diff --git a/server/src/gateway/tests.rs b/server/src/gateway/tests.rs
index 6fb5b96d..a1e5c80c 100644
--- a/server/src/gateway/tests.rs
+++ b/server/src/gateway/tests.rs
@@ -848,6 +848,196 @@ async fn gateway_mcp_sse_proxy_streams_progress_and_final_response() {
     );
 }
 
+// ── SSE path honors explicit `project` and the create-guard (story 1229) ──
+//
+// Story 1225 added explicit-project routing and the create-without-project
+// guard, but only on the buffered `tools/call` path — the SSE branch above
+// (Accept: text/event-stream + `_meta.progressToken`) still always proxied
+// to `state.active_url()` and never ran the guard. These tests exercise the
+// SSE branch specifically so a regression here fails a test, unlike 1225's
+// tests at `create_tool_with_explicit_project_lands_in_non_active_project` /
+// `read_tool_with_explicit_project_reads_from_non_active_project` in
+// `http/gateway/mcp.rs`, which bypass SSE entirely.
+
+fn sse_body_for(id: i64, text: &str) -> String {
+    let final_resp = serde_json::json!({
+        "jsonrpc": "2.0",
+        "id": id,
+        "result": { "content": [{ "type": "text", "text": text }] }
+    });
+    format!("data: {final_resp}\n\n")
+}
+
+async fn make_two_http_project_state() -> (
+    Arc<GatewayState>,
+    mockito::ServerGuard,
+    mockito::ServerGuard,
+) {
+    let mut mock_alpha = mockito::Server::new_async().await;
+    let mut mock_beta = mockito::Server::new_async().await;
+    mock_alpha
+        .mock("POST", "/mcp")
+        .with_status(200)
+        .with_header("content-type", "text/event-stream")
+        .with_body(sse_body_for(1, "handled_by:alpha"))
+        .create_async()
+        .await;
+    mock_beta
+        .mock("POST", "/mcp")
+        .with_status(200)
+        .with_header("content-type", "text/event-stream")
+        .with_body(sse_body_for(1, "handled_by:beta"))
+        .create_async()
+        .await;
+
+    let mut projects = BTreeMap::new();
+    projects.insert(
+        "alpha".to_string(),
+        ProjectEntry::with_url(mock_alpha.url()),
+    );
+    projects.insert("beta".to_string(), ProjectEntry::with_url(mock_beta.url()));
+    let config = GatewayConfig {
+        projects,
+        sled_tokens: BTreeMap::new(),
+        release_channels: BTreeMap::new(),
+    };
+    let state = Arc::new(GatewayState::new(config, PathBuf::new(), 3000).unwrap());
+    assert_eq!(*state.active_project.read().await, "alpha");
+    (state, mock_alpha, mock_beta)
+}
+
+fn sse_data_lines(body: &str) -> Vec<&str> {
+    body.lines()
+        .filter_map(|l| l.strip_prefix("data: "))
+        .collect()
+}
+
+#[tokio::test]
+async fn sse_create_tool_with_explicit_project_lands_in_non_active_project() {
+    let (state, _mock_alpha, _mock_beta) = make_two_http_project_state().await;
+    let app = poem::Route::new()
+        .at("/mcp", poem::post(gateway_mcp_post_handler))
+        .data(state);
+    let cli = poem::test::TestClient::new(app);
+
+    let rpc_body = serde_json::to_vec(&serde_json::json!({
+        "jsonrpc": "2.0",
+        "id": 1,
+        "method": "tools/call",
+        "params": {
+            "name": "create_bug",
+            "arguments": { "project": "beta", "title": "x", "description": "y" },
+            "_meta": { "progressToken": "tok1" }
+        }
+    }))
+    .unwrap();
+    let resp = cli
+        .post("/mcp")
+        .header("content-type", "application/json")
+        .header("accept", "text/event-stream")
+        .body(rpc_body)
+        .send()
+        .await;
+    let body = resp.0.into_body().into_string().await.unwrap();
+    let lines = sse_data_lines(&body);
+    assert_eq!(
+        lines.len(),
+        1,
+        "expected exactly one SSE data event: {body}"
+    );
+    let ev: serde_json::Value = serde_json::from_str(lines[0]).unwrap();
+    assert_eq!(
+        ev["result"]["content"][0]["text"], "handled_by:beta",
+        "explicit project=beta on the SSE path must land in beta even though \
+         alpha is active: {ev}"
+    );
+}
+
+#[tokio::test]
+async fn sse_read_tool_with_explicit_project_reads_from_non_active_project() {
+    let (state, _mock_alpha, _mock_beta) = make_two_http_project_state().await;
+    let app = poem::Route::new()
+        .at("/mcp", poem::post(gateway_mcp_post_handler))
+        .data(state);
+    let cli = poem::test::TestClient::new(app);
+
+    let rpc_body = serde_json::to_vec(&serde_json::json!({
+        "jsonrpc": "2.0",
+        "id": 1,
+        "method": "tools/call",
+        "params": {
+            "name": "list_upcoming",
+            "arguments": { "project": "beta" },
+            "_meta": { "progressToken": "tok1" }
+        }
+    }))
+    .unwrap();
+    let resp = cli
+        .post("/mcp")
+        .header("content-type", "application/json")
+        .header("accept", "text/event-stream")
+        .body(rpc_body)
+        .send()
+        .await;
+    let body = resp.0.into_body().into_string().await.unwrap();
+    let lines = sse_data_lines(&body);
+    assert_eq!(
+        lines.len(),
+        1,
+        "expected exactly one SSE data event: {body}"
+    );
+    let ev: serde_json::Value = serde_json::from_str(lines[0]).unwrap();
+    assert_eq!(
+        ev["result"]["content"][0]["text"], "handled_by:beta",
+        "explicit project=beta on the SSE path must read from beta (audited \
+         generically, not via a hand-listed subset — story 1229 AC 4): {ev}"
+    );
+}
+
+#[tokio::test]
+async fn sse_create_tool_without_project_errors_when_multiple_projects_registered() {
+    let (state, _mock_alpha, _mock_beta) = make_two_http_project_state().await;
+    let app = poem::Route::new()
+        .at("/mcp", poem::post(gateway_mcp_post_handler))
+        .data(state);
+    let cli = poem::test::TestClient::new(app);
+
+    let rpc_body = serde_json::to_vec(&serde_json::json!({
+        "jsonrpc": "2.0",
+        "id": 1,
+        "method": "tools/call",
+        "params": {
+            "name": "create_bug",
+            "arguments": { "title": "x", "description": "y" },
+            "_meta": { "progressToken": "tok1" }
+        }
+    }))
+    .unwrap();
+    let resp = cli
+        .post("/mcp")
+        .header("content-type", "application/json")
+        .header("accept", "text/event-stream")
+        .body(rpc_body)
+        .send()
+        .await;
+    let body = resp.0.into_body().into_string().await.unwrap();
+    let lines = sse_data_lines(&body);
+    assert_eq!(
+        lines.len(),
+        1,
+        "expected exactly one SSE error event: {body}"
+    );
+    let ev: serde_json::Value = serde_json::from_str(lines[0]).unwrap();
+    assert!(
+        ev["error"]["message"]
+            .as_str()
+            .unwrap()
+            .contains("requires an explicit `project`"),
+        "SSE create call omitting `project` with >1 project registered must \
+         error, not silently proxy to the active project: {ev}"
+    );
+}
+
 /// Non-SSE `tools/call` requests must be routed over the live sled-uplink WS
 /// (story 1180: the gateway no longer falls back to HTTP for MCP proxying)
 /// and return a plain `application/json` body.
diff --git a/server/src/http/gateway/mcp.rs b/server/src/http/gateway/mcp.rs
index 840fdf4f..8b4513ba 100644
--- a/server/src/http/gateway/mcp.rs
+++ b/server/src/http/gateway/mcp.rs
@@ -295,7 +295,10 @@ pub async fn gateway_mcp_post_handler(
 
     // SSE proxy: tools/call with Accept: text/event-stream + progressToken for
     // non-gateway tools is forwarded to the sled's SSE endpoint so progress
-    // notifications flow through to the gateway client unchanged.
+    // notifications flow through to the gateway client unchanged. This must
+    // apply the same explicit-project resolution and create-guard as the
+    // buffered `tools/call` path below (story 1229: they had drifted apart,
+    // silently bypassing both on the SSE path).
     if rpc.method == "tools/call" {
         let accepts_sse = req
             .header("accept")
@@ -313,7 +316,15 @@ pub async fn gateway_mcp_post_handler(
                 .and_then(|v| v.as_str())
                 .unwrap_or("");
             if !GATEWAY_TOOLS.contains(&tool_name) {
-                return proxy_and_respond_sse(&state, &bytes, rpc.id).await;
+                return match extract_explicit_project(&rpc.params) {
+                    Some(project) => {
+                        proxy_and_respond_sse_for_project(&state, project, &bytes, rpc.id).await
+                    }
+                    None => match create_guard_error(&state, tool_name).await {
+                        Some(msg) => sse_error_response(rpc.id, -32602, msg),
+                        None => proxy_and_respond_sse(&state, &bytes, rpc.id).await,
+                    },
+                };
             }
         }
     }
@@ -340,35 +351,20 @@ pub async fn gateway_mcp_post_handler(
                 // Story 1208 AC 1: an explicit `project` argument on any
                 // proxied tool call targets that project directly, without
                 // requiring a prior `switch_project`.
-                let explicit_project = rpc
-                    .params
-                    .get("arguments")
-                    .and_then(|a| a.get("project"))
-                    .and_then(|v| v.as_str())
-                    .filter(|p| !p.is_empty());
-                match explicit_project {
+                match extract_explicit_project(&rpc.params) {
                     Some(project) => {
                         proxy_and_respond_for_project(&state, project, &bytes, rpc.id).await
                     }
-                    None if is_create_tool(tool_name) => {
+                    None => match create_guard_error(&state, tool_name).await {
                         // Story 1225 AC 3: with >1 project registered, a
                         // create call omitting `project` is ambiguous — fail
                         // loudly instead of silently filing into whichever
                         // project happens to be active.
-                        let project_count = state.projects.read().await.len();
-                        if project_count > 1 {
-                            to_json_response(JsonRpcResponse::error(
-                                rpc.id,
-                                -32602,
-                                format!(
-                                    "'{tool_name}' requires an explicit `project` argument when more than one project is registered (see list_projects) — the active project is not used implicitly for creates."
-                                ),
-                            ))
-                        } else {
+                        Some(msg) => to_json_response(JsonRpcResponse::error(rpc.id, -32602, msg)),
+                        None => {
                             proxy_and_respond_with_resolved_project(&state, &bytes, rpc.id).await
                         }
-                    }
-                    None => proxy_and_respond_with_resolved_project(&state, &bytes, rpc.id).await,
+                    },
                 }
             }
         }
@@ -376,6 +372,36 @@ pub async fn gateway_mcp_post_handler(
     }
 }
 
+/// Pull the optional per-call `project` argument out of a `tools/call`
+/// request's params (story 1208 AC 1), shared by the SSE and buffered
+/// `tools/call` paths so both resolve routing identically (story 1229).
+fn extract_explicit_project(params: &Value) -> Option<&str> {
+    params
+        .get("arguments")
+        .and_then(|a| a.get("project"))
+        .and_then(|v| v.as_str())
+        .filter(|p| !p.is_empty())
+}
+
+/// Returns an error message when `tool_name` is a create-tool called without
+/// an explicit `project` while more than one project is registered (story
+/// 1225 AC 3), or `None` when the call may proceed against the active
+/// project. Shared by the SSE and buffered `tools/call` paths so a fix to one
+/// can't silently miss the other, as happened in story 1229.
+async fn create_guard_error(state: &GatewayState, tool_name: &str) -> Option<String> {
+    if !is_create_tool(tool_name) {
+        return None;
+    }
+    let project_count = state.projects.read().await.len();
+    if project_count > 1 {
+        Some(format!(
+            "'{tool_name}' requires an explicit `project` argument when more than one project is registered (see list_projects) — the active project is not used implicitly for creates."
+        ))
+    } else {
+        None
+    }
+}
+
 /// Proxy a request to the active project and format the response.
 ///
 /// Prefers the live sled-uplink WebSocket when one is attached (story 899
@@ -473,14 +499,43 @@ async fn proxy_and_respond_for_project(
 ///
 /// On sled disconnect mid-stream a JSON-RPC error event is emitted so the
 /// client does not hang forever.
-#[allow(clippy::string_slice)] // pos from buf.find('\n'); '\n' is ASCII so pos and pos+1 are valid boundaries
 async fn proxy_and_respond_sse(state: &GatewayState, bytes: &[u8], id: Option<Value>) -> Response {
     let url = match state.active_url().await {
         Ok(u) => u,
         Err(e) => return sse_error_response(id, -32603, e.to_string()),
     };
+    stream_mcp_call_sse(state, &url, bytes, id).await
+}
 
-    let resp = match gateway::io::proxy_mcp_call_sse(&state.client, &url, bytes).await {
+/// Stream an MCP tool call via SSE to an explicitly named project (story
+/// 1229), rather than always targeting the active project — the SSE
+/// counterpart of `proxy_and_respond_for_project`.
+async fn proxy_and_respond_sse_for_project(
+    state: &GatewayState,
+    project: &str,
+    bytes: &[u8],
+    id: Option<Value>,
+) -> Response {
+    let url = match state.url_for_project(project).await {
+        Ok(u) => u,
+        Err(e) => return sse_error_response(id, -32602, e.to_string()),
+    };
+    stream_mcp_call_sse(state, &url, bytes, id).await
+}
+
+/// Shared SSE streaming body for `proxy_and_respond_sse` and
+/// `proxy_and_respond_sse_for_project` — proxies to `url` and re-emits each
+/// `data:` event from the sled to the originating gateway client without
+/// buffering. On sled disconnect mid-stream a JSON-RPC error event is emitted
+/// so the client does not hang forever.
+#[allow(clippy::string_slice)] // pos from buf.find('\n'); '\n' is ASCII so pos and pos+1 are valid boundaries
+async fn stream_mcp_call_sse(
+    state: &GatewayState,
+    url: &str,
+    bytes: &[u8],
+    id: Option<Value>,
+) -> Response {
+    let resp = match gateway::io::proxy_mcp_call_sse(&state.client, url, bytes).await {
         Ok(r) => r,
         Err(e) => return sse_error_response(id, -32603, format!("proxy error: {e}")),
     };
diff --git a/server/src/service/gateway/mod.rs b/server/src/service/gateway/mod.rs
index 9dab1da9..9b2c509f 100644
--- a/server/src/service/gateway/mod.rs
+++ b/server/src/service/gateway/mod.rs
@@ -361,6 +361,28 @@ impl GatewayState {
             })
     }
 
+    /// Get the URL of an explicitly named project (story 1229), without
+    /// reading or mutating `active_project`.
+    ///
+    /// Returns `Err` when the project is unknown or has no URL configured
+    /// (WS-uplink only) — mirrors [`GatewayState::active_url`]'s error shape
+    /// so callers can format both the same way.
+    pub async fn url_for_project(&self, project: &str) -> Result<String, Error> {
+        self.projects
+            .read()
+            .await
+            .get(project)
+            .ok_or_else(|| Error::ProjectNotFound(format!("unknown project '{project}'")))?
+            .url
+            .clone()
+            .ok_or_else(|| {
+                Error::ProjectNotFound(format!(
+                    "project '{project}' has no URL configured \
+                     (use sled-uplink WS or add url to projects.toml)"
+                ))
+            })
+    }
+
     /// Register a live sled connection for the given project.
     pub async fn register_sled_connection(&self, project_name: String, conn: SledConnection) {
         self.sled_connections