diff --git a/crates/api_clients/artcraft/artcraft_api_defs/src/omni_gen/cost_response/omni_gen_video_cost_response.rs b/crates/api_clients/artcraft/artcraft_api_defs/src/omni_gen/cost_response/omni_gen_video_cost_response.rs
index 3885709abf..2bd98df28e 100644
--- a/crates/api_clients/artcraft/artcraft_api_defs/src/omni_gen/cost_response/omni_gen_video_cost_response.rs
+++ b/crates/api_clients/artcraft/artcraft_api_defs/src/omni_gen/cost_response/omni_gen_video_cost_response.rs
@@ -2,7 +2,7 @@ use serde_derive::{Deserialize, Serialize};
 use utoipa::ToSchema;
 
 /// Response body for the omni-gen video cost estimate endpoint.
-#[derive(Serialize, Deserialize, ToSchema)]
+#[derive(Debug, Serialize, Deserialize, ToSchema)]
 pub struct OmniGenVideoCostResponse {
   pub success: bool,
 
diff --git a/crates/service/web/storyteller_web/src/http_server/endpoints/omni_gen/cost/video/omni_gen_video_cost_handler.rs b/crates/service/web/storyteller_web/src/http_server/endpoints/omni_gen/cost/video/omni_gen_video_cost_handler.rs
index f106b91e0b..40ebbbc174 100644
--- a/crates/service/web/storyteller_web/src/http_server/endpoints/omni_gen/cost/video/omni_gen_video_cost_handler.rs
+++ b/crates/service/web/storyteller_web/src/http_server/endpoints/omni_gen/cost/video/omni_gen_video_cost_handler.rs
@@ -1,11 +1,8 @@
-use std::sync::Arc;
-
 use crate::http_server::common_responses::common_web_error::CommonWebError;
 use crate::http_server::endpoints::omni_gen::shared_utils::map_router_cost_error::map_router_cost_error;
 use crate::http_server::endpoints::omni_gen::generate::video::helpers::hydrate_router_request::hydrate_to_router_request;
-use crate::state::server_state::ServerState;
 use actix_web::web::Json;
-use actix_web::{web, HttpRequest};
+use actix_web::HttpRequest;
 use artcraft_api_defs::omni_gen::cost_and_generate_requests::omni_gen_video_cost_and_generate_request::OmniGenVideoCostAndGenerateRequest;
 use artcraft_api_defs::omni_gen::cost_response::omni_gen_video_cost_response::OmniGenVideoCostResponse;
 use artcraft_router::api::router_provider::RouterProvider;
@@ -25,7 +22,6 @@ use artcraft_router::api::router_provider::RouterProvider;
 pub async fn omni_gen_video_cost_handler(
   _http_request: HttpRequest,
   request: Json<OmniGenVideoCostAndGenerateRequest>,
-  _server_state: web::Data<Arc<ServerState>>,
 ) -> Result<Json<OmniGenVideoCostResponse>, CommonWebError> {
   // NB: Deliberately no input validation here. The UI polls this endpoint
   // while the user is still composing the request (no prompt typed, nothing
@@ -51,3 +47,96 @@ pub async fn omni_gen_video_cost_handler(
     failures_are_refunded: estimate.failures_are_refunded,
   }))
 }
+
+#[cfg(test)]
+mod tests {
+  use actix_http::StatusCode;
+  use actix_web::test::TestRequest;
+  use actix_web::ResponseError;
+  use enums::common::generation::common_video_model::CommonVideoModel;
+
+  use super::*;
+
+  mod cost_without_inputs_tests {
+    use super::*;
+
+    /// Regression: xAI's v1.5 rejects text-to-video at generation time, but
+    /// the cost endpoint must still quote an image-less request — the cost
+    /// UI polls for a price before the user attaches an image. This request
+    /// shape used to be rejected (handler validation, then a router build
+    /// error that surfaced as a 500).
+    #[tokio::test]
+    async fn grok_1p5_without_an_image_gets_a_quote() {
+      let response = post_cost_request(base_request(CommonVideoModel::GrokImagineVideo1p5))
+        .await
+        .expect("image-less grok 1.5 cost estimate should succeed");
+      assert!(response.success);
+      assert!(response.cost_in_credits.unwrap() > 0);
+    }
+
+    #[tokio::test]
+    async fn bare_model_gets_a_quote_for_representative_models() {
+      for model in [
+        CommonVideoModel::GrokImagineVideo,
+        CommonVideoModel::Kling3p0Pro,
+        CommonVideoModel::Seedance2p0,
+        CommonVideoModel::Sora2,
+        CommonVideoModel::Veo3p1,
+        CommonVideoModel::ViduQ3,
+      ] {
+        let response = post_cost_request(base_request(model))
+          .await
+          .unwrap_or_else(|e| panic!("bare-model cost estimate should succeed for {model:?}: {e:?}"));
+        assert!(response.cost_in_credits.unwrap() > 0, "no cost for {model:?}");
+      }
+    }
+  }
+
+  mod error_mapping_tests {
+    use super::*;
+
+    #[tokio::test]
+    async fn unroutable_model_returns_400_not_500() {
+      // grok_video has no Artcraft route in the router; this must surface
+      // as a 400, not a 500 (it 500'd in production before the
+      // map_router_cost_error mapping).
+      let err = post_cost_request(base_request(CommonVideoModel::GrokVideo))
+        .await
+        .expect_err("unroutable model should be rejected");
+      assert_eq!(err.status_code(), StatusCode::BAD_REQUEST);
+    }
+  }
+
+  async fn post_cost_request(
+    body: OmniGenVideoCostAndGenerateRequest,
+  ) -> Result<OmniGenVideoCostResponse, CommonWebError> {
+    let http_request = TestRequest::post()
+      .uri("/v1/omni_gen/cost/video")
+      .to_http_request();
+    omni_gen_video_cost_handler(http_request, Json(body))
+      .await
+      .map(Json::into_inner)
+  }
+
+  fn base_request(model: CommonVideoModel) -> OmniGenVideoCostAndGenerateRequest {
+    OmniGenVideoCostAndGenerateRequest {
+      idempotency_token: None,
+      model: Some(model),
+      prompt: None,
+      negative_prompt: None,
+      start_frame_image_media_token: None,
+      end_frame_image_media_token: None,
+      reference_image_media_tokens: None,
+      reference_video_media_tokens: None,
+      reference_audio_media_tokens: None,
+      reference_character_tokens: None,
+      resolution: None,
+      aspect_ratio: None,
+      bitrate: None,
+      quality: None,
+      duration_seconds: None,
+      video_batch_count: None,
+      generate_audio: None,
+    }
+  }
+}