DictationStreamOutboundMessage) => void;
   private readonly sessionId: string;
   private readonly resolveStt: () => SpeechToTextProvider | null;
+  private readonly language: string;
   private readonly finalTimeoutMs: number;
   private readonly autoCommitSeconds: number;
   private readonly streams = new Map<string, DictationStreamState>();
@@ -139,6 +140,7 @@ export class DictationStreamManager {
     emit: (msg: DictationStreamOutboundMessage) => void;
     sessionId: string;
     stt: Resolvable<SpeechToTextProvider | null>;
+    language?: string;
     finalTimeoutMs?: number;
     autoCommitSeconds?: number;
   }) {
@@ -146,6 +148,7 @@ export class DictationStreamManager {
     this.emit = params.emit;
     this.sessionId = params.sessionId;
     this.resolveStt = toResolver(params.stt);
+    this.language = params.language ?? "en";
     this.finalTimeoutMs = params.finalTimeoutMs ?? DEFAULT_DICTATION_FINAL_TIMEOUT_MS;
     this.autoCommitSeconds =
       params.autoCommitSeconds ??
@@ -176,7 +179,7 @@ export class DictationStreamManager {
     try {
       stt = sttProvider.createSession({
         logger: this.logger.child({ dictationId }),
-        language: "en",
+        language: this.language,
         prompt: transcriptionPrompt,
       });
     } catch (error) {

packages/server/src/server/persisted-config.test.ts

@@ -483,6 +483,26 @@ describe("PersistedConfigSchema voice mode config", () => {
 
     expect(parsed.features?.voiceMode?.turnDetection?.provider).toBe("local");
   });
+
+  test("accepts trimmed STT language fields", () => {
+    const parsed = PersistedConfigSchema.parse({
+      features: {
+        dictation: {
+          stt: {
+            language: " fr ",
+          },
+        },
+        voiceMode: {
+          stt: {
+            language: " de ",
+          },
+        },
+      },
+    });
+
+    expect(parsed.features?.dictation?.stt?.language).toBe("fr");
+    expect(parsed.features?.voiceMode?.stt?.language).toBe("de");
+  });
 });
 
 describe.skipIf(process.platform === "win32")("persisted config file permissions", () => {

packages/server/src/server/persisted-config.ts

@@ -86,6 +86,7 @@ const FeatureDictationSchema = z
       .object({
         provider: SpeechProviderIdSchema.optional(),
         model: z.string().min(1).optional(),
+        language: z.string().trim().min(1).optional(),
         confidenceThreshold: z.number().optional(),
       })
       .strict()
@@ -107,6 +108,7 @@ const FeatureVoiceModeSchema = z
       .object({
         provider: SpeechProviderIdSchema.optional(),
         model: z.string().min(1).optional(),
+        language: z.string().trim().min(1).optional(),
       })
       .strict()
       .optional(),

packages/server/src/server/session.ts

@@ -546,6 +546,7 @@ export interface SessionOptions {
   daemonConfigStore: DaemonConfigStore;
   mcpBaseUrl?: string | null;
   stt: Resolvable<SpeechToTextProvider | null>;
+  sttLanguage?: string;
   tts: Resolvable<TextToSpeechProvider | null>;
   terminalManager: TerminalManager | null;
   providerSnapshotManager?: ProviderSnapshotManager;
@@ -572,6 +573,7 @@ export interface SessionOptions {
   dictation?: {
     finalTimeoutMs?: number;
     stt?: Resolvable<SpeechToTextProvider | null>;
+    sttLanguage?: string;
     getSpeechReadiness?: () => SpeechReadinessSnapshot;
   };
   agentProviderRuntimeSettings?: AgentProviderRuntimeSettingsMap;
@@ -783,6 +785,7 @@ export class Session {
   private registerVoiceCallerContext?: (agentId: string, context: VoiceCallerContext) => void;
   private unregisterVoiceCallerContext?: (agentId: string) => void;
   private getSpeechReadiness?: () => SpeechReadinessSnapshot;
+  private readonly sttLanguage: string;
   private readonly agentProviderRuntimeSettings: AgentProviderRuntimeSettingsMap | undefined;
   private readonly providerOverrides: Record<string, ProviderOverride> | undefined;
   private readonly isDev: boolean;
@@ -814,6 +817,7 @@ export class Session {
       daemonConfigStore,
       mcpBaseUrl,
       stt,
+      sttLanguage,
       tts,
       terminalManager,
       providerSnapshotManager,
@@ -875,6 +879,7 @@ export class Session {
     this.getDaemonTcpPort = getDaemonTcpPort ?? null;
     this.getDaemonTcpHost = getDaemonTcpHost ?? null;
     this.resolveScriptHealth = resolveScriptHealth ?? null;
+    this.sttLanguage = sttLanguage ?? "en";
     this.subscribeToOptionalManagers();
     this.bindVoiceBridges({ voice, voiceBridge, dictation });
     this.agentProviderRuntimeSettings = agentProviderRuntimeSettings;
@@ -890,7 +895,7 @@ export class Session {
       buildWorkspaceDescriptor: (input) => this.buildWorkspaceDescriptor(input),
     });
 
-    this.initializePerSessionManagers({ tts, stt, dictation });
+    this.initializePerSessionManagers({ tts, stt, sttLanguage, dictation });
 
     // Initialize agent MCP client asynchronously
     void this.initializeAgentMcp();
@@ -1191,16 +1196,20 @@ export class Session {
   private initializePerSessionManagers(params: {
     tts: SessionOptions["tts"];
     stt: SessionOptions["stt"];
+    sttLanguage: SessionOptions["sttLanguage"];
     dictation: SessionOptions["dictation"];
   }): void {
-    const { tts, stt, dictation } = params;
+    const { tts, stt, sttLanguage, dictation } = params;
     this.ttsManager = new TTSManager(this.sessionId, this.sessionLogger, tts);
-    this.sttManager = new STTManager(this.sessionId, this.sessionLogger, stt);
+    this.sttManager = new STTManager(this.sessionId, this.sessionLogger, stt, {
+      language: sttLanguage,
+    });
     this.dictationStreamManager = new DictationStreamManager({
       logger: this.sessionLogger,
       sessionId: this.sessionId,
       emit: (msg) => this.handleDictationManagerMessage(msg),
       stt: dictation?.stt ?? null,
+      language: dictation?.sttLanguage,
       finalTimeoutMs: dictation?.finalTimeoutMs,
     });
   }
@@ -2765,6 +2774,7 @@ export class Session {
       logger: this.sessionLogger.child({ component: "voice-turn-controller" }),
       turnDetection,
       stt,
+      sttLanguage: this.sttLanguage,
       callbacks: {
         onSpeechStarted: async () => {
           this.sessionLogger.debug("Voice VAD speech_started");

packages/server/src/server/speech/providers/local/config.ts

@@ -29,13 +29,21 @@ export interface LocalSpeechProviderConfig {
 
 export interface ResolvedLocalSpeechConfig {
   local: LocalSpeechProviderConfig | undefined;
+  sttLanguages: LocalSpeechSttLanguageConfig;
 }
 
 export type { LocalSpeechModelId, LocalSttModelId, LocalTtsModelId };
 
 const DEFAULT_LOCAL_MODELS_SUBDIR = path.join("models", "local-speech");
+const DEFAULT_STT_LANGUAGE = "en";
+
+export interface LocalSpeechSttLanguageConfig {
+  dictation: string;
+  voice: string;
+}
 
 const NumberLikeSchema = z.union([z.number(), z.string().trim().min(1)]);
+const LanguageSchema = z.string().trim().min(1).default(DEFAULT_STT_LANGUAGE);
 
 const OptionalFiniteNumberSchema = NumberLikeSchema.pipe(z.coerce.number().finite()).optional();
 
@@ -47,6 +55,8 @@ const LocalSpeechResolutionSchema = z.object({
   dictationLocalSttModel: LocalSttModelIdSchema.default(DEFAULT_LOCAL_STT_MODEL),
   voiceLocalSttModel: LocalSttModelIdSchema.default(DEFAULT_LOCAL_STT_MODEL),
   voiceLocalTtsModel: LocalTtsModelIdSchema.default(DEFAULT_LOCAL_TTS_MODEL),
+  dictationLanguage: LanguageSchema,
+  voiceLanguage: LanguageSchema,
   voiceLocalTtsSpeakerId: OptionalIntegerSchema,
   voiceLocalTtsSpeed: OptionalFiniteNumberSchema,
 });
@@ -90,6 +100,37 @@ function firstDefinedValue<T>(values: Array<T | null | undefined>): T | undefine
   return undefined;
 }
 
+function firstNonEmptyString(values: Array<string | null | undefined>): string | undefined {
+  for (const value of values) {
+    const trimmed = value?.trim();
+    if (trimmed) {
+      return trimmed;
+    }
+  }
+  return undefined;
+}
+
+function buildLocalSpeechLanguageResolutionInput(params: {
+  env: NodeJS.ProcessEnv;
+  persisted: PersistedConfig;
+}): Record<string, unknown> {
+  const { env, persisted } = params;
+  return {
+    dictationLanguage: firstNonEmptyString([
+      env.PASEO_DICTATION_LANGUAGE,
+      persisted.features?.dictation?.stt?.language,
+      DEFAULT_STT_LANGUAGE,
+    ]),
+    voiceLanguage: firstNonEmptyString([
+      env.PASEO_VOICE_LANGUAGE,
+      env.PASEO_DICTATION_LANGUAGE,
+      persisted.features?.voiceMode?.stt?.language,
+      persisted.features?.dictation?.stt?.language,
+      DEFAULT_STT_LANGUAGE,
+    ]),
+  };
+}
+
 function buildLocalSpeechResolutionInput(params: {
   paseoHome: string;
   env: NodeJS.ProcessEnv;
@@ -132,6 +173,7 @@ function buildLocalSpeechResolutionInput(params: {
       ),
       DEFAULT_LOCAL_TTS_MODEL,
     ]),
+    ...buildLocalSpeechLanguageResolutionInput({ env, persisted }),
     voiceLocalTtsSpeakerId: firstDefinedValue<string | number>([
       env.PASEO_VOICE_LOCAL_TTS_SPEAKER_ID,
       persisted.features?.voiceMode?.tts?.speakerId,
@@ -159,6 +201,10 @@ export function resolveLocalSpeechConfig(params: {
     (parsed.voiceLocalTtsModel === "kokoro-en-v0_19" ? 0 : undefined);
 
   return {
+    sttLanguages: {
+      dictation: parsed.dictationLanguage,
+      voice: parsed.voiceLanguage,
+    },
     local: parsed.includeProviderConfig
       ? {
           modelsDir: parsed.modelsDir,

packages/server/src/server/speech/speech-config-resolver.test.ts

@@ -51,6 +51,10 @@ describe("resolveSpeechConfig", () => {
     expect(result.speech.local?.models.voiceStt).toBe("parakeet-tdt-0.6b-v2-int8");
     expect(result.speech.local?.models.voiceTts).toBe("kokoro-en-v0_19");
     expect(result.speech.local?.models.voiceTtsSpeakerId).toBe(0);
+    expect(result.speech.sttLanguages).toEqual({
+      dictation: "en",
+      voice: "en",
+    });
   });
 
   test("resolves feature-scoped local model env vars", () => {
@@ -71,6 +75,8 @@ describe("resolveSpeechConfig", () => {
       PASEO_VOICE_LOCAL_TTS_MODEL: "kitten",
       PASEO_VOICE_LOCAL_TTS_SPEAKER_ID: "5",
       PASEO_VOICE_LOCAL_TTS_SPEED: "1.35",
+      PASEO_DICTATION_LANGUAGE: "es",
+      PASEO_VOICE_LANGUAGE: "pt",
       PASEO_LOCAL_MODELS_DIR: "/tmp/models",
       OPENAI_API_KEY: "env-key",
       PASEO_VOICE_STT_PROVIDER: "openai",
@@ -119,10 +125,45 @@ describe("resolveSpeechConfig", () => {
     expect(result.speech.local?.models.voiceTts).toBe("kitten-nano-en-v0_1-fp16");
     expect(result.speech.local?.models.voiceTtsSpeakerId).toBe(5);
     expect(result.speech.local?.models.voiceTtsSpeed).toBe(1.35);
+    expect(result.speech.sttLanguages).toEqual({
+      dictation: "es",
+      voice: "pt",
+    });
     expect(result.openai?.apiKey).toBe("env-key");
     expect(result.openai?.stt?.model).toBe("gpt-4o-transcribe");
   });
 
+  test("resolves STT language from env, settings, and voice-to-dictation fallback", () => {
+    const persisted = PersistedConfigSchema.parse({
+      features: {
+        dictation: {
+          stt: {
+            language: "fr",
+          },
+        },
+        voiceMode: {
+          stt: {
+            language: "de",
+          },
+        },
+      },
+    });
+
+    const result = resolveSpeechConfig({
+      paseoHome: "/tmp/paseo-home",
+      env: {
+        PASEO_DICTATION_LANGUAGE: "es",
+        PASEO_VOICE_LANGUAGE: "  ",
+      } as NodeJS.ProcessEnv,
+      persisted,
+    });
+
+    expect(result.speech.sttLanguages).toEqual({
+      dictation: "es",
+      voice: "es",
+    });
+  });
+
   test("ignores deprecated shared local model env vars", () => {
     const persisted = PersistedConfigSchema.parse({});
     const env = {

packages/server/src/server/speech/speech-config-resolver.ts

@@ -173,6 +173,7 @@ export function resolveSpeechConfig(params: {
     openai,
     speech: {
       providers,
+      sttLanguages: local.sttLanguages,
       ...(local.local ? { local: local.local } : {}),
     },
   };

packages/server/src/server/speech/speech-runtime.test.ts

@@ -67,7 +67,13 @@ function createStubTurnDetection(id: string): TurnDetectionProvider {
 }
 
 function createSpeechConfig(providers: PaseoSpeechConfig["providers"]): PaseoSpeechConfig {
-  return { providers };
+  return {
+    providers,
+    sttLanguages: {
+      dictation: "en",
+      voice: "en",
+    },
+  };
 }
 
 describe("createSpeechService readiness", () => {

packages/server/src/server/speech/speech-runtime.ts

@@ -342,9 +342,11 @@ function resolveEffectiveProviderIds(params: {
 
 export interface SpeechService {
   resolveStt: () => SpeechToTextProvider | null;
+  resolveSttLanguage: () => string;
   resolveTts: () => TextToSpeechProvider | null;
   resolveTurnDetection: () => TurnDetectionProvider | null;
   resolveDictationStt: () => SpeechToTextProvider | null;
+  resolveDictationSttLanguage: () => string;
   getReadiness: () => SpeechReadinessSnapshot;
   onReadinessChange: (listener: (snapshot: SpeechReadinessSnapshot) => void) => () => void;
   start: () => void;
@@ -709,8 +711,10 @@ export function createSpeechService(params: {
   return {
     resolveTurnDetection: () => turnDetectionService,
     resolveStt: () => sttService,
+    resolveSttLanguage: () => speechConfig?.sttLanguages?.voice ?? "en",
     resolveTts: () => ttsService,
     resolveDictationStt: () => dictationSttService,
+    resolveDictationSttLanguage: () => speechConfig?.sttLanguages?.dictation ?? "en",
     getReadiness: () => lastPublishedReadinessSnapshot ?? computeReadinessSnapshot(),
     onReadinessChange: subscribeSpeechReadiness,
     start,

packages/server/src/server/voice/voice-turn-controller.test.ts

@@ -81,10 +81,14 @@ function createFakeTurnDetectionProvider(session: FakeTurnDetectionSession): Tur
   };
 }
 
-function createFakeSttProvider(sessions: FakeSttSession[]): SpeechToTextProvider {
+function createFakeSttProvider(
+  sessions: FakeSttSession[],
+  captureLanguage?: (language: string | undefined) => void,
+): SpeechToTextProvider {
   return {
     id: "local",
-    createSession() {
+    createSession(params) {
+      captureLanguage?.(params.language);
       const session = new FakeSttSession();
       sessions.push(session);
       return session;
@@ -98,10 +102,13 @@ async function settleSerialQueue(): Promise<void> {
   await Promise.resolve();
 }
 
-function createControllerHarness() {
+function createControllerHarness(options?: { sttLanguage?: string }) {
   const detector = new FakeTurnDetectionSession();
   const sttSessions: FakeSttSession[] = [];
-  const stt = createFakeSttProvider(sttSessions);
+  let lastSttLanguage: string | undefined;
+  const stt = createFakeSttProvider(sttSessions, (language) => {
+    lastSttLanguage = language;
+  });
   const onSpeechStarted = vi.fn(async () => {});
   const onSpeechStopped = vi.fn(async () => {});
   const onPartialTranscript = vi.fn(
@@ -123,6 +130,7 @@ function createControllerHarness() {
     logger: pino({ level: "silent" }),
     turnDetection: createFakeTurnDetectionProvider(detector),
     stt,
+    sttLanguage: options?.sttLanguage,
     callbacks: {
       onSpeechStarted,
       onSpeechStopped,
@@ -136,6 +144,7 @@ function createControllerHarness() {
     controller,
     detector,
     sttSessions,
+    getLastSttLanguage: () => lastSttLanguage,
     onSpeechStarted,
     onSpeechStopped,
     onPartialTranscript,
@@ -145,6 +154,16 @@ function createControllerHarness() {
 }
 
 describe("voice turn controller", () => {
+  it("passes configured language to streaming STT", async () => {
+    const harness = createControllerHarness({ sttLanguage: "pt" });
+
+    await harness.controller.start();
+    harness.detector.emit("speech_started");
+    await settleSerialQueue();
+
+    expect(harness.getLastSttLanguage()).toBe("pt");
+  });
+
   it("forwards audio to the detector and streaming STT without submitting buffered utterances", async () => {
     const harness = createControllerHarness();
 

packages/server/src/server/voice/voice-turn-controller.ts

@@ -94,6 +94,7 @@ export function createVoiceTurnController(params: {
   logger: Logger;
   turnDetection: TurnDetectionProvider;
   stt: SpeechToTextProvider;
+  sttLanguage?: string;
   callbacks: VoiceTurnControllerCallbacks;
 }): VoiceTurnController {
   const detector = params.turnDetection.createSession({
@@ -319,7 +320,7 @@ export function createVoiceTurnController(params: {
   function createSttSession(): StreamingTranscriptionSession {
     const session = params.stt.createSession({
       logger: params.logger.child({ component: "stt" }),
-      language: "en",
+      language: params.sttLanguage ?? "en",
     });
     session.on("transcript", handleSttTranscript);
     session.on("committed", ({ segmentId }) => {

packages/server/src/server/websocket-server.relay-reconnect.test.ts

@@ -215,8 +215,17 @@ function createServer(options?: { speechReadiness?: SpeechReadinessSnapshot | nu
     undefined,
     speechReadiness
       ? {
+          resolveStt: () => null,
+          resolveSttLanguage: () => "en",
+          resolveTts: () => null,
+          resolveTurnDetection: () => null,
+          resolveDictationStt: () => null,
+          resolveDictationSttLanguage: () => "en",
           getReadiness: () => speechReadiness,
           onReadinessChange: vi.fn(() => () => {}),
+          start: vi.fn(),
+          stop: vi.fn(),
+          ready: Promise.resolve(),
         }
       : undefined,
     undefined,

packages/server/src/server/websocket-server.ts

@@ -878,6 +878,7 @@ export class VoiceAssistantWebSocketServer {
       daemonConfigStore: this.daemonConfigStore,
       mcpBaseUrl: this.mcpBaseUrl,
       stt: () => this.speech?.resolveStt() ?? null,
+      sttLanguage: this.speech?.resolveSttLanguage() ?? "en",
       tts: () => this.speech?.resolveTts() ?? null,
       terminalManager: this.terminalManager,
       providerSnapshotManager: this.providerSnapshotManager,
@@ -910,6 +911,7 @@ export class VoiceAssistantWebSocketServer {
           ? {
               finalTimeoutMs: this.dictation?.finalTimeoutMs,
               stt: () => this.speech?.resolveDictationStt() ?? null,
+              sttLanguage: this.speech?.resolveDictationSttLanguage() ?? "en",
               getSpeechReadiness: () => this.speech!.getReadiness(),
             }
           : undefined,

public-docs/configuration.md

@@ -161,6 +161,7 @@ In the mobile app, enter the password in the direct connection setup screen.
 - `PASEO_LOCAL_MODELS_DIR`, control local model directory
 - `PASEO_DICTATION_LOCAL_STT_MODEL`, override local dictation STT model
 - `PASEO_VOICE_LOCAL_STT_MODEL`, `PASEO_VOICE_LOCAL_TTS_MODEL`, override local voice STT/TTS models
+- `PASEO_DICTATION_LANGUAGE`, `PASEO_VOICE_LANGUAGE`, override dictation and voice STT language
 - `PASEO_VOICE_LOCAL_TTS_SPEAKER_ID`, `PASEO_VOICE_LOCAL_TTS_SPEED`, optional local voice TTS tuning
 
 ## Schema

public-docs/voice.md

@@ -24,7 +24,7 @@ This keeps credentials and execution in your environment and avoids introducing
 
 ## Local Speech
 
-Local speech defaults to model IDs `parakeet-tdt-0.6b-v3-int8` (STT) and `kokoro-en-v0_19` (TTS, speaker 0 / voice 00).
+Local speech defaults to model IDs `parakeet-tdt-0.6b-v3-int8` (STT) and `kokoro-en-v0_19` (TTS, speaker 0 / voice 00). STT language defaults to `en`.
 
 Missing models are downloaded at daemon startup into `$PASEO_HOME/models/local-speech`. Downloads happen only for missing files.
 
@@ -32,10 +32,12 @@ Missing models are downloaded at daemon startup into `$PASEO_HOME/models/local-s
 {
   "version": 1,
   "features": {
-    "dictation": { "stt": { "provider": "local", "model": "parakeet-tdt-0.6b-v3-int8" } },
+    "dictation": {
+      "stt": { "provider": "local", "model": "parakeet-tdt-0.6b-v3-int8", "language": "en" }
+    },
     "voiceMode": {
       "llm": { "provider": "claude", "model": "haiku" },
-      "stt": { "provider": "local", "model": "parakeet-tdt-0.6b-v3-int8" },
+      "stt": { "provider": "local", "model": "parakeet-tdt-0.6b-v3-int8", "language": "en" },
       "tts": { "provider": "local", "model": "kokoro-en-v0_19", "speakerId": 0 }
     }
   },
@@ -47,6 +49,8 @@ Missing models are downloaded at daemon startup into `$PASEO_HOME/models/local-s
 }
 ```
 
+Set `features.dictation.stt.language` for dictation and `features.voiceMode.stt.language` for realtime voice. If voice language is omitted, Paseo uses the dictation language before falling back to `en`.
+
 ## OpenAI Speech Option
 
 You can switch dictation, voice STT, and voice TTS to OpenAI by setting provider fields to `openai` and providing `OPENAI_API_KEY`.
@@ -74,6 +78,8 @@ You can switch dictation, voice STT, and voice TTS to OpenAI by setting provider
 - `PASEO_LOCAL_MODELS_DIR`, local model storage directory
 - `PASEO_DICTATION_LOCAL_STT_MODEL`, local dictation STT model ID
 - `PASEO_VOICE_LOCAL_STT_MODEL`, `PASEO_VOICE_LOCAL_TTS_MODEL`, local voice STT/TTS model IDs
+- `PASEO_DICTATION_LANGUAGE`, dictation STT language
+- `PASEO_VOICE_LANGUAGE`, realtime voice STT language; falls back to `PASEO_DICTATION_LANGUAGE` when unset
 - `PASEO_VOICE_LOCAL_TTS_SPEAKER_ID`, `PASEO_VOICE_LOCAL_TTS_SPEED`, optional local voice TTS tuning
 
 ## Operational Notes