Document log level configuration for MinimalLambda and logging providers

[j-d-ha]

Problem

MinimalLambda log-level behavior is unclear in deployed Lambda functions, especially when combining:

• MinimalLambda default logging (LambdaApplication.CreateBuilder())
• Microsoft.Extensions.Logging configuration
• AWS Lambda runtime support / ILambdaLogger
• Lambda Advanced Logging Controls (loggingFormat: JSON, application/system log levels)
• third-party providers such as AWS Lambda Powertools for .NET

In a consumer app, setting AWS_LAMBDA_HANDLER_LOG_LEVEL=Warning did not suppress information logs as expected. Earlier attempts with Logging__LogLevel__Default=Warning and POWERTOOLS_LOG_LEVEL=Warning were also unclear because they affect different layers/providers.

Current code path observed

MinimalLambda default builder adds logging here:

Services.AddLogging(logging =>
{
 logging.AddConfiguration(Configuration.GetSection("Logging"));
 logging.AddSimpleConsole();

 logging.Configure(options =>
 {
 options.ActivityTrackingOptions = ActivityTrackingOptions.SpanId
 | ActivityTrackingOptions.TraceId
 | ActivityTrackingOptions.ParentId;
 });
});

So standard .NET configuration like this appears relevant for ILogger filtering:

Logging__LogLevel__Default=Warning

MinimalLambda also uses Amazon.Lambda.RuntimeSupport / LambdaBootstrap, so AWS runtime settings may be relevant for ILambdaLogger, e.g.:

AWS_LAMBDA_HANDLER_LOG_LEVEL=Warning

For Lambda Advanced Logging Controls with custom runtimes, AWS docs mention runtime-facing variables:

AWS_LAMBDA_LOG_LEVEL
AWS_LAMBDA_LOG_FORMAT

Powertools for AWS Lambda (.NET) has its own provider setting:

POWERTOOLS_LOG_LEVEL=Warning

Requested docs / clarification

Please document how log-level configuration flows through MinimalLambda, including:

1. Which settings affect ILogger<T> created through MinimalLambda defaults.
2. Which settings affect ILambdaLogger / context.Logger.
3. Whether AWS_LAMBDA_HANDLER_LOG_LEVEL applies to MinimalLambda custom-runtime apps, or only managed .NET runtimes / specific logging paths.
4. How Lambda Advanced Logging Controls interact with MinimalLambda (loggingFormat: JSON, ApplicationLogLevel, SystemLogLevel, AWS_LAMBDA_LOG_LEVEL, AWS_LAMBDA_LOG_FORMAT).
5. How third-party logging providers such as AWS Lambda Powertools fit in, and whether users should set provider-specific variables (POWERTOOLS_LOG_LEVEL) in addition to or instead of standard .NET logging config.
6. Recommended CDK examples for common cases:
   • MinimalLambda default logging only
   • MinimalLambda + Powertools
   • Lambda service-side filtering via Advanced Logging Controls

Helpful expected outcome

A docs section/table like:

Logging path	API used	Config key/env var	Value format	Notes
Default ILogger	ILogger<T>	Logging__LogLevel__Default	Warning	Standard Microsoft.Extensions.Logging
AWS Lambda logger	ILambdaLogger	AWS_LAMBDA_HANDLER_LOG_LEVEL or other	Warning?	Clarify applicability
Lambda ALC	Lambda service filter	CDK applicationLogLevel / AWS_LAMBDA_LOG_LEVEL	WARN	Service-side filtering
Powertools	Powertools provider	POWERTOOLS_LOG_LEVEL	Warning	Provider-specific

Goal: make deployed log-level behavior predictable and avoid trial-and-error across runtime/provider/service filtering layers.