using Microsoft.Extensions.AI; using Microsoft.Extensions.DependencyInjection; using ModelContextProtocol.Client; using ModelContextProtocol.Protocol; using System.Reflection; using System.Text.Json; namespace ModelContextProtocol.Server; /// /// Represents an invocable prompt used by Model Context Protocol clients and servers. /// /// /// /// is an abstract base class that represents an MCP prompt for use in the server (as opposed /// to , which provides the protocol representation of a prompt, and , which /// provides a client-side representation of a prompt). Instances of can be added into a /// to be picked up automatically when is used to create /// an , or added into a . /// /// /// Most commonly, instances are created using the static methods. /// These methods enable creating an for a method, specified via a or /// , and are what are used implicitly by WithPromptsFromAssembly and WithPrompts. The methods /// create instances capable of working with a large variety of .NET method signatures, automatically handling /// how parameters are marshaled into the method from the JSON received from the MCP client, and how the return value is marshaled back /// into the that's then serialized and sent back to the client. /// /// /// By default, parameters are sourced from the dictionary, which is a collection /// of key/value pairs. Those parameters are deserialized from the /// values in that collection. There are a few exceptions to this: /// /// /// /// parameters are automatically bound to a provided by the /// and that respects any s sent by the client for this operation's /// . /// /// /// /// /// parameters are bound from the for this request. /// /// /// /// /// parameters are bound directly to the instance associated /// with this request's . Such parameters may be used to understand /// what server is being used to process the request, and to interact with the client issuing the request to that server. /// /// /// /// /// parameters accepting values /// are bound to an instance manufactured to forward progress notifications /// from the prompt to the client. If the client included a in their request, progress reports issued /// to this instance will propagate to the client as notifications with /// that token. If the client did not include a , the instance will ignore any progress reports issued to it. /// /// /// /// /// When the is constructed, it may be passed an via /// . Any parameter that can be satisfied by that /// according to will be resolved from the provided to /// rather than from the argument collection. /// /// /// /// /// Any parameter attributed with will similarly be resolved from the /// provided to rather than from the argument collection. /// /// /// /// /// /// All other parameters are deserialized from the s in the dictionary. /// /// /// In general, the data supplied via the 's dictionary is passed along from the caller and /// should thus be considered unvalidated and untrusted. To provide validated and trusted data to the invocation of the prompt, consider having /// the prompt be an instance method, referring to data stored in the instance, or using an instance or parameters resolved from the /// to provide data to the method. /// /// /// Return values from a method are used to create the that is sent back to the client: /// /// /// /// /// Converted to a list containing a single with its set to contain the . /// /// /// /// Converted to a list containing the single . /// /// /// of /// Converted to a list containing all of the returned instances. /// /// /// /// Converted to a list of instances derived from the with . /// /// /// of /// Converted to a list of instances derived from all of the instances with . /// /// /// /// Returned directly without modification. /// /// /// /// Other returned types will result in an being thrown. /// /// public abstract class McpServerPrompt : IMcpServerPrimitive { /// Initializes a new instance of the class. protected McpServerPrompt() { } /// Gets the protocol type for this instance. /// /// The ProtocolPrompt property represents the underlying prompt definition as defined in the /// Model Context Protocol specification. It contains metadata like the prompt's name, /// description, and acceptable arguments. /// public abstract Prompt ProtocolPrompt { get; } /// /// Gets the metadata for this prompt instance. /// /// /// Contains attributes from the associated MethodInfo and declaring class (if any), /// with class-level attributes appearing before method-level attributes. /// public abstract IReadOnlyList Metadata { get; } /// /// Gets the prompt, rendering it with the provided request parameters and returning the prompt result. /// /// /// The request context containing information about the prompt invocation, including any arguments /// passed to the prompt. This object provides access to both the request parameters and the server context. /// /// /// The to monitor for cancellation requests. The default is . /// /// /// A representing the asynchronous operation, containing a with /// the prompt content and messages. /// /// is . /// The prompt implementation returns or an unsupported result type. public abstract ValueTask GetAsync( RequestContext request, CancellationToken cancellationToken = default); /// /// Creates an instance for a method, specified via a instance. /// /// The method to be represented via the created . /// Optional options used in the creation of the to control its behavior. /// The created for invoking . /// is . public static McpServerPrompt Create( Delegate method, McpServerPromptCreateOptions? options = null) => AIFunctionMcpServerPrompt.Create(method, options); /// /// Creates an instance for a method, specified via a instance. /// /// The method to be represented via the created . /// The instance if is an instance method; otherwise, . /// Optional options used in the creation of the to control its behavior. /// The created for invoking . /// is . /// is an instance method but is . public static McpServerPrompt Create( MethodInfo method, object? target = null, McpServerPromptCreateOptions? options = null) => AIFunctionMcpServerPrompt.Create(method, target, options); /// /// Creates an instance for a method, specified via an for /// and instance method, along with a representing the type of the target object to /// instantiate each time the method is invoked. /// /// The instance method to be represented via the created . /// /// Callback used on each function invocation to create an instance of the type on which the instance method /// will be invoked. If the returned instance is or , it will /// be disposed of after method completes its invocation. /// /// Optional options used in the creation of the to control its behavior. /// The created for invoking . /// is . public static McpServerPrompt Create( MethodInfo method, Func, object> createTargetFunc, McpServerPromptCreateOptions? options = null) => AIFunctionMcpServerPrompt.Create(method, createTargetFunc, options); /// Creates an that wraps the specified . /// The function to wrap. /// Optional options used in the creation of the to control its behavior. /// is . /// /// Unlike the other overloads of Create, the created by /// does not provide all of the special parameter handling for MCP-specific concepts, like . /// public static McpServerPrompt Create( AIFunction function, McpServerPromptCreateOptions? options = null) => AIFunctionMcpServerPrompt.Create(function, options); /// public override string ToString() => ProtocolPrompt.Name; /// string IMcpServerPrimitive.Id => ProtocolPrompt.Name; }