Move MCP span assertion into unit test

Keep the narrow MCP span PR out of the integration test suite by asserting the span fields in mcp_tool_call_tests instead.

Co-authored-by: Codex <noreply@openai.com>

codex-rs/core/src/mcp_tool_call_tests.rs

@@ -18,6 +18,10 @@ use serde::Deserialize;
 use std::collections::HashMap;
 use std::sync::Arc;
 use tempfile::tempdir;
+use tracing::Instrument;
+use tracing::Level;
+use tracing_subscriber::fmt::format::FmtSpan;
+use tracing_test::internal::MockWriter;
 
 fn annotations(
     read_only: Option<bool>,
@@ -119,6 +123,57 @@ fn approval_question_text_prepends_safety_reason() {
     );
 }
 
+#[tokio::test]
+async fn mcp_tool_call_span_records_expected_fields() {
+    let buffer: &'static std::sync::Mutex<Vec<u8>> =
+        Box::leak(Box::new(std::sync::Mutex::new(Vec::new())));
+    let subscriber = tracing_subscriber::fmt()
+        .with_level(true)
+        .with_ansi(false)
+        .with_max_level(Level::TRACE)
+        .with_span_events(FmtSpan::FULL)
+        .with_writer(MockWriter::new(buffer))
+        .finish();
+    let _guard = tracing::subscriber::set_default(subscriber);
+
+    let (session, turn_context) = make_session_and_context().await;
+
+    async {}
+        .instrument(mcp_tool_call_span(
+            &session,
+            &turn_context,
+            McpToolCallSpanFields {
+                server_name: "rmcp",
+                tool_name: "echo",
+                call_id: "call-123",
+                server_origin: Some("https://example.com:8443/mcp"),
+                connector_id: Some("calendar"),
+                connector_name: Some("Calendar"),
+            },
+        ))
+        .await;
+
+    let logs = String::from_utf8(buffer.lock().expect("buffer lock").clone()).expect("utf8 logs");
+    assert!(
+        logs.contains("mcp.tools.call{otel.kind=\"client\"")
+            && logs.contains("rpc.system=\"jsonrpc\"")
+            && logs.contains("rpc.method=\"tools/call\"")
+            && logs.contains("mcp.server.name=\"rmcp\"")
+            && logs.contains("mcp.server.origin=\"https://example.com:8443/mcp\"")
+            && logs.contains("mcp.transport=\"streamable_http\"")
+            && logs.contains("mcp.connector.id=\"calendar\"")
+            && logs.contains("mcp.connector.name=\"Calendar\"")
+            && logs.contains("tool.name=\"echo\"")
+            && logs.contains("tool.call_id=\"call-123\"")
+            && logs.contains("server.address=\"example.com\"")
+            && logs.contains("server.port=8443")
+            && logs.contains("conversation.id=")
+            && logs.contains("session.id=")
+            && logs.contains("turn.id="),
+        "missing MCP tool span fields\nlogs:\n{logs}"
+    );
+}
+
 #[tokio::test]
 async fn approval_elicitation_request_uses_message_override_and_preserves_tool_params_keys() {
     let (session, turn_context) = make_session_and_context().await;

codex-rs/core/tests/suite/rmcp_client.rs

@@ -48,28 +48,14 @@ use tokio::process::Child;
 use tokio::process::Command;
 use tokio::time::Instant;
 use tokio::time::sleep;
-use tracing::Level;
-use tracing_subscriber::fmt::format::FmtSpan;
-use tracing_test::internal::MockWriter;
 
 static OPENAI_PNG: &str = "data:image/png;base64,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";
 
-#[tokio::test(flavor = "current_thread")]
+#[tokio::test(flavor = "multi_thread", worker_threads = 1)]
 #[serial(mcp_test_value)]
 async fn stdio_server_round_trip() -> anyhow::Result<()> {
     skip_if_no_network!(Ok(()));
 
-    let buffer: &'static std::sync::Mutex<Vec<u8>> =
-        Box::leak(Box::new(std::sync::Mutex::new(Vec::new())));
-    let subscriber = tracing_subscriber::fmt()
-        .with_level(true)
-        .with_ansi(false)
-        .with_max_level(Level::TRACE)
-        .with_span_events(FmtSpan::FULL)
-        .with_writer(MockWriter::new(buffer))
-        .finish();
-    let _guard = tracing::subscriber::set_default(subscriber);
-
     let server = responses::start_mock_server().await;
 
     let call_id = "call-123";
@@ -203,20 +189,6 @@ async fn stdio_server_round_trip() -> anyhow::Result<()> {
 
     wait_for_event(&fixture.codex, |ev| matches!(ev, EventMsg::TurnComplete(_))).await;
 
-    let logs = String::from_utf8(buffer.lock().unwrap().clone()).unwrap();
-    assert!(
-        logs.contains("turn{otel.name=\"session_task.turn\"")
-            && logs.contains("mcp.tools.call{otel.kind=\"client\"")
-            && logs.contains("rpc.system=\"jsonrpc\"")
-            && logs.contains("rpc.method=\"tools/call\"")
-            && logs.contains("mcp.server.name=\"rmcp\"")
-            && logs.contains("mcp.transport=\"stdio\"")
-            && logs.contains("tool.name=\"echo\"")
-            && logs.contains("tool.call_id=\"call-123\"")
-            && logs.contains("turn.id="),
-        "missing MCP tracing spans nested under session_task.turn\nlogs:\n{logs}"
-    );
-
     server.verify().await;
 
     Ok(())