diff --git a/Cargo.lock b/Cargo.lock
index beed2565..215c6d51 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5666,6 +5666,7 @@ dependencies = [
  "bytes",
  "http 1.2.0",
  "opentelemetry",
+ "reqwest 0.12.7",
 ]
 
 [[package]]
@@ -5682,6 +5683,7 @@ dependencies = [
  "opentelemetry-proto",
  "opentelemetry_sdk",
  "prost",
+ "reqwest 0.12.7",
  "serde_json",
  "thiserror 1.0.62",
  "tokio",
@@ -6575,6 +6577,7 @@ dependencies = [
  "async-compression",
  "base64 0.22.1",
  "bytes",
+ "futures-channel",
  "futures-core",
  "futures-util",
  "h2 0.4.7",
diff --git a/Cargo.toml b/Cargo.toml
index 2e6f56d3..8112a166 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -195,7 +195,7 @@ yoke = { version = "0.7.4", features = ["derive"] }
 
 opentelemetry = "0.27.0"
 opentelemetry-http = "0.27.0"
-opentelemetry-otlp = { version = "0.27.0", features = ["logs", "trace", "http-proto", "http-json"] }
+opentelemetry-otlp = { version = "0.27.0", features = ["logs", "trace", "http-proto", "http-json", "reqwest-client"] }
 opentelemetry-semantic-conventions = { version = "0.27.0", features = ["semconv_experimental"] }
 opentelemetry_sdk = { version = "0.27.0", features = ["rt-tokio"] }
 
diff --git a/crates/base/src/runtime/mod.rs b/crates/base/src/runtime/mod.rs
index f0d496c5..135d9ea3 100644
--- a/crates/base/src/runtime/mod.rs
+++ b/crates/base/src/runtime/mod.rs
@@ -1320,7 +1320,6 @@ where
       op_state_ref
         .try_borrow::<EventMetadata>()
         .map(otel::WorkerSpanAttrs::from_event_metadata)
-        .unwrap_or_default()
     };
 
     let inspector = self.inspector();
@@ -1383,7 +1382,8 @@ where
               &maybe_cpu_usage_metrics_tx,
               &mut accumulated_cpu_time_ns,
               || {
-                let _span = otel::start_span("v8.mod_evaluate", &otel_attrs);
+                let _span =
+                  otel::start_span("v8.mod_evaluate", otel_attrs.as_ref());
                 locker.js_runtime.mod_evaluate(main_module_id)
               },
             ))
@@ -1465,7 +1465,7 @@ where
             &mut accumulated_cpu_time_ns,
             || {
               let _span =
-                otel::start_span("v8.dispatch_load_event", &otel_attrs);
+                otel::start_span("v8.dispatch_load_event", otel_attrs.as_ref());
               MaybeDenoRuntime::DenoRuntime(*locker).dispatch_load_event()
             },
           ) {
@@ -1501,7 +1501,8 @@ where
         &maybe_cpu_usage_metrics_tx,
         &mut accumulated_cpu_time_ns,
         || {
-          let _span = otel::start_span("v8.dispatch_unload_event", &otel_attrs);
+          let _span =
+            otel::start_span("v8.dispatch_unload_event", otel_attrs.as_ref());
           MaybeDenoRuntime::DenoRuntime(&mut locker).dispatch_unload_event()
         },
       ) {
@@ -1526,15 +1527,12 @@ where
     let has_inspector = self.inspector().is_some();
     let is_user_worker = self.conf.is_user_worker();
     let global_waker = self.waker.clone();
-
-    // Collect worker identity for OTLP spans.
     let otel_attrs = {
       let op_state = self.js_runtime.op_state();
       let op_state_ref = op_state.borrow();
       op_state_ref
         .try_borrow::<EventMetadata>()
         .map(otel::WorkerSpanAttrs::from_event_metadata)
-        .unwrap_or_default()
     };
 
     let mut termination_request_fut = self
@@ -1604,7 +1602,8 @@ where
           Cow::Borrowed(waker)
         };
 
-        let _poll_span = otel::start_span("v8.poll_event_loop", &otel_attrs);
+        let _poll_span =
+          otel::start_span("v8.poll_event_loop", otel_attrs.as_ref());
         js_runtime.poll_event_loop(
           &mut std::task::Context::from_waker(waker.as_ref()),
           PollEventLoopOptions {
diff --git a/crates/base/src/runtime/otel.rs b/crates/base/src/runtime/otel.rs
index 2adf9623..32fc7124 100644
--- a/crates/base/src/runtime/otel.rs
+++ b/crates/base/src/runtime/otel.rs
@@ -42,7 +42,7 @@ pub fn init_if_needed() {
 }
 
 /// Worker identity and custom otel attributes collected once at `run()` entry.
-#[derive(Clone, Default)]
+#[derive(Clone)]
 pub struct WorkerSpanAttrs(Vec<KeyValue>);
 
 impl WorkerSpanAttrs {
@@ -65,12 +65,13 @@ impl WorkerSpanAttrs {
   }
 }
 
-/// Start a named span with worker attributes. Returns `None` if OTLP is not
-/// configured.
+/// Start a named span with worker attributes.
+/// Returns `None` if OTLP is not configured or `attrs` is `None`.
 pub fn start_span(
   name: &'static str,
-  attrs: &WorkerSpanAttrs,
+  attrs: Option<&WorkerSpanAttrs>,
 ) -> Option<OtelSpanGuard> {
+  let attrs = attrs?;
   let provider = PROVIDER.get()?.as_ref()?;
   let tracer = provider.tracer("edge-runtime");
   let mut span = tracer