Include examples in type checking

Remove `examples/` from the `pyrightconfig.json` ignore list and fix
the resulting type errors across all example files. Common fixes:

- Required API keys: `os.getenv("X")` -> `os.environ["X"]` so the
  return type is `str` rather than `str | None`, and misconfiguration
  fails fast.
- Narrow `LLMContextMessage` union members with `isinstance(..., dict)`
  before dict-style access.
- `assert isinstance(params.llm, ...)` before calling service-specific
  methods that aren't on the base `LLMService`.
- Guard optional frame fields (e.g. `LLMSearchResponseFrame.search_result`)
  before use.

examples/transcription/transcription-assemblyai.py

@@ -48,7 +48,7 @@ async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
     stt = AssemblyAISTTService(
-        api_key=os.getenv("ASSEMBLYAI_API_KEY"),
+        api_key=os.environ["ASSEMBLYAI_API_KEY"],
         settings=AssemblyAISTTService.Settings(
             model="u3-rt-pro",
         ),

examples/transcription/transcription-azure.py

@@ -54,7 +54,7 @@ async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
     stt = AzureSTTService(
-        api_key=os.getenv("AZURE_SPEECH_API_KEY"),
+        api_key=os.environ["AZURE_SPEECH_API_KEY"],
         region=os.getenv("AZURE_SPEECH_REGION"),
     )
 

examples/transcription/transcription-cartesia.py

@@ -47,7 +47,7 @@ transport_params = {
 async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
-    stt = CartesiaSTTService(api_key=os.getenv("CARTESIA_API_KEY"))
+    stt = CartesiaSTTService(api_key=os.environ["CARTESIA_API_KEY"])
 
     tl = TranscriptionLogger()
 

examples/transcription/transcription-deepgram.py

@@ -48,7 +48,7 @@ async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
     stt = DeepgramSTTService(
-        api_key=os.getenv("DEEPGRAM_API_KEY"),
+        api_key=os.environ["DEEPGRAM_API_KEY"],
         settings=DeepgramSTTService.Settings(
             language=Language.EN,
         ),

examples/transcription/transcription-elevenlabs.py

@@ -49,7 +49,7 @@ transport_params = {
 async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
-    stt = ElevenLabsRealtimeSTTService(api_key=os.getenv("ELEVENLABS_API_KEY"))
+    stt = ElevenLabsRealtimeSTTService(api_key=os.environ["ELEVENLABS_API_KEY"])
 
     tl = TranscriptionLogger()
     vad_processor = VADProcessor(vad_analyzer=SileroVADAnalyzer())

examples/transcription/transcription-gladia-translation.py

@@ -55,9 +55,12 @@ transport_params = {
 async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
+    region = os.getenv("GLADIA_REGION", "us-west")
+    assert region in ("us-west", "eu-west"), f"Invalid GLADIA_REGION: {region}"
+
     stt = GladiaSTTService(
-        api_key=os.getenv("GLADIA_API_KEY"),
-        region=os.getenv("GLADIA_REGION"),
+        api_key=os.environ["GLADIA_API_KEY"],
+        region=region,
         settings=GladiaSTTService.Settings(
             language_config=LanguageConfig(
                 languages=[Language.EN],

examples/transcription/transcription-gladia.py

@@ -47,9 +47,12 @@ transport_params = {
 async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
+    region = os.getenv("GLADIA_REGION", "us-west")
+    assert region in ("us-west", "eu-west"), f"Invalid GLADIA_REGION: {region}"
+
     stt = GladiaSTTService(
-        api_key=os.getenv("GLADIA_API_KEY"),
-        region=os.getenv("GLADIA_REGION"),
+        api_key=os.environ["GLADIA_API_KEY"],
+        region=region,
         # settings=GladiaSTTSettings(
         #     language_config=LanguageConfig(
         #         languages=[Language.FR],

examples/transcription/transcription-google-llm.py

@@ -289,7 +289,7 @@ async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
     tts = CartesiaTTSService(
-        api_key=os.getenv("CARTESIA_API_KEY"),
+        api_key=os.environ["CARTESIA_API_KEY"],
         settings=CartesiaTTSService.Settings(
             voice="71a7ad14-091c-4e8e-a314-022ece01c121",  # British Reading Lady
         ),
@@ -301,7 +301,7 @@ async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
             model="gemini-2.5-flash",
             system_instruction=conversation_system_message,
         ),
-        api_key=os.getenv("GOOGLE_API_KEY"),
+        api_key=os.environ["GOOGLE_API_KEY"],
         # we can give the GoogleLLMService a system instruction to use directly
         # in the GenerativeModel constructor. Let's do that rather than put
         # our system message in the messages list.
@@ -313,7 +313,7 @@ async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
             model="gemini-2.5-flash",
             system_instruction=transcriber_system_message,
         ),
-        api_key=os.getenv("GOOGLE_API_KEY"),
+        api_key=os.environ["GOOGLE_API_KEY"],
     )
 
     messages = [

examples/transcription/transcription-gradium.py

@@ -50,7 +50,7 @@ async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
     stt = GradiumSTTService(
-        api_key=os.getenv("GRADIUM_API_KEY"),
+        api_key=os.environ["GRADIUM_API_KEY"],
         api_endpoint_base_url="wss://us.api.gradium.ai/api/speech/asr",
         settings=GradiumSTTService.Settings(
             language=Language.EN,

examples/transcription/transcription-mistral.py

@@ -54,7 +54,7 @@ async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
     stt = MistralSTTService(
-        api_key=os.getenv("MISTRAL_API_KEY"),
+        api_key=os.environ["MISTRAL_API_KEY"],
     )
 
     tl = TranscriptionLogger()

examples/transcription/transcription-openai.py

@@ -50,7 +50,7 @@ async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
     stt = OpenAIRealtimeSTTService(
-        api_key=os.getenv("OPENAI_API_KEY"),
+        api_key=os.environ["OPENAI_API_KEY"],
         settings=OpenAIRealtimeSTTService.Settings(
             model="gpt-4o-transcribe",
             prompt="Expect words related to dogs, such as breed names.",

examples/transcription/transcription-soniox.py

@@ -54,7 +54,7 @@ async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
     stt = SonioxSTTService(
-        api_key=os.getenv("SONIOX_API_KEY"),
+        api_key=os.environ["SONIOX_API_KEY"],
     )
 
     tl = TranscriptionLogger()

examples/transcription/transcription-speechmatics.py

@@ -64,7 +64,7 @@ async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
     stt = SpeechmaticsSTTService(
-        api_key=os.getenv("SPEECHMATICS_API_KEY"),
+        api_key=os.environ["SPEECHMATICS_API_KEY"],
         settings=SpeechmaticsSTTService.Settings(
             language=Language.EN,
             speaker_active_format="<{speaker_id}>{text}</{speaker_id}>",