Semantic conventions for FaaS exceptions

Status: Development

This document defines semantic conventions for recording exceptions on FaaS invocations.

FaaS invocation exception

Status:

The event name MUST be faas.invocation.exception.

This event represents an exception that occurred during FaaS function invocation, such as application errors, internal failures, or other exceptions that prevent the function from completing successfully.

This event SHOULD be recorded when an exception occurs during FaaS function invocation. Instrumentations SHOULD set the severity to ERROR (severity number 17) when recording this event. Instrumentations MAY provide a configuration option to populate exception events with the attributes captured on the corresponding FaaS span.

Attributes:

Key	Stability	Requirement Level	Value Type	Description	Example Values
exception.message		Conditionally Required [1]	string	The exception message. [2]	Division by zero; Can't convert 'int' object to str implicitly
exception.type		Conditionally Required [3]	string	The type of the exception (its fully-qualified class name, if applicable). The dynamic type of the exception should be preferred over the static type in languages that support it. [4]	java.net.ConnectException; OSError
exception.stacktrace		Recommended	string	A stacktrace as a string in the natural representation for the language runtime. The representation is to be determined and documented by each language SIG.	Exception in thread "main" java.lang.RuntimeException: Test exception\n at com.example.GenerateTrace.methodB(GenerateTrace.java:13)\n at com.example.GenerateTrace.methodA(GenerateTrace.java:9)\n at com.example.GenerateTrace.main(GenerateTrace.java:5)

[1] exception.message: Required if exception.type is not set, recommended otherwise.

[2] exception.message:

[3] exception.type: Required if exception.message is not set, recommended otherwise.

[4] exception.type: If the recorded exception type is a wrapper that is not meaningful for failure classification, instrumentation MAY use the type of the inner exception instead. For example, in Go, errors created with fmt.Errorf using %w MAY be unwrapped when the wrapper type does not help classify the failure.