Supported Components

This page lists the libraries and frameworks that the SkyAPM .NET agent can auto-instrument, what each one captures, and whether it is enabled by default or must be opted in. SkyAPM-dotnet is the C#/.NET auto-instrumentation agent for Apache SkyWalking; it reports to the SkyWalking OAP over gRPC using the sw8 / v8 protocol only.

For installation and wiring details, see the plugins guide and Configuration.

How instrumentation is enabled

The agent ships a set of diagnostic plugins. Some are registered automatically for every instrumented host; others are opt-in and must be enabled through the AddSkyAPM setup lambda.

On by default — registered as soon as the agent is active on a host. For ASP.NET Core, activation is zero-code via ASPNETCORE_HOSTINGSTARTUPASSEMBLIES=SkyApm.Agent.AspNetCore. The agent no-ops if SkyWalking:ServiceName is empty or SkyWalking:Enable is false.
Opt-in — enabled by calling the matching extension method inside the AddSkyAPM lambda:

services.AddSkyAPM(ext => ext
    .AddCap()
    .AddMongoDB()
    .AddSmartSql()
    .AddFreeSql(fsql)                       // requires your IFreeSql instance
    .AddFreeRedis(redisClient)              // requires your RedisClient instance
    .AddMasstransit());

Default (on by default)

These plugins are registered automatically by the agent host and require no extra code.

Component	Instruments	Upstream project
ASP.NET Core	Inbound HTTP entry spans; captures cookies/headers/body per config and honors `IgnorePaths`. Added by the ASP.NET Core host (`AddAspNetCoreHosting`).	dotnet/aspnetcore
HttpClient	Outbound HTTP exit spans with `sw8` header propagation (`HttpClient` / `IHttpClientFactory`).	dotnet/runtime
ADO.NET SqlClient	Database exit spans for `System.Data.SqlClient` and `Microsoft.Data.SqlClient`. Includes peer formatters (`SkyApm.PeerFormatters.SqlClient`, `SkyApm.PeerFormatters.MySqlConnector`).	System.Data.SqlClient, Microsoft.Data.SqlClient
gRPC server	Inbound gRPC entry spans for `Grpc.AspNetCore` / `Grpc.Core` (`AddGrpc`).	grpc/grpc-dotnet
gRPC client	Outbound gRPC exit spans for `Grpc.Net.Client` (`AddGrpcClient`).	grpc/grpc-dotnet
EntityFrameworkCore	EF Core database spans (`AddEntityFrameworkCore`).	dotnet/efcore
↳ Pomelo MySQL provider	EF Core spans for `Pomelo.EntityFrameworkCore.MySql`.	PomeloFoundation/Pomelo.EntityFrameworkCore.MySql
↳ Npgsql / PostgreSQL provider	EF Core spans for `Npgsql.EntityFrameworkCore.PostgreSQL`.	npgsql/Npgsql.EntityFrameworkCore.PostgreSQL
↳ Sqlite provider	EF Core spans for the SQLite provider.	dotnet/efcore
Microsoft.Extensions.Logging	Ships `Microsoft.Extensions.Logging` records to the SkyWalking OAP with trace context (`AddMSLogging`).	dotnet/runtime

Opt-in

Enable these by calling the corresponding method in the AddSkyAPM lambda.

Component	Setup call	Instruments	Upstream project
CAP	`ext.AddCap()`	Message-bus spans with cross-message `sw8` propagation.	dotnetcore/CAP
MassTransit	`ext.AddMasstransit()`	Message-bus spans with cross-message `sw8` propagation. Also ships its own `[assembly:HostingStartup]`: adding the package and listing it in `ASPNETCORE_HOSTINGSTARTUPASSEMBLIES` auto-wires it, switches `Activity` to W3C id format, and listens on the `MassTransit` `ActivitySource`.	MassTransit/MassTransit
MongoDB	`ext.AddMongoDB()`	`MongoDB.Driver` command spans.	mongodb/mongo-csharp-driver
SmartSql	`ext.AddSmartSql()`	ORM SQL spans.	dotnetcore/SmartSql
FreeSql	`ext.AddFreeSql(fsql)` — requires your `IFreeSql` instance	ORM SQL spans.	dotnetcore/FreeSql
FreeRedis	`ext.AddFreeRedis(redisClient, includeAuth: false)` — requires your `RedisClient` instance	Redis command spans.	2881099/FreeRedis

Notes

Classic ASP.NET (System.Web) is not instrumented. There is no dedicated plugin for the classic, non-Core ASP.NET pipeline; only ASP.NET Core is supported for inbound HTTP.
Protocol. The agent supports the SkyWalking sw8 / v8 protocol only. It reports to the OAP gRPC endpoint on port 11800 (the query/UI ports 12800/8080 are not used by the agent).
Configuration. Plugin behavior (sampling, ignored paths, captured headers/body, transport servers, and so on) is driven by skyapm.json and the other configuration sources. See Configuration for the full reference.