feat: fall back to WHISPER_API_KEY for whisper transcription

When neither WDOC_WHISPER_API_KEY nor OPENAI_API_KEY is set, resolve the
whisper API key from a WHISPER_API_KEY environment variable if present.
Resolution order: WDOC_WHISPER_API_KEY > OPENAI_API_KEY > WHISPER_API_KEY.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: thiswillbeyourgithub

wdoc-skill/REFERENCE.md

@@ -327,7 +327,7 @@ These load multiple documents and can combine different sources:
 | Variable | Default | Description |
 |----------|---------|-------------|
 | `WDOC_WHISPER_ENDPOINT` | `""` | Custom Whisper API endpoint |
-| `WDOC_WHISPER_API_KEY` | `""` | Custom Whisper API key |
+| `WDOC_WHISPER_API_KEY` | `""` | Custom Whisper API key. When empty, falls back to `OPENAI_API_KEY`, then `WHISPER_API_KEY` |
 | `WDOC_WHISPER_MODEL` | `whisper-1` | Whisper model name |
 | `WDOC_WHISPER_PARALLEL_SPLITS` | `True` | Parallelize split audio transcription |
 

wdoc/docs/help.md

@@ -947,7 +947,8 @@
 * `WDOC_WHISPER_API_KEY`, default: `""`
     * If provided, sets a custom API key for Whisper transcription services. This is useful when using alternative 
     Whisper-compatible services that require their own authentication.
-    * When empty, uses the default OPENAI_API_KEY environment variable.
+    * When empty, falls back to the `OPENAI_API_KEY` environment variable, and if that is also unset, to the 
+    `WHISPER_API_KEY` environment variable. The resolution order is `WDOC_WHISPER_API_KEY` > `OPENAI_API_KEY` > `WHISPER_API_KEY`.
 
 * `WDOC_WHISPER_MODEL`, default: `"whisper-1"`
     * Specifies which Whisper model to use for audio transcription. This can be any model supported by your Whisper endpoint.

wdoc/utils/loaders/shared_audio.py

@@ -210,13 +210,30 @@ def transcribe_audio_whisper(
         )
     else:
         assert (
-            "OPENAI_API_KEY" in os.environ
-            and not os.environ["OPENAI_API_KEY"]
-            == "REDACTED_BECAUSE_WDOC_IN_PRIVATE_MODE"
-        ) or (
-            env.WDOC_WHISPER_API_KEY
-            and not env.WDOC_WHISPER_API_KEY == "REDACTED_BECAUSE_WDOC_IN_PRIVATE_MODE"
-        ), "No environment variable OPENAI_API_KEY nor WDOC_WHISPER_API_KEY found"
+            (
+                "OPENAI_API_KEY" in os.environ
+                and not os.environ["OPENAI_API_KEY"]
+                == "REDACTED_BECAUSE_WDOC_IN_PRIVATE_MODE"
+            )
+            or (
+                env.WDOC_WHISPER_API_KEY
+                and not env.WDOC_WHISPER_API_KEY
+                == "REDACTED_BECAUSE_WDOC_IN_PRIVATE_MODE"
+            )
+            or (
+                os.environ.get("WHISPER_API_KEY")
+                and not os.environ["WHISPER_API_KEY"]
+                == "REDACTED_BECAUSE_WDOC_IN_PRIVATE_MODE"
+            )
+        ), (
+            "No environment variable OPENAI_API_KEY, WDOC_WHISPER_API_KEY nor WHISPER_API_KEY found"
+        )
+
+    # Resolve the whisper API key. WDOC_WHISPER_API_KEY takes precedence; if it
+    # is unset and OPENAI_API_KEY is also unset, fall back to WHISPER_API_KEY.
+    whisper_api_key = env.WDOC_WHISPER_API_KEY
+    if not whisper_api_key and not os.environ.get("OPENAI_API_KEY"):
+        whisper_api_key = os.environ.get("WHISPER_API_KEY", "")
 
     try:
         t1 = time.time()
@@ -238,8 +255,8 @@ def transcribe_audio_whisper(
                     f"Using custom whisper endpoint: {env.WDOC_WHISPER_ENDPOINT}"
                 )
 
-            if env.WDOC_WHISPER_API_KEY:
-                transcription_kwargs["api_key"] = env.WDOC_WHISPER_API_KEY
+            if whisper_api_key:
+                transcription_kwargs["api_key"] = whisper_api_key
                 logger.debug("Using custom whisper API key")
 
             try:
@@ -270,8 +287,8 @@ def transcribe_audio_whisper(
                     data["language"] = language
 
                 headers = {}
-                if env.WDOC_WHISPER_API_KEY:
-                    headers["Authorization"] = f"Bearer {env.WDOC_WHISPER_API_KEY}"
+                if whisper_api_key:
+                    headers["Authorization"] = f"Bearer {whisper_api_key}"
 
                 # Make the request
                 endpoint_url = (