diff --git a/swagger/docs.go b/swagger/docs.go
index 02730a48d..83314766e 100644
--- a/swagger/docs.go
+++ b/swagger/docs.go
@@ -6897,6 +6897,10 @@ const docTemplate = `{
                     "description": "(optional) desired output sample rate",
                     "type": "integer"
                 },
+                "speed": {
+                    "description": "Speed is the OpenAI ` + "`" + `speed` + "`" + ` field (0.25-4.0). It is a pointer so an\nexplicit ` + "`" + `\"speed\": 0` + "`" + ` (invalid, rejected with 400) is distinguishable\nfrom an omitted field (left at the backend default). It is normalised\ninto Params[\"speed\"] so it reaches the backend over the same channel as\nthe other per-request generation parameters.",
+                    "type": "number"
+                },
                 "stream": {
                     "description": "(optional) enable streaming TTS",
                     "type": "boolean"
diff --git a/swagger/swagger.json b/swagger/swagger.json
index abc81df78..db9bee118 100644
--- a/swagger/swagger.json
+++ b/swagger/swagger.json
@@ -6894,6 +6894,10 @@
                     "description": "(optional) desired output sample rate",
                     "type": "integer"
                 },
+                "speed": {
+                    "description": "Speed is the OpenAI `speed` field (0.25-4.0). It is a pointer so an\nexplicit `\"speed\": 0` (invalid, rejected with 400) is distinguishable\nfrom an omitted field (left at the backend default). It is normalised\ninto Params[\"speed\"] so it reaches the backend over the same channel as\nthe other per-request generation parameters.",
+                    "type": "number"
+                },
                 "stream": {
                     "description": "(optional) enable streaming TTS",
                     "type": "boolean"
diff --git a/swagger/swagger.yaml b/swagger/swagger.yaml
index afcd67fdc..2b92f5233 100644
--- a/swagger/swagger.yaml
+++ b/swagger/swagger.yaml
@@ -2336,6 +2336,14 @@ definitions:
       sample_rate:
         description: (optional) desired output sample rate
         type: integer
+      speed:
+        description: |-
+          Speed is the OpenAI `speed` field (0.25-4.0). It is a pointer so an
+          explicit `"speed": 0` (invalid, rejected with 400) is distinguishable
+          from an omitted field (left at the backend default). It is normalised
+          into Params["speed"] so it reaches the backend over the same channel as
+          the other per-request generation parameters.
+        type: number
       stream:
         description: (optional) enable streaming TTS
         type: boolean