From b1dafc3188bc09a87de0aaa0cc286b95b27135fb Mon Sep 17 00:00:00 2001
From: sam <jamesagart@gmail.com>
Date: Tue, 11 Aug 2026 15:54:40 -0700
Subject: [PATCH 1/2] docs: add a Gandr custom-voice integration guide

---
 fern/customization/custom-voices/gandr.mdx | 49 ++++++++++++++++++++++
 fern/docs.yml                              |  2 +
 2 files changed, 51 insertions(+)
 create mode 100644 fern/customization/custom-voices/gandr.mdx

diff --git a/fern/customization/custom-voices/gandr.mdx b/fern/customization/custom-voices/gandr.mdx
new file mode 100644
index 000000000..50d454e91
--- /dev/null
+++ b/fern/customization/custom-voices/gandr.mdx
@@ -0,0 +1,49 @@
+---
+title: Gandr
+subtitle: Use Gandr voices in Vapi through the custom-voice provider
+description: Wire Gandr, a text to speech API for voice agents, into Vapi with the custom-voice provider and Custom Credentials.
+slug: customization/custom-voices/gandr
+---
+
+Gandr is a text to speech API built for voice agents. It reads numbers, dates, order IDs and addresses correctly, one engine speaks 23 languages with six voices, and every render carries an inaudible watermark. Audio streams back as it is generated.
+
+Gandr's `/v1/vapi` endpoint implements the custom-voice contract described in the [Custom TTS guide](/customization/custom-voices/custom-tts): it reads the nested `message` envelope, honours the requested `sampleRate` (8000, 16000, 22050, 24000 or 44100), and returns raw 16-bit little-endian mono PCM.
+
+<Note>A Gandr account and API key are required. The free key starts at 100,000 tokens, no card.</Note>
+
+<Steps>
+  <Step title="Create a Gandr key">
+    Sign up at [gandr.ai](https://gandr.ai) and copy your API key.
+  </Step>
+  <Step title="Store the key in a Custom Credential">
+    In the [Vapi Dashboard](https://dashboard.vapi.ai), create a **Custom Credential** holding your Gandr key, following [server authentication](/server-url/server-authentication), so the key never travels in the assistant config.
+  </Step>
+  <Step title="Add Gandr as the voice provider">
+    In the assistant config, set the voice provider to `custom-voice` and point it at Gandr:
+
+    ```json
+    {
+      "voice": {
+        "provider": "custom-voice",
+        "server": {
+          "url": "https://tts.gandr.ai/v1/vapi",
+          "credentialId": "<your-custom-credential-id>",
+          "timeoutSeconds": 10
+        }
+      }
+    }
+    ```
+  </Step>
+  <Step title="Pick a voice and language">
+    Gandr's stock voices are `gandr-ava`, `gandr-dane`, `gandr-jenny`, `gandr-leo`, `gandr-lewis` and `gandr-mia`. The default is an English female voice. Any of the 23 languages can be set per request, independent of the voice.
+  </Step>
+  <Step title="Test the call">
+    Run a test call in the dashboard. If you hear audio, you are done. If the call times out, check that the Gandr key in the Custom Credential is active and that `https://tts.gandr.ai/v1/vapi` answers.
+  </Step>
+</Steps>
+
+## Pricing
+
+Gandr is $10 per million tokens, or $150 a month for an unmetered stream (one connection held open around the clock). The free key carries 100,000 tokens with no card.
+
+Full API reference: [gandr.ai/docs](https://gandr.ai/docs).
diff --git a/fern/docs.yml b/fern/docs.yml
index 233656a44..af8561e96 100644
--- a/fern/docs.yml
+++ b/fern/docs.yml
@@ -277,6 +277,8 @@ navigation:
                 path: customization/custom-voices/playht.mdx
               - page: Cartesia
                 path: customization/custom-voices/cartesia.mdx
+              - page: Gandr
+                path: customization/custom-voices/gandr.mdx
           - page: Custom transcriber
             path: customization/custom-transcriber.mdx
             icon: fa-light fa-microphone

From 6149f59327291c2ef3b326a6a95a990cc453f5c5 Mon Sep 17 00:00:00 2001
From: Sam Alghaithi <alghaihtia@gmail.com>
Date: Wed, 12 Aug 2026 19:40:27 -0700
Subject: [PATCH 2/2] Fix free tier to 50,000 tokens in the gandr.mdx
 custom-voice doc

---
 fern/customization/custom-voices/gandr.mdx | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fern/customization/custom-voices/gandr.mdx b/fern/customization/custom-voices/gandr.mdx
index 50d454e91..ac944f641 100644
--- a/fern/customization/custom-voices/gandr.mdx
+++ b/fern/customization/custom-voices/gandr.mdx
@@ -9,7 +9,7 @@ Gandr is a text to speech API built for voice agents. It reads numbers, dates, o
 
 Gandr's `/v1/vapi` endpoint implements the custom-voice contract described in the [Custom TTS guide](/customization/custom-voices/custom-tts): it reads the nested `message` envelope, honours the requested `sampleRate` (8000, 16000, 22050, 24000 or 44100), and returns raw 16-bit little-endian mono PCM.
 
-<Note>A Gandr account and API key are required. The free key starts at 100,000 tokens, no card.</Note>
+<Note>A Gandr account and API key are required. The free key starts at 50,000 tokens.</Note>
 
 <Steps>
   <Step title="Create a Gandr key">
@@ -44,6 +44,6 @@ Gandr's `/v1/vapi` endpoint implements the custom-voice contract described in th
 
 ## Pricing
 
-Gandr is $10 per million tokens, or $150 a month for an unmetered stream (one connection held open around the clock). The free key carries 100,000 tokens with no card.
+Gandr is $10 per million tokens, or $150 a month for an unmetered stream (one connection held open around the clock). The free key carries 50,000 tokens.
 
 Full API reference: [gandr.ai/docs](https://gandr.ai/docs).