Running Agents

Agents must execute within a Runner environment that manages session state, artifacts, memory, and telemetry.

Available Runners

• ADK Web: Interactive Blazor dashboard for visual debugging.
• ADK Server A2A: HTTP APIs for synchronous, streaming, and Agent-to-Agent execution.
• Console Runner: Interactive terminal experience using Spectre.Console.
• Custom Runner: Core Runner class for deep integration into background services.

Core Runner Invocation

Execution requires a Runner, a SessionId (tied to a user and app), and input Content.

var runner = new InMemoryRunner("cli-app", myAgent);

// Fetch or create a session
var session = await runner.SessionService.CreateSessionAsync(new CreateSessionRequest
{
    AppName = "cli-app", UserId = "dev-user"
});

// Run and stream events
await foreach (var evt in runner.RunAsync("dev-user", session.Id, userMessage))
{
    // Handle output
}

Run Configurations

Control execution behavior, limits, and multimodality using RunConfig:

var runConfig = new RunConfig
{
    MaxLlmCalls = 10,
    PauseOnToolCalls = true,
    ResponseModalities = ["AUDIO"],
    SaveInputBlobsAsArtifacts = true
};

Persistent Sessions

Replace default InMemory services with EfCoreSessionService for production databases (e.g., SQLite, Postgres).

var dbOptions = new DbContextOptionsBuilder<AdkSessionDbContext>()
    .UseSqlite("Data Source=adk_sessions.db")
    .Options;

var runnerConfig = new RunnerConfig
{
    AppName = "production_app",
    Agent = myAgent,
    SessionService = new EfCoreSessionService(new PooledDbContextFactory<AdkSessionDbContext>(dbOptions)),
    ArtifactService = new FileArtifactService("artifacts") // Persist to disk
};

var runner = new Runner(runnerConfig);