diff --git a/README.md b/README.md
index 9dc9c40..6ed449e 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,14 @@
# Serverless Middleware
-Some helpers for writing API endpoints using AWS Lambda.
+A helper for writing APIs using AWS Lambda functions.
+
+### Features
+
+- Dependency injection for easy unit testing.
+- Pretty JSON error output, with status codes automatically determined based on error message.
+- Easy access to query strings and JSON body properties.
+- Serverless warmup plugin support.
+- OpenTelemetry support and additional span attributes, for use with [opentelemetry-lambda](https://github.com/open-telemetry/opentelemetry-lambda).
---
@@ -47,6 +55,10 @@ serverless plugin.
Simply install the serverless plugin, no other changes to your code necessary.
The middleware will automatically prevent code execution on warmup requests.
+### OpenTelemetry span enrichment
+
+If an active OpenTelemetry span is detected, event and response properties will automatically be added.
+
---
diff --git a/src/lib/ApiAdapter.js b/src/lib/ApiAdapter.js
index 1a738f7..e862871 100644
--- a/src/lib/ApiAdapter.js
+++ b/src/lib/ApiAdapter.js
@@ -69,8 +69,13 @@ class ApiAdapter {
return res;
} catch (error) {
console.error(error);
+
OpenTelemetry.addSpanErrorAttributes(event, error);
- return this.errorConverter.convert(error);
+
+ const res = this.errorConverter.convert(error);
+ OpenTelemetry.addSpanResponseAttributes(event, res);
+
+ return res;
}
}