diff --git a/crates/common/src/consts.rs b/crates/common/src/consts.rs
index 8f59e981..f4861dd7 100644
--- a/crates/common/src/consts.rs
+++ b/crates/common/src/consts.rs
@@ -15,7 +15,7 @@ pub const HALLUCINATION_INTERNAL_HOST: &str = "hallucination";
 pub const EMBEDDINGS_INTERNAL_HOST: &str = "embeddings";
 pub const GUARD_INTERNAL_HOST: &str = "guard";
 pub const ARCH_ROUTING_HEADER: &str = "x-arch-llm-provider";
-pub const ARCH_MESSAGES_KEY: &str = "arch_messages";
+pub const MESSAGES_KEY: &str = "messages";
 pub const ARCH_PROVIDER_HINT_HEADER: &str = "x-arch-llm-provider-hint";
 pub const CHAT_COMPLETIONS_PATH: &str = "/v1/chat/completions";
 pub const ARCH_STATE_HEADER: &str = "x-arch-state";
diff --git a/crates/prompt_gateway/src/stream_context.rs b/crates/prompt_gateway/src/stream_context.rs
index dbc991a6..569f362f 100644
--- a/crates/prompt_gateway/src/stream_context.rs
+++ b/crates/prompt_gateway/src/stream_context.rs
@@ -13,7 +13,7 @@ use common::common_types::{
 use common::configuration::{Overrides, PromptGuards, PromptTarget};
 use common::consts::{
     ARCH_FC_INTERNAL_HOST, ARCH_FC_MODEL_NAME, ARCH_FC_REQUEST_TIMEOUT_MS,
-    ARCH_INTERNAL_CLUSTER_NAME, ARCH_MESSAGES_KEY, ARCH_MODEL_PREFIX, ARCH_STATE_HEADER,
+    ARCH_INTERNAL_CLUSTER_NAME, MESSAGES_KEY, ARCH_MODEL_PREFIX, ARCH_STATE_HEADER,
     ARCH_UPSTREAM_HOST_HEADER, DEFAULT_EMBEDDING_MODEL, DEFAULT_HALLUCINATED_THRESHOLD,
     DEFAULT_INTENT_MODEL, DEFAULT_PROMPT_TARGET_THRESHOLD, EMBEDDINGS_INTERNAL_HOST,
     HALLUCINATION_INTERNAL_HOST, REQUEST_ID_HEADER, SYSTEM_ROLE, TOOL_ROLE, USER_ROLE,
@@ -461,7 +461,7 @@ impl StreamContext {
                     let upstream_endpoint = endpoint.name;
                     let mut params = HashMap::new();
                     params.insert(
-                        ARCH_MESSAGES_KEY.to_string(),
+                        MESSAGES_KEY.to_string(),
                         callout_context.request_body.messages.clone(),
                     );
                     let arch_messages_json = serde_json::to_string(&params).unwrap();
@@ -688,7 +688,7 @@ impl StreamContext {
             tool_params_json_str
         );
         tool_params.insert(
-            String::from(ARCH_MESSAGES_KEY),
+            String::from(MESSAGES_KEY),
             serde_yaml::to_value(&callout_context.request_body.messages).unwrap(),
         );
         let tool_params_json_str = serde_json::to_string(&tool_params).unwrap();
@@ -772,7 +772,7 @@ impl StreamContext {
             .arguments
             .clone();
         tool_params.insert(
-            String::from(ARCH_MESSAGES_KEY),
+            String::from(MESSAGES_KEY),
             serde_yaml::to_value(&callout_context.request_body.messages).unwrap(),
         );