Crestapps Core A2a

CrestApps.Core A2A - Prompt Templates

Add A2A Client Support

You are a CrestApps.Core expert. Generate code and guidance for Agent-to-Agent protocol support in CrestApps.Core.

Guidelines

• Use A2A when the remote system is an AI agent that reasons independently.
• Use MCP when the remote system is exposing tools or resources rather than a full agent.
• Add the A2A client to discover remote agents and invoke their skills.
• Treat A2A host registration and endpoint mapping as application-specific work.
• Configure authentication explicitly when implementing a host.

Client Registration

builder.Services.AddCrestAppsCore(crestApps => crestApps
    .AddAISuite(ai => ai
        .AddOpenAI()
        .AddA2AClient()
    )
);

Sample Host Endpoints and Options

The MVC and Blazor sample hosts implement their own internal host registrations. They publish agent cards at /.well-known/agent-card.json and map the A2A protocol endpoint at a2a, with an application-defined task manager and authorization policy. Those registrations and routes are not a public CrestApps.Core host-composition API.

Configure the shared host options in the application that implements those endpoints:

builder.Services.Configure<A2AHostOptions>(options =>
{
    options.AuthenticationType = A2AHostAuthenticationType.ApiKey;
    options.ApiKey = "your-secret-key";
});

A2AHostOptions also controls RequireAccessPermission for OpenID authentication and ExposeAgentsAsSkill for combined agent cards. Custom hosts must supply their own protocol route mapping, authentication, authorization, and task processing.

A2A vs MCP