contextforge-org · lucarlig · Aug 11, 2026 · Aug 10, 2026
diff --git a/crates/contextforge-data-plane-apis/src/user_store.rs b/crates/contextforge-data-plane-apis/src/user_store.rs
@@ -3,17 +3,6 @@ use std::collections::HashMap;
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 
-#[derive(Debug, Clone, Deserialize, Serialize, JsonSchema, Default)]
-pub enum Transport {
-    #[default]
-    #[serde(rename = "STREAMABLEHTTP")]
-    StreamableHttp,
-    #[serde(rename = "SSE")]
-    Sse,
-    #[serde(rename = "STDIO")]
-    Stdio,
-}
-
 #[derive(Debug, Clone, Deserialize, Serialize, JsonSchema, Default)]
 pub enum IntegrationType {
     #[serde(rename = "REST")]
@@ -27,7 +16,6 @@ pub enum IntegrationType {
 pub struct BackendMCPGateway {
     pub name: String,
     pub url: url::Url,
-    pub transport: Transport,
     /// Header names copied from the downstream request onto the upstream connection.
     pub passthrough_headers: Vec<String>,
     /// Static headers injected onto the upstream connection (override passthrough).

diff --git a/crates/contextforge-data-plane-lib/src/gateway/identifier_routing.rs b/crates/contextforge-data-plane-lib/src/gateway/identifier_routing.rs
@@ -182,7 +182,6 @@ mod tests {
                 "79fabb70-2188-4de8-95ed-dc1e976e14d4": {
                     "name": "compliance_reference",
                     "url": "http://upstream:9000/mcp",
-                    "transport": "STREAMABLEHTTP",
                     "passthrough_headers": [],
                     "allowed_tool_names": ["get_stats", "echo"],
                     "tool_name_aliases": {
@@ -214,7 +213,6 @@ mod tests {
                 "compliance-reference": {
                     "name": "compliance_reference",
                     "url": "http://upstream:9000/mcp",
-                    "transport": "STREAMABLEHTTP",
                     "passthrough_headers": [],
                     "allowed_tool_names": ["get_stats"],
                     "allowed_resource_names": [],
@@ -223,7 +221,6 @@ mod tests {
                 "other": {
                     "name": "other",
                     "url": "http://other:9000/mcp",
-                    "transport": "STREAMABLEHTTP",
                     "passthrough_headers": [],
                     "allowed_tool_names": [],
                     "allowed_resource_names": [],

diff --git a/crates/contextforge-data-plane-lib/src/gateway/list_aggregation.rs b/crates/contextforge-data-plane-lib/src/gateway/list_aggregation.rs
@@ -266,7 +266,6 @@ mod tests {
                 backend_id: {
                     "name": "backend",
                     "url": "http://upstream:9000/mcp",
-                    "transport": "STREAMABLEHTTP",
                     "passthrough_headers": [],
                     "allowed_tool_names": [],
                     "allowed_resource_names": [],

diff --git a/crates/contextforge-data-plane-lib/src/gateway/mcp_service/initialization.rs b/crates/contextforge-data-plane-lib/src/gateway/mcp_service/initialization.rs
@@ -275,8 +275,6 @@ fn is_protected_header(name: &http::HeaderName) -> bool {
 
 #[cfg(test)]
 mod tests {
-    use contextforge_data_plane_apis::user_store::Transport;
-
     use super::*;
 
     #[test]
@@ -297,7 +295,6 @@ mod tests {
         BackendMCPGateway {
             name: "b".into(),
             url: "https://upstream.example/mcp".parse().unwrap(),
-            transport: Transport::default(),
             passthrough_headers: passthrough.iter().map(|s| (*s).to_owned()).collect(),
             add_headers: add.iter().map(|(k, v)| ((*k).to_owned(), (*v).to_owned())).collect(),
             remove_headers: remove.iter().map(|s| (*s).to_owned()).collect(),

diff --git a/crates/contextforge-data-plane-lib/tests/gateway_pagination.rs b/crates/contextforge-data-plane-lib/tests/gateway_pagination.rs
@@ -4,7 +4,7 @@ use std::{collections::HashMap, sync::Arc};
 
 use contextforge_data_plane_apis::{
     User,
-    user_store::{BackendMCPGateway, Transport, UserConfig, VirtualHost},
+    user_store::{BackendMCPGateway, UserConfig, VirtualHost},
 };
 use contextforge_data_plane_lib::{Config, Gateway, Result, UserConfigStore, UserConfigStoreType};
 use rmcp::{
@@ -24,7 +24,6 @@ fn paginating_backend(port: u16) -> BackendMCPGateway {
     BackendMCPGateway {
         name: format!("backend-{port}"),
         url: format!("http://127.0.0.1:{port}/mcp").parse().expect("valid url"),
-        transport: Transport::default(),
         passthrough_headers: Vec::new(),
         add_headers: HashMap::new(),
         remove_headers: Vec::new(),

diff --git a/crates/contextforge-data-plane-lib/tests/support/list_tools_gateway.rs b/crates/contextforge-data-plane-lib/tests/support/list_tools_gateway.rs
@@ -2,7 +2,7 @@ use std::{collections::HashMap, net::SocketAddr, sync::Arc};
 
 use contextforge_data_plane_apis::{
     User,
-    user_store::{BackendMCPGateway, Transport, UserConfig, VirtualHost},
+    user_store::{BackendMCPGateway, UserConfig, VirtualHost},
 };
 use contextforge_data_plane_lib::{
     Config, Gateway, Result, UpstreamConnectionMode, UserConfigStore, UserConfigStoreType,
@@ -215,7 +215,6 @@ fn create_backends(ports: &[u16], with_tls: bool) -> HashMap<String, BackendMCPG
                 BackendMCPGateway {
                     name: format!("backend-{port}"),
                     url,
-                    transport: Transport::default(),
                     passthrough_headers: Vec::new(),
                     add_headers: HashMap::default(),
                     remove_headers: Vec::new(),

diff --git a/crates/contextforge-data-plane-lib/tests/support/plugin_gateway.rs b/crates/contextforge-data-plane-lib/tests/support/plugin_gateway.rs
@@ -6,7 +6,7 @@ use std::{
 
 use contextforge_data_plane_apis::{
     User,
-    user_store::{BackendMCPGateway, Transport, UserConfig, VirtualHost},
+    user_store::{BackendMCPGateway, UserConfig, VirtualHost},
 };
 use contextforge_data_plane_cpex::CpexRuntimeRegistry;
 use contextforge_data_plane_lib::{Config, Gateway, UpstreamConnectionMode, UserConfigStore, UserConfigStoreType};
@@ -268,7 +268,6 @@ async fn start_gateway_with_runtime(
                             BackendMCPGateway {
                                 url: format!("http://127.0.0.1:{backend_port}/mcp").parse().expect("backend URL"),
                                 name: String::new(),
-                                transport: Transport::default(),
                                 passthrough_headers: Vec::new(),
                                 add_headers: HashMap::default(),
                                 remove_headers: Vec::new(),

diff --git a/crates/contextforge-data-plane/tests/secrets_detection_e2e.rs b/crates/contextforge-data-plane/tests/secrets_detection_e2e.rs
@@ -16,7 +16,7 @@ use std::{
 use contextforge_data_plane_apis::{
     User,
     runtime_plugin_config::{RUNTIME_PLUGIN_CONFIG_KEY, RUNTIME_PLUGIN_CONFIG_VERSION},
-    user_store::{BackendMCPGateway, Transport, UserConfig, VirtualHost},
+    user_store::{BackendMCPGateway, UserConfig, VirtualHost},
 };
 use http::{HeaderMap, HeaderValue};
 use jsonwebtoken::{Algorithm, EncodingKey, Header, encode};
@@ -375,7 +375,6 @@ async fn write_redis_config(redis_port: u16, backend: &RunningBackend) {
                     BackendMCPGateway {
                         name: "backend".to_owned(),
                         url: backend.url.parse().expect("backend URL parses"),
-                        transport: Transport::StreamableHttp,
                         passthrough_headers: Vec::new(),
                         add_headers: HashMap::new(),
                         remove_headers: Vec::new(),

diff --git a/docs/book/src/backend-connections-and-transports.md b/docs/book/src/backend-connections-and-transports.md
@@ -18,9 +18,9 @@ architecture roles.
 | Upstream backend | Shared `reqwest::Client` plus RMCP `StreamableHttpClientTransport`. | `common.rs`, `gateway/mcp_service/initialization.rs`, and `gateway/backend_transports.rs`. | Open MCP client sessions to configured backend MCP servers. |
 | Config store | Redis plain, TLS, or mTLS connection manager. | `common.rs` and `user_config_store/`. | Load `UserConfig` and plugin runtime config from control-plane authored storage. |
 
-The current MCP dataplane only uses streamable HTTP for backend MCP traffic.
-`BackendMCPGateway.transport` already has `STREAMABLEHTTP`, `SSE`, and `STDIO`,
-but upstream routing does not branch on that field yet.
+The MCP dataplane always uses Streamable HTTP for backend MCP traffic.
+`BackendMCPGateway` has no transport selector, and upstream routing always
+builds `StreamableHttpClientTransport`.
 
 ## Downstream Listeners
 
@@ -126,7 +126,6 @@ but it is not the final shape for every backend-specific decision.
 | Downstream TLS certificate | Process config. | Process config. It belongs to the gateway listener. |
 | Upstream trust bundle and mTLS identity | Process config. | Runtime config per backend or referenced secret material. |
 | Backend auth headers | Delegated to `passthrough_headers` / `add_headers` / `remove_headers` in `BackendMCPGateway`. | — |
-| Backend transport type | Model field exists, not routed yet. | Runtime config per backend. |
 | Header pass-through policy | Implemented via `passthrough_headers`, `add_headers`, `remove_headers` on `BackendMCPGateway`. Headers are session-scoped (snapshotted at initialize); request-scoped propagation is future work. | — |
 
 The boundary to preserve is simple: listener code should not know Redis schema,

diff --git a/docs/book/src/running-the-gateway.md b/docs/book/src/running-the-gateway.md
@@ -123,7 +123,6 @@ curl --silent --show-error --request POST \
           "gateway-one": {
             "name": "gateway-one",
             "url": "http://127.0.0.1:5555/mcp",
-            "transport": "STREAMABLEHTTP",
             "passthrough_headers": [],
             "allowed_tool_names": [],
             "allowed_resource_names": [],
@@ -132,7 +131,6 @@ curl --silent --show-error --request POST \
           "gateway-two": {
             "name": "gateway-two",
             "url": "http://127.0.0.1:5556/mcp",
-            "transport": "STREAMABLEHTTP",
             "passthrough_headers": [],
             "allowed_tool_names": [],
             "allowed_resource_names": [],

diff --git a/docs/book/src/runtime-configuration.md b/docs/book/src/runtime-configuration.md
@@ -35,20 +35,14 @@ VirtualHost
 BackendMCPGateway
   name: String
   url: Url
-  transport: Transport
   passthrough_headers: Vec<String>
   allowed_tool_names: Vec<String>
   allowed_resource_names: Vec<String>
   allowed_prompt_names: Vec<String>
 ```
 
-`Transport` currently declares:
-
-```text
-STREAMABLEHTTP
-SSE
-STDIO
-```
+Backend MCP transport is intentionally absent from `UserConfig`. The dataplane
+always builds an upstream Streamable HTTP client.
 
 The Rust types above are easier to picture as JSON. For a complete, working
 `UserConfig` document, see the seed request body in
@@ -65,7 +59,6 @@ but the distinction should stay explicit:
 | `VirtualHost.backends` map key | Required. Selects backend session state and becomes the public prefix when a multi-backend identifier has no explicit alias. |
 | `BackendMCPGateway.url` | Required. Used to build the upstream `StreamableHttpClientTransport`. |
 | `BackendMCPGateway.name` | Present in the model. Current routing uses the backend map key, not this field, as the namespace. |
-| `transport` | Present in the model. Current upstream code always builds a streamable HTTP client transport. |
 | `passthrough_headers` | Applied during `initialize`: named downstream request headers are copied onto the upstream connection header map. Body-framing (`Content-Length`, `Content-Type`), hop-by-hop, non-standard hop-by-hop (`Proxy-Connection`), and RMCP-reserved headers are silently skipped. Propagation is session-scoped — headers are snapshotted from the initialize request; see note below. |
 | `add_headers` | Static `{name: value}` headers injected onto the upstream connection after passthrough (override passthrough values). Body-framing, hop-by-hop, non-standard hop-by-hop (`Proxy-Connection`), and RMCP-reserved headers are silently skipped. |
 | `remove_headers` | Header names stripped from the upstream connection after add (applied last). Body-framing, hop-by-hop, non-standard hop-by-hop (`Proxy-Connection`), and RMCP-reserved headers are silently skipped. |

diff --git a/schemas/user_config.json b/schemas/user_config.json
@@ -38,9 +38,6 @@
           "type": "string",
           "format": "uri"
         },
-        "transport": {
-          "$ref": "#/$defs/Transport"
-        },
         "passthrough_headers": {
           "description": "Header names copied from the downstream request onto the upstream connection.",
           "type": "array",
@@ -93,20 +90,11 @@
       "required": [
         "name",
         "url",
-        "transport",
         "passthrough_headers",
         "allowed_tool_names",
         "allowed_resource_names",
         "allowed_prompt_names"
       ]
-    },
-    "Transport": {
-      "type": "string",
-      "enum": [
-        "STREAMABLEHTTP",
-        "SSE",
-        "STDIO"
-      ]
     }
   }
 }