MCPServer Component

Properties Methods Events Config Settings Errors

Implements an easy way to expose custom tools, prompts, and resources to Model Context Protocol (MCP) clients.

Syntax

MCPSDK.MCPServer

Remarks

The MCPServer component provides a simple, event-driven API for interacting with clients that use the Model Context Protocol (MCP).

Supported Transport Mechanisms

The MCPServer component supports multiple transport mechanisms that are used to facilitate communication, which can be specified by setting the Transport property.

For local communication scenarios, such as when the server is launched as a subprocess of a client application, the component is capable of communicating via standard input and output streams. This setup is simple and enables direct data exchange between the client and server within the same process environment.

In remote deployment scenarios, where the server must be accessible to multiple concurrent clients across a network, the component also supports HTTP as the transport layer, using standard HTTP requests and responses for communication. To accommodate different hosting needs, the component includes a built-in embedded HTTP server, but it can also be integrated into an existing web infrastructure such as ASP.NET Core, Apache Tomcat, or other frameworks.

While the developer experience is largely the same between these, there are some differences in authentication and request processing depending on how the server is hosted. Comprehensive information on these hosting options and configuration can be found in the Hosting Options page.

Key Features

The MCPServer component supports all major MCP functionality, including tools, prompts, resources, and sampling.

Tools

Tools provide an opportunity for LLM clients to execute custom code, interact with external systems, and access dynamic or external data. Anything for which a function can be written can also be exposed as a tool. Common examples include database queries, file operations, or computations.

Registering Tools

Tools must be registered with the server via the RegisterTool method to be exposed to the client. Each registration requires a unique Name and a natural language Description. The name identifies the tool, while the description helps LLM clients determine when to use it. Since tool selection is client-driven, writing clear and specific descriptions is key to improving tool usage accuracy.

A tool may have zero or more associated parameters. Each parameter must be registered before the tool it will be associated with. Each parameter requires a Name and a Required boolean indicating if that parameter is required.

server.RegisterToolParam("limit", false); server.RegisterTool("random-num", "Generates a random number");

Handling Tool Invocations

Once a tool is registered, the client may invoke it at any time. When this occurs, the ToolRequest event is fired. This event includes the Name of the requested tool, which the server can use to determine how to respond. If the tool requires input, the server can retrieve parameters from the client using the GetToolParamValue method.

If the tool completes successfully and needs to return output, the server may respond using the AddToolMessage method. If an error occurs, such as an unrecognized tool is requested or a failure occurs during execution, the server should set the IsError parameter to true to inform the client that the request failed.

server.OnToolRequest += (s, e) => { if (e.Name == "random-num") { server.AddToolMessage((int)TToolMessageTypes.mtText, randomNum); } else { e.IsError = true; } };

Prompts

Prompts are predefined conversation starters or instructions that can be quickly inserted into the LLM's context to guide specific interactions or workflows. Prompts serve as standardized templates for common conversational patterns and allow for consistent responses for tasks like reviewing code, analyzing data, or answering specific types of questions. Prompts may also include arguments that allow runtime customization.

Unlike tools, prompts are user-driven. The client does not select prompts on its own; instead, the user chooses when and which prompt to insert, which allows for consistent and reusable guidance tailored to specific workflows.

Registering Prompts

Prompts must be registered with the server via the RegisterPrompt method to be exposed to the client. Each registration requires a unique Name and a natural language Description. The name identifies the prompt, while the description helps the user understand its purpose. Once registered, the prompt becomes available for the end user to insert into the client context as needed.

A prompt may have zero or more associated arguments. Each argument must be registered before the prompt it will be associated with. Each argument requires a Name and a Required boolean indicating if that argument is required.

// Define argument schema. server.RegisterPromptArg("code", true); server.RegisterPromptArg("language", false); // Register the prompt. string name = "explain-code"; string description = "Explain how code works"; server.RegisterPrompt(name, description);

Handling Prompt Requests

When a user selects a prompt, the client notifies the server, causing the PromptRequest event to be fired. This event includes the Name of the requested prompt, allowing the server to determine the correct response to be sent using the AddPromptMessage method. Any related prompt arguments may also be retrieved by their associated name using the GetPromptParamValue method.

server.OnPromptRequest += (s, e) => { // Retrieve runtime values sent by client. string code = server.GetPromptParamValue("code"); string language = server.GetPromptParamValue("language") ?? "Unknown"; // Build response messages. // Assuming the client sent 'a = 1 + 2;' for the 'code' argument, and 'python' for the 'language' argument. server.AddPromptMessage((int)TRoles.rtAssistant, "Don't add comments."); server.AddPromptMessage((int)TRoles.rtUser, $"Explain how this {language} code works:\n\n{code}"); };

Resources

Resources provide persistent, read-only content that can be requested once by the user and reused throughout the session. These are typically static files such as documentation, source code, or other reference materials that help provide context for LLM interactions.

Registering Resources

Resources must be registered with the server via the RegisterResource method to be exposed to the client. Each registration requires a unique Uri, a short display Name, and a natural language Description.

server.RegisterResource("file://server.cs", "Server Demo", "The source code for a simple MCP SDK Server Demo");

Handling Resource Requests

When a user requests a resource, the ResourceRequest event is fired. This event includes the Uri of the requested resource, allowing the server to locate and load the correct resource using the AddResourceContent method. The client will manage the resource afterward, making it available for reuse as needed.

server.OnResourceRequest += (s, e) => { string fileName = e.Uri.Substring("file://".Length); if (File.Exists(fileName)) { string content = File.ReadAllText(fileName); server.AddResourceContent(e.Uri, content, "text/plain"); } };

Property List

The following is the full list of the properties of the component with short descriptions. Click on the links for further details.


Listening	Whether the component is listening for incoming connections.
ProcessingMode	The mode in which the component will be hosted.
Prompts	A collection of registered prompts.
RegisteredPromptArgs	A collection of prompt arguments to be registered.
RegisteredToolParams	A collection of tool parameters to be registered.
Request	The body of the HTTP request to be processed by the component.
RequestHeaders	The full set of headers of the HTTP request to be processed by the component.
Resources	A collection of registered resources.
Response	The body of the HTTP response generated after processing a request with the component.
ResponseHeaders	The full set of headers of the HTTP response generated after processing a request with the component.
SamplingMessages	A collection of messages to send when requesting language model generation from the client.
ServerCert	The certificate used during SSL negotiation.
ServerSettings	The embedded HTTP server settings used by the component.
SystemPrompt	An instruction sent to the client's language model to influence its behavior during a sampling request.
Tools	A collection of registered tools.
Transport	The transport mechanism used for communication.

Method List

The following is the full list of the methods of the component with short descriptions. Click on the links for further details.


addPromptMessage	Adds a prompt message to be returned during a prompt request.
addResourceContent	Adds data to be returned during a resource request.
addToolMessage	Adds a tool message to be returned during a tool request.
config	Sets or retrieves a configuration setting.
doEvents	Processes events from the internal queue.
getPromptParamValue	Retrieves the value of an existing prompt parameter.
getToolParamValue	Retrieves the value of an existing tool parameter.
processRequest	Processes the request and sends the result.
registerPrompt	Registers a prompt that can be requested by the client.
registerPromptArg	Registers an argument for a prompt.
registerResource	Registers a resource that can be requested by the client.
registerTool	Registers a tool that can be requested by the client.
registerToolParam	Registers a parameter for a tool.
sendSamplingRequest	Requests language model reasoning from the client.
startListening	Instructs the component to start listening for incoming connections.
stopListening	Instructs the component to stop listening for new connections.
unregisterPrompt	Unregisters an existing prompt.
unregisterResource	Unregisters an existing resource.
unregisterTool	Unregisters an existing tool.

Event List

The following is the full list of the events fired by the component with short descriptions. Click on the links for further details.


Error	Fires when an error occurs during operation.
Log	Fires once for each log message.
PromptRequest	Fires when a prompt is requested by the client.
ResourceRequest	Fires when a resource is requested by the client.
SessionEnd	Fires when the component ends a session.
SessionStart	Fires when the component starts a session.
ToolRequest	Fires when a tool is requested by the client.

Config Settings

The following is a list of config settings for the component with short descriptions. Click on the links for further details.


LogLevel	Specifies the level of detail that is logged.
MaxTokens	Specifies the maximum number of tokens to generate when sampling the client's LLM.
PageSizePrompts	Specifies the page size to use when responding to prompt listing requests from the client.
PageSizeResources	Specifies the page size to use when responding to resource listing requests from the client.
PageSizeTools	Specifies the page size to use when responding to tool listing requests from the client.
BuildInfo	Information about the product's build.
GUIAvailable	Whether or not a message loop is available for processing events.
LicenseInfo	Information about the current license.
MaskSensitiveData	Whether sensitive data is masked in log messages.
UseDaemonThreads	Whether threads created by the component are daemon threads.
UseInternalSecurityAPI	Whether or not to use the system security libraries or an internal implementation.

Listening Property (MCPServer Component)

Whether the component is listening for incoming connections.

Syntax

public boolean isListening();

Default Value

False

Remarks

When the Transport property is set to ttStdio, or it is set to ttHTTP and the ProcessingMode property is set to modeEmbeddedServer, this property indicates whether the component is listening for connections on the port specified by the LocalPort property.

The StartListening and StopListening methods can be used to control whether the component is listening.

This property is read-only.

ProcessingMode Property (MCPServer Component)

The mode in which the component will be hosted.

Syntax

public int getProcessingMode();
public void setProcessingMode(int processingMode);
Enumerated values:
  public final static int modeEmbeddedServer = 0;

  public final static int modeExternalServer = 1;

  public final static int modeOffline = 2;

Default Value

Remarks

When the Transport property is set to ttHTTP, this property governs whether the component operates via the embedded HTTP server, an external server, or in a fully-offline mode. Possible values are as follows:

modeEmbeddedServer (0, default): Uses the embedded server.
modeExternalServer (1): Uses an external server framework.
modeOffline (2): Uses offline processing.

Please refer to the Hosting Options pages to learn more about the different processing modes and how they relate to configuring a host server.

Prompts Property (MCPServer Component)

A collection of registered prompts.

Syntax

public PromptList getPrompts();

Remarks

This collection holds a list of Prompt items.

Calling the RegisterPrompt and UnregisterPrompt methods will add and remove items to and from this collection, respectively.

This property is read-only and not available at design time.

Please refer to the Prompt type for a complete list of fields.

RegisteredPromptArgs Property (MCPServer Component)

A collection of prompt arguments to be registered.

Syntax

public PromptArgList getRegisteredPromptArgs();

Remarks

This collection holds a list of PromptArg items to be registered.

Calling the RegisterPromptArg method will add items to this collection, and calling the RegisterPrompt method will clear this collection.

Example: // Register two prompt argument schemas. server.RegisterPromptArg("code", "Code to explain", true); server.RegisterPromptArg("language", "Programming language", false); // Register the prompt with the added arguments. server.RegisterPrompt("explain-code", "Explain how code works");

This property is not available at design time.

Please refer to the PromptArg type for a complete list of fields.

RegisteredToolParams Property (MCPServer Component)

A collection of tool parameters to be registered.

Syntax

public ToolParamList getRegisteredToolParams();

Remarks

This collection holds a list of ToolParam items to be registered.

Calling the RegisterToolParam method will add items to this collection, and calling the RegisterTool method will clear this collection.

This property is not available at design time.

Please refer to the ToolParam type for a complete list of fields.

Request Property (MCPServer Component)

The body of the HTTP request to be processed by the component.

Syntax

public byte[] getRequest();
public void setRequest(byte[] request);

Default Value

Remarks

When the Transport property is set to ttHTTP and the ProcessingMode property is set to modeOffline, the component processes inbound HTTP requests via this property and the RequestHeaders property.

After setting this property to the full body content of the HTTP request, as well as setting any headers in the RequestHeaders property, the component will begin processing the request when the ProcessRequest method is called.

RequestHeaders Property (MCPServer Component)

The full set of headers of the HTTP request to be processed by the component.

Syntax

public String getRequestHeaders();
public void setRequestHeaders(String requestHeaders);

Default Value

Remarks

When the Transport property is set to ttHTTP and the ProcessingMode property is set to modeOffline, the component processes inbound HTTP requests via this property and the Request property.

After setting this property to the header content of the HTTP request, as well as setting the body content in the Request property, the component will begin processing the request when the ProcessRequest method is called.

Resources Property (MCPServer Component)

A collection of registered resources.

Syntax

public ResourceList getResources();

Remarks

This collection holds a list of Resource items.

Calling the RegisterResource and UnregisterResource methods will add and remove items to and from this collection, respectively.

This property is read-only and not available at design time.

Please refer to the Resource type for a complete list of fields.

Response Property (MCPServer Component)

The body of the HTTP response generated after processing a request with the component.

Syntax

public byte[] getResponse();
public void setResponse(byte[] response);

Default Value

Remarks

When the Transport property is set to ttHTTP and the ProcessingMode property is set to modeOffline, this property holds the body of the HTTP response that was generated as a result of calling the ProcessRequest method.

Note that this response is not sent to a client, and instead the component simply populates this property along with the ResponseHeaders property.

ResponseHeaders Property (MCPServer Component)

The full set of headers of the HTTP response generated after processing a request with the component.

Syntax

public String getResponseHeaders();
public void setResponseHeaders(String responseHeaders);

Default Value

Remarks

When the Transport property is set to ttHTTP and the ProcessingMode property is set to modeOffline, this property holds the headers of the HTTP response that was generated as a result of calling the ProcessRequest method.

Note that this response is not sent to a client, and instead the component simply populates this property along with the Response property.

SamplingMessages Property (MCPServer Component)

A collection of messages to send when requesting language model generation from the client.

Syntax

public SamplingMessageList getSamplingMessages();

Remarks

This collection holds a list of SamplingMessage items.

When the Transport property is set to ttStdio, calling the SendSamplingRequest method sends the messages currently in this collection to the client, where they will be passed into the client's language model as input for text generation.

This property is not available at design time.

Please refer to the SamplingMessage type for a complete list of fields.

ServerCert Property (MCPServer Component)

The certificate used during SSL negotiation.

Syntax

public Certificate getServerCert();
public void setServerCert(Certificate serverCert);

Remarks

When the Transport property is set to ttHTTP and the ProcessingMode property is set to modeEmbeddedServer, this property holds the digital certificate that the component will use during SSL negotiation.

This is the server's certificate, and it must be set before the StartListening method is called.

Please refer to the Certificate type for a complete list of fields.

ServerSettings Property (MCPServer Component)

The embedded HTTP server settings used by the component.

Syntax

public ServerSettings getServerSettings();
public void setServerSettings(ServerSettings serverSettings);

Remarks

When the Transport property is set to ttHTTP and the ProcessingMode property is set to modeEmbeddedServer, this property is used to define the necessary fields to configure the embedded HTTP server.

Please refer to the ServerSettings type for a complete list of fields.

SystemPrompt Property (MCPServer Component)

An instruction sent to the client's language model to influence its behavior during a sampling request.

Syntax

public String getSystemPrompt();
public void setSystemPrompt(String systemPrompt);

Default Value

Remarks

When the Transport property is set to ttStdio, this property specifies an instruction sent to the client's language model to influence its behavior when the SendSamplingRequest method is called. It acts as high-level guidance or context for how the language model should interpret and respond to the messages in the SamplingMessages collection.

Example: server.SystemPrompt = "You are an assistant meant to summarize text only using a formal tone."; SamplingMessage message = new SamplingMessage(); message.Role = TRoles.rtUser; message.Text = "Summarize the following text: " + text; server.SamplingMessages.Add(message); string result = server.SendSamplingRequest();

Tools Property (MCPServer Component)

A collection of registered tools.

Syntax

public ToolList getTools();

Remarks

This collection holds a list of Tool items.

Calling the RegisterTool and UnregisterTool methods will add and remove items to and from this collection, respectively.

This property is read-only and not available at design time.

Please refer to the Tool type for a complete list of fields.

Transport Property (MCPServer Component)

The transport mechanism used for communication.

Syntax

public int getTransport();
public void setTransport(int transport);
Enumerated values:
  public final static int ttStdio = 1;

  public final static int ttHTTP = 2;

Default Value

Remarks

This property indicates whether the component operates via the standard input/output or HTTP transport mechanism. Possible values are as follows:

ttStdio (1, default): Enables communication through standard input and output streams, but the component is limited to serving a single client at once due to the server acting as a subprocess of a client application.
ttHTTP (2): Enables communication via HTTP requests and responses, and allows the component to serve multiple clients at once.

This property is not available at design time.

AddPromptMessage Method (MCPServer Component)

Adds a prompt message to be returned during a prompt request.

Syntax

public void addPromptMessage(int role, String text);

Remarks

This method is used to add a new prompt message to be passed back to the client during an ongoing prompt request. It may only be called from within the PromptRequest event.

Role determines the message's origin and context within the conversation flow. Valid roles include:


`0 (rtUser)`	Message from the end user requesting assistance.
`1 (rtAssistant)`	Message from the client providing responses.

Text contains natural language describing the prompt that will be passed into the client's language model (e.g., Review python code, Summarize an article, or Provide an example of using the /n software MCP SDK).

Example: server.OnPromptRequest += (s, e) => { if (e.Name.Equals("Greeting")) { server.AddPromptMessage((int)TRoles.rtUser, "Hello!"); } };

Advanced Example: server.OnPromptRequest += (s, e) => { if (e.Name.Equals("Code Review")) { string code = server.GetPromptParamValue("code"); string language = server.GetPromptParamValue("language"); string reviewType = server.GetPromptParamValue("reviewType"); string instructions = "Please review the following " + language + " code."; if (!string.IsNullOrEmpty(reviewType)) { instructions += " focusing on " + reviewType; } instructions += ":"; server.AddPromptMessage((int)TRoles.rtUser, instructions); server.AddPromptMessage((int)TRoles.rtUser, code); } };

AddResourceContent Method (MCPServer Component)

Adds data to be returned during a resource request.

Syntax

public void addResourceContent(String uri, String text, String mimeType);

Remarks

This method is used to add resource content to be passed back to the client during an ongoing resource request, providing the actual data that clients are requesting when they access a specific resource. It may only be called from within the ResourceRequest event and may be called multiple times during the same resource request to provide multiple related resources or different versions of the same content.

Uri specifies the unique resource identifier that corresponds to the content being provided.

Text contains text data that will be included in the response for the ongoing resource request.

MimeType (e.g., text/plain or application/json) informs the client of how the data passed into Text should be interpreted and processed.

Example: server.OnResourceRequest += (s, e) => { string uri = e.Uri.ToString(); if (uri.StartsWith("file:///")) { string fileName = uri.Substring("file:///".Length).Replace('/', Path.DirectorySeparatorChar); string fullPath = Path.Combine(baseDir, fileName); if (File.Exists(fullPath)) { string data = File.ReadAllText(fullPath); server.AddResourceContent(uri, data, "text/plain"); } } };

Advanced Example server.OnResourceRequest += (s, e) => { string uri = e.Uri.ToString(); if (uri.StartsWith("file:///")) { string fileName = uri.Substring("file:///".Length).Replace('/', Path.DirectorySeparatorChar); string fullPath = Path.Combine(baseDir, fileName); string fileExtension = Path.GetExtension(fullPath).ToLower(); string mimeType = GetMimeType(fileExtension); if (IsImageFile(fileExtension)) { // Handle image files. byte[] imageBytes = File.ReadAllBytes(fullPath); string base64Image = Convert.ToBase64String(imageBytes); server.AddResourceContent(uri, base64Image, mimeType); } else { // Handle text files. string data = File.ReadAllText(fullPath); server.AddResourceContent(uri, data, mimeType); } } };

AddToolMessage Method (MCPServer Component)

Adds a tool message to be returned during a tool request.

Syntax

public void addToolMessage(int type, String value);

Remarks

This method is used to add a new tool message to be passed back to the client during an ongoing tool request. It may only be called from within the ToolRequest event, and should only be called once per each type of data to be returned.

Type identifies the data type of the message being added. Valid data types include:


`0 (mtText)`	Natural language text data.
`1 (mtAudio)`	A base64-encoded string representing audio data (e.g., MP3 or WAV).
`2 (mtImage)`	A base64-encoded string representing image data (e.g., PNG or JPEG).
`3 (mtResource)`	A string message representing the contents of a text-based resource (e.g., `file://logs/output.txt`).

Value contains text that will be included in the response for the ongoing tool request.

Config Method (MCPServer Component)

Sets or retrieves a configuration setting.

Syntax

public String config(String configurationString);

Remarks

Config is a generic method available in every component. It is used to set and retrieve configuration settings for the component.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, access to these internal properties is provided through the Config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

DoEvents Method (MCPServer Component)

Processes events from the internal queue.

Syntax

public void doEvents();

Remarks

This method causes the component to process any available events. If no events are available, it waits for a preset period of time and then returns.

GetPromptParamValue Method (MCPServer Component)

Retrieves the value of an existing prompt parameter.

Syntax

public String getPromptParamValue(String name);

Remarks

This method is used to retrieve the value of an existing prompt parameter. It may only be called from within the PromptRequest event.

Name contains a unique identifier for the prompt parameter that is being retrieved. This must match the value passed into the RegisterPromptArg method when the parameter was registered.

The value associated with the prompt parameter is returned when calling this method. If the specified parameter does not exist or was not provided by the client, then an empty string is returned.

Example: // Define argument schema. server.RegisterPromptArg("code", "Code to explain", true); server.RegisterPromptArg("language", "Programming language", false); // Register the prompt. string name = "explain-code"; string description = "Explain how code works"; server.RegisterPrompt(name, description); // Handling the prompt request. server.OnPromptRequest += (s, e) => { // Retrieve runtime values sent by client. string code = server.GetPromptParamValue("code"); string language = server.GetPromptParamValue("language") ?? "Unknown"; // Build response messages. // Assuming the client sent 'a = 1 + 2;' for the 'code' argument, and 'python' for the 'language' argument. // The following response should contain a user message with the text 'Explain how this python code works: \n\na = 1 + 2;'. server.AddPromptMessage("user", $"Explain how this {language} code works:\n\n{code}"); };

GetToolParamValue Method (MCPServer Component)

Retrieves the value of an existing tool parameter.

Syntax

public String getToolParamValue(String name);

Remarks

This method is used to retrieve the value of an existing tool parameter. It may only be called from within the ToolRequest event.

Name contains a unique identifier for the tool parameter that is being retrieved. This must match the value passed into the RegisterToolParam method when the parameter was registered.

The value associated with the tool parameter is returned when calling this method. If the specified parameter does not exist or was not provided by the client, then an empty string is returned.

ProcessRequest Method (MCPServer Component)

Processes the request and sends the result.

Syntax

public void processRequest(Object request, Object response);

Remarks

When the Transport property is set to ttHTTP and the ProcessingMode property is set to modeExternalServer or modeOffline, this method acts as the main entry point for the component and is used to process a specific request. This method should not be called when the component is running in the modeEmbeddedServer mode.

Note that when using the modeOffline mode, the component processes the request and its associated headers supplied via the Request and RequestHeaders properties, respectively, and therefore ignores the parameters of this method.

When using the modeExternalServer mode, Request and Response must be set to instances of the HttpServletRequest and HttpServletResponse classes that correspond to the request to be handled and response to be constructed, respectively.

Note that authentication occurs fully outside the scope of the component, and the logic that verifies these credentials is separate from any interaction with the component. Only once the request has been authenticated through this external verification should the Request be passed to this method.

RegisterPrompt Method (MCPServer Component)

Registers a prompt that can be requested by the client.

Syntax

public void registerPrompt(String name, String description);

Remarks

This method is used to register a new prompt that can be requested by the client.

Name specifies the unique name identifier for the prompt.

Description is critical in helping the client to understand the purpose and functionality of the prompt and should be set to a brief, human-readable description of what the prompt does.

Any prompt arguments associated with the prompt to be registered must be registered via the RegisterPromptArg method before this method is called.

Once the prompt has been registered, it is added to the Prompts collection and may be requested by the client, causing the PromptRequest event to be fired. Additionally, the RegisteredPromptArgs collection is cleared, and all prompt arguments previously in the collection are applied to the prompt.

RegisterPromptArg Method (MCPServer Component)

Registers an argument for a prompt.

Syntax

public void registerPromptArg(String name, String description, boolean required);

Remarks

This method is used to register a new argument for a prompt that has not yet been registered via the RegisterPrompt method.

Name specifies the unique name identifier for the prompt argument.

Description identifies what information should be provided to this argument.

Required specifies whether the prompt argument must be supplied by the client when requesting the prompt.

Once the prompt argument has been registered, it is added to the RegisteredPromptArgs collection. All of the prompt arguments in this collection will be applied to the next prompt registered via RegisterPrompt, after which the collection is cleared.

RegisterResource Method (MCPServer Component)

Registers a resource that can be requested by the client.

Syntax

public void registerResource(String uri, String name, String description);

Remarks

This method is used to register a new resource that can be requested by the client.

Uri specifies the unique identifier for the resource, of which common formats include file:///filename.ext for files, standard HTTP/HTTPS URLs for web resources, or custom schemes like db://table_name.

Name indicates the display name of the resource shown to end users by the client.

Description should be set to a brief, human-readable description of the resource's purpose, its content type, and appropriate use cases.

Once the resource has been registered, it is added to the Resources collection and may be requested by the client, causing the ResourceRequest event to be fired.

Note that once registered, resources become available for discovery, but the actual content (including format details and MIME type) is not loaded until a specific resource has been requested.

Resource URIs

Resource URIs represent a unique identifier for a resource and must follow the format: [scheme]://[host]/[path]

Common schemes include:


file://:	For local or file-like resources, even if they do not map directly to a local file (e.g., `file:///example.png`).
https://:	Refers to web-accessible resources. This should only be used if the clients can fetch and parse the content directly (e.g., `https://www.nsoftware.com`).
git://:	Indicates resources that originate from a Git repository (e.g., `git://github.com/nsoftware/repo.git`).

Custom URI Schemes

In addition to the previously listed schemes, applications may define their own custom URI schemes. These must be in accordance with RFC3986, especially with regards to reserved characters and general formatting recommendations. Characters such as :, /, and ? must be percent-encoded when used as data.

Client behavior may vary; therefore when registering resource URIs, servers must be prepared to handle every resource they register, regardless of client behavior. MCP-compatible clients may ignore scheme recommendations or fail to fetch resources as expected.

RegisterTool Method (MCPServer Component)

Registers a tool that can be requested by the client.

Syntax

public void registerTool(String name, String description);

Remarks

This method is used to register a new tool that can be requested by the client.

Name specifies the unique name identifier for the tool.

Description is critical in helping the client to understand when to invoke this tool should be set to a brief, human-readable description of what the tool does.

Any tool parameters associated with the tool to be registered must be registered via the RegisterToolParam method before this method is called.

Once the tool has been registered, it is added to the Tools collection and may be requested by the client, causing the ToolRequest event to be fired. Additionally, the RegisteredToolParams collection is cleared, and all tool parameters previously in the collection are applied to the tool.

RegisterToolParam Method (MCPServer Component)

Registers a parameter for a tool.

Syntax

public void registerToolParam(String name, boolean required);

Remarks

This method is used to register a new parameter for a tool that has not yet been registered via the RegisterTool method.

Name specifies the unique name identifier for the tool parameter.

Required specifies whether the tool parameter must be supplied by the client when requesting the tool.

Once the tool parameter has been registered, it is added to the RegisteredToolParams collection. All of the tool parameters in this collection will be applied to the next tool registered via RegisterTool, after which the collection is cleared.

SendSamplingRequest Method (MCPServer Component)

Requests language model reasoning from the client.

Syntax

public String sendSamplingRequest();

Remarks

When the Transport property is set to ttStdio, this method is used to send a sampling request to the client, which is often used in order to utilize language model reasoning.

When called, the set of messages in the SamplingMessages collection will be passed over to the client in order for them to be used as a prompt for the client's language model. This method will then return the output of the prompt as text.

Example: server.OnToolRequest += (s, e) => { if (e.Name.Contains("summarize-text")) { // Grab text to summarize from the corresponding tool parameter. string text = GetText(); // Custom logic. // Add a prompt asking the client's LLM to summarize the text we just received. SamplingMessage message = new SamplingMessage(); message.Role = TRoles.rtUser; message.Text = "Summarize the following text: " + text; server.SamplingMessages.Add(message); // Send the sampling messages over to the client and request a response. string result = server.SendSamplingRequest(); // Return some text. server.AddToolMessage((int)TToolMessageTypes.mtText, result); } };

System Prompts

When performing a sampling request, the server may specify a system prompt to influence the client's LLM behavior during sampling. A system prompt provides high-level guidance or context for how the language model should interpret and respond to the messages in SamplingMessages. It is especially useful for establishing tone, role, or task-specific instructions.

StartListening Method (MCPServer Component)

Instructs the component to start listening for incoming connections.

Syntax

public void startListening();

Remarks

When the Transport property is set to ttStdio, or it is set to ttHTTP and the ProcessingMode property is set to modeEmbeddedServer, this method instructs the component to start listening for incoming connections on the port specified by LocalPort.

To stop listening for new connections, please refer to the StopListening method.

StopListening Method (MCPServer Component)

Instructs the component to stop listening for new connections.

Syntax

public void stopListening();

Remarks

When the Transport property is set to ttStdio, or it is set to ttHTTP and the ProcessingMode property is set to modeEmbeddedServer, this method instructs the component to stop listening for new connections. After being called, any new connection attempts will be rejected. Calling this method does not disconnect existing connections.

UnregisterPrompt Method (MCPServer Component)

Unregisters an existing prompt.

Syntax

public void unregisterPrompt(String name);

Remarks

This method is used to unregister a prompt that had previously been registered via the RegisterPrompt method. Once called, the specified prompt will be removed from the Prompts collection and will not be able to be requested by the client until it is registered again with RegisterPrompt.

Name specifies the unique name identifier for the prompt that will be unregistered. This should match the value passed into RegisterPrompt when the prompt was registered.

Example: // Register a prompt, making it available for clients to request. server.RegisterPromptArg("code-to-review", "The source code to review", true); server.RegisterPrompt("review-code", "Review the specified code"); // Handle client requests. // Unregister the prompt and prevent clients from being able to request it. server.UnregisterPrompt("review-code");

UnregisterResource Method (MCPServer Component)

Unregisters an existing resource.

Syntax

public void unregisterResource(String uri);

Remarks

This method is used to unregister a resource that had previously been registered via the RegisterResource method. Once called, the specified resource will be removed from the Resources collection and will not be able to be requested by the client until it is registered again with RegisterResource.

Uri specifies the unique identifier for the resource that will be unregistered. This should match the value passed into RegisterResource when the resource was registered.

Example: // Register a resource, making it available for clients to request. server.RegisterResource("file:///kb/test.txt", "Sample resource file", "A sample resource file with text content"); // Handle client requests. // Unregister the resource and prevent clients from being able to request it. server.UnregisterResource("file:///kb/test.txt");

Resource URIs

Resource URIs represent a unique identifier for a resource and must follow the format: [scheme]://[host]/[path]

Common schemes include:


file://:	For local or file-like resources, even if they do not map directly to a local file (e.g., `file:///example.png`).
https://:	Refers to web-accessible resources. This should only be used if the clients can fetch and parse the content directly (e.g., `https://www.nsoftware.com`).
git://:	Indicates resources that originate from a Git repository (e.g., `git://github.com/nsoftware/repo.git`).

Custom URI Schemes

UnregisterTool Method (MCPServer Component)

Unregisters an existing tool.

Syntax

public void unregisterTool(String name);

Remarks

This method is used to unregister a tool that had previously been registered via the RegisterTool method. Once called, the specified tool will be removed from the Tools collection and will not be able to be invoked by the client until it is registered again with RegisterTool.

Name specifies the unique name identifier for the tool that will be unregistered. This should match the value passed into RegisterTool when the tool was registered.

Example: // Register a tool, making it available for clients to invoke. server.RegisterTool("random-num", "Generate a random number"); // Handle client requests. // Unregister the tool and prevent clients from being able to invoke it. server.UnregisterTool("random-num");

Error Event (MCPServer Component)

Fires when an error occurs during operation.

Syntax

public class DefaultMCPServerEventListener implements MCPServerEventListener {
  ...
  public void error(MCPServerErrorEvent e) {}
  ...
}

public class MCPServerErrorEvent {
  public String connectionId;

  public int errorCode;

  public String description;

}

Remarks

This event is fired when an unhandled exception is caught by the component, providing information about the error.

ConnectionId identifies the connection associated with the error.

ErrorCode contains the numeric error code representing the specific error condition.

Description contains a textual description of the error that occurred.

Log Event (MCPServer Component)

Fires once for each log message.

Syntax

public class DefaultMCPServerEventListener implements MCPServerEventListener {
  ...
  public void log(MCPServerLogEvent e) {}
  ...
}

public class MCPServerLogEvent {
  public int logLevel;

  public String message;

  public String logType;

}

Remarks

This event is fired once for each log message generated by the component. The verbosity is controlled by the LogLevel configuration.

LogLevel indicates the detail level of the message. Possible values are:


0 (None)	No messages are logged.
1 (Info - Default)	Informational events are logged.
2 (Verbose)	Detailed data is logged.
3 (Debug)	Debug data including all sent and received NFS operations are logged.

Message is the log message.

LogType identifies the type of log entry. Possible values are as follows:

PromptRequest Event (MCPServer Component)

Fires when a prompt is requested by the client.

Syntax

public class DefaultMCPServerEventListener implements MCPServerEventListener {
  ...
  public void promptRequest(MCPServerPromptRequestEvent e) {}
  ...
}

public class MCPServerPromptRequestEvent {
  public String name;

  public String description;

}

Remarks

This event is fired when a prompt has been requested by the client and allows the server to run custom logic. The text-based output to be returned to the client should be passed to the AddPromptMessage method while handling this event. This method may be called multiple times during the same prompt request to build a complete conversation history with alternating roles.

The GetPromptParamValue method may be called from within this event to retrieve the values for the prompt arguments associated with the requested prompt.

Name contains the unique name associated with the prompt.

Description holds the brief, human-readable description of what the prompt does.

ResourceRequest Event (MCPServer Component)

Fires when a resource is requested by the client.

Syntax

public class DefaultMCPServerEventListener implements MCPServerEventListener {
  ...
  public void resourceRequest(MCPServerResourceRequestEvent e) {}
  ...
}

public class MCPServerResourceRequestEvent {
  public String uri;

}

Remarks

This event is fired when a resource has been requested by the client and allows the server to run custom logic. The resource content to be returned to the client should be passed to the AddResourceContent method while handling this event. This method may be called multiple times during the same resource request to provide multiple related resources or different versions of the same content.

Uri specifies the unique resource identifier for the requested resource.

Example: server.OnResourceRequest += (s, e) => { string uri = e.Uri.ToString(); if (uri == "file:///logs/app.log") { string logData = File.ReadAllText("app.log"); server.AddResourceContent(uri, logData, "text/plain"); } else { server.Response = "[Unknown resource]"; } };

Resource URIs

Resource URIs represent a unique identifier for a resource and must follow the format: [scheme]://[host]/[path]

Common schemes include:


file://:	For local or file-like resources, even if they do not map directly to a local file (e.g., `file:///example.png`).
https://:	Refers to web-accessible resources. This should only be used if the clients can fetch and parse the content directly (e.g., `https://www.nsoftware.com`).
git://:	Indicates resources that originate from a Git repository (e.g., `git://github.com/nsoftware/repo.git`).

Custom URI Schemes

SessionEnd Event (MCPServer Component)

Fires when the component ends a session.

Syntax

public class DefaultMCPServerEventListener implements MCPServerEventListener {
  ...
  public void sessionEnd(MCPServerSessionEndEvent e) {}
  ...
}

public class MCPServerSessionEndEvent {
  public long sessionId;

}

Remarks

When the Transport property is set to ttHTTP, this event fires when the component ends a previously started session. The component doesn't expect any errors to occur or be reported by handlers of this event.

SessionId specifies the unique identifier for the current session and can be obtained from the initial SessionStart event when the session is first opened.

SessionStart Event (MCPServer Component)

Fires when the component starts a session.

Syntax

public class DefaultMCPServerEventListener implements MCPServerEventListener {
  ...
  public void sessionStart(MCPServerSessionStartEvent e) {}
  ...
}

public class MCPServerSessionStartEvent {
  public long sessionId;

  public int resultCode;

}

Remarks

When the Transport property is set to ttHTTP, this event fires when a new session with a connected client begins. The lifetime of a session is a single HTTP request and response, meaning once the response has been sent, the session ends.

SessionId is the unique identifier of the session, assigned by the component. It is provided as a parameter in all other events so that the operations for a particular client session may be tracked.

ResultCode provides an opportunity to report the operation as failed. This parameter will always be 0 when the event is fired, indicating the operation was successful. If the event cannot be handled in a "successful" manner for some reason, this must be set to a non-zero value.

Reporting an error will abort the operation.

ToolRequest Event (MCPServer Component)

Fires when a tool is requested by the client.

Syntax

public class DefaultMCPServerEventListener implements MCPServerEventListener {
  ...
  public void toolRequest(MCPServerToolRequestEvent e) {}
  ...
}

public class MCPServerToolRequestEvent {
  public int connectionId;

  public String name;

  public String description;

  public boolean isError;

}

Remarks

This event is fired when a tool has been requested by the client and allows the server to run custom logic. If applicable, the text-based output to be returned to the client should be passed to the AddToolMessage method while handling this event. This method may be called multiple times, once for each data type, if the tool needs to pass multiple types of data back to the client.

The GetToolParamValue method may be called from within this event to retrieve the values for the tool parameters associated with the requested tool.

Name identifies the unique name associated with the tool.

Description holds the brief, human-readable description of what the tool does, and while not necessary, is often used here for sampling.

IsError may be set to true to indicate when an error condition is met and the tool cannot be handled successfully.

Example: server.OnToolRequest += (s, e) => { if (e.Name.Contains("read-docs")) { // Execute custom logic. string documentation = ReadDocumentation(); // Return some text. server.AddToolMessage((int)TToolMessageTypes.mtText, documentation); } };

Certificate Type

This is the digital certificate being used.

Remarks

This type describes the current digital certificate. The certificate may be a public or private key. The fields are used to identify or select certificates.

The following fields are available:

Fields

EffectiveDate
String (read-only)
Default Value: ""

The date on which this certificate becomes valid. Before this date, it is not valid. The date is localized to the system's time zone. The following example illustrates the format of an encoded date:

23-Jan-2000 15:00:00.

ExpirationDate
String (read-only)
Default Value: ""

The date on which the certificate expires. After this date, the certificate will no longer be valid. The date is localized to the system's time zone. The following example illustrates the format of an encoded date:

23-Jan-2001 15:00:00.

ExtendedKeyUsage
String (read-only)
Default Value: ""

A comma-delimited list of extended key usage identifiers. These are the same as ASN.1 object identifiers (OIDs).

Fingerprint
String (read-only)
Default Value: ""

The hex-encoded, 16-byte MD5 fingerprint of the certificate. This property is primarily used for keys which do not have a corresponding X.509 public certificate, such as PEM keys that only contain a private key. It is commonly used for SSH keys.

The following example illustrates the format: bc:2a:72:af:fe:58:17:43:7a:5f:ba:5a:7c:90:f7:02

FingerprintSHA1
String (read-only)
Default Value: ""

The hex-encoded, 20-byte SHA-1 fingerprint of the certificate. This property is primarily used for keys which do not have a corresponding X.509 public certificate, such as PEM keys that only contain a private key. It is commonly used for SSH keys.

The following example illustrates the format: 30:7b:fa:38:65:83:ff:da:b4:4e:07:3f:17:b8:a4:ed:80:be:ff:84

FingerprintSHA256
String (read-only)
Default Value: ""

The hex-encoded, 32-byte SHA-256 fingerprint of the certificate. This property is primarily used for keys which do not have a corresponding X.509 public certificate, such as PEM keys that only contain a private key. It is commonly used for SSH keys.

The following example illustrates the format: 6a:80:5c:33:a9:43:ea:b0:96:12:8a:64:96:30:ef:4a:8a:96:86:ce:f4:c7:be:10:24:8e:2b:60:9e:f3:59:53

Issuer
String (read-only)
Default Value: ""

The issuer of the certificate. This field contains a string representation of the name of the issuing authority for the certificate.

KeyPassword
String
Default Value: ""

The password for the certificate's private key (if any).

Some certificate stores may individually protect certificates' private keys, separate from the standard protection offered by the StorePassword. This field can be used to read such password-protected private keys.

NOTE: This property defaults to the value of StorePassword. To clear it, you must set the property to the empty string (""). It can be set at any time, but when the private key's password is different from the store's password, then it must be set before calling PrivateKey.

PrivateKey
String (read-only)
Default Value: ""

The private key of the certificate (if available). The key is provided as PEM/Base64-encoded data.

NOTE: The PrivateKey may be available but not exportable. In this case, PrivateKey returns an empty string.

PrivateKeyAvailable
boolean (read-only)
Default Value: False

Whether a PrivateKey is available for the selected certificate. If PrivateKeyAvailable is True, the certificate may be used for authentication purposes (e.g., server authentication).

PrivateKeyContainer
String (read-only)
Default Value: ""

The name of the PrivateKey container for the certificate (if available). This functionality is available only on Windows platforms.

PublicKey
String (read-only)
Default Value: ""

The public key of the certificate. The key is provided as PEM/Base64-encoded data.

PublicKeyAlgorithm
String (read-only)
Default Value: ""

The textual description of the certificate's public key algorithm. The property contains either the name of the algorithm (e.g., "RSA" or "RSA_DH") or an object identifier (OID) string representing the algorithm.

PublicKeyLength
int (read-only)
Default Value: 0

The length of the certificate's public key (in bits). Common values are 512, 1024, and 2048.

SerialNumber
String (read-only)
Default Value: ""

The serial number of the certificate encoded as a string. The number is encoded as a series of hexadecimal digits, with each pair representing a byte of the serial number.

SignatureAlgorithm
String (read-only)
Default Value: ""

The text description of the certificate's signature algorithm. The property contains either the name of the algorithm (e.g., "RSA" or "RSA_MD5RSA") or an object identifier (OID) string representing the algorithm.

Store
String
Default Value: "MY"

The name of the certificate store for the client certificate.

The StoreType field denotes the type of the certificate store specified by Store. If the store is password-protected, specify the password in StorePassword.

Store is used in conjunction with the Subject field to specify client certificates. If Store has a value, and Subject or Encoded is set, a search for a certificate is initiated. Please see the Subject field for details.

Designations of certificate stores are platform dependent.

The following designations are the most common User and Machine certificate stores in Windows:


MY	A certificate store holding personal certificates with their associated private keys.
CA	Certifying authority certificates.
ROOT	Root certificates.

In Java, the certificate store normally is a file containing certificates and optional private keys.

When the certificate store type is cstPFXFile, this property must be set to the name of the file. When the type is cstPFXBlob, the property must be set to the binary contents of a PFX file (i.e., PKCS#12 certificate store).

StoreB
byte []
Default Value: "MY"

The name of the certificate store for the client certificate.

The StoreType field denotes the type of the certificate store specified by Store. If the store is password-protected, specify the password in StorePassword.

Designations of certificate stores are platform dependent.

The following designations are the most common User and Machine certificate stores in Windows:


MY	A certificate store holding personal certificates with their associated private keys.
CA	Certifying authority certificates.
ROOT	Root certificates.

In Java, the certificate store normally is a file containing certificates and optional private keys.

StorePassword
String
Default Value: ""

If the type of certificate store requires a password, this field is used to specify the password needed to open the certificate store.

StoreType
int
Default Value: 0

The type of certificate store for this certificate.

The component supports both public and private keys in a variety of formats. When the cstAuto value is used, the component will automatically determine the type. This field can take one of the following values:


0 (cstUser - default)	For Windows, this specifies that the certificate store is a certificate store owned by the current user. NOTE: This store type is not available in Java.
1 (cstMachine)	For Windows, this specifies that the certificate store is a machine store. NOTE: This store type is not available in Java.
2 (cstPFXFile)	The certificate store is the name of a PFX (PKCS#12) file containing certificates.
3 (cstPFXBlob)	The certificate store is a string (binary or Base64-encoded) representing a certificate store in PFX (PKCS#12) format.
4 (cstJKSFile)	The certificate store is the name of a Java Key Store (JKS) file containing certificates. NOTE: This store type is only available in Java.
5 (cstJKSBlob)	The certificate store is a string (binary or Base64-encoded) representing a certificate store in Java Key Store (JKS) format. NOTE: This store type is only available in Java.
6 (cstPEMKeyFile)	The certificate store is the name of a PEM-encoded file that contains a private key and an optional certificate.
7 (cstPEMKeyBlob)	The certificate store is a string (binary or Base64-encoded) that contains a private key and an optional certificate.
8 (cstPublicKeyFile)	The certificate store is the name of a file that contains a PEM- or DER-encoded public key certificate.
9 (cstPublicKeyBlob)	The certificate store is a string (binary or Base64-encoded) that contains a PEM- or DER-encoded public key certificate.
10 (cstSSHPublicKeyBlob)	The certificate store is a string (binary or Base64-encoded) that contains an SSH-style public key.
11 (cstP7BFile)	The certificate store is the name of a PKCS#7 file containing certificates.
12 (cstP7BBlob)	The certificate store is a string (binary) representing a certificate store in PKCS#7 format.
13 (cstSSHPublicKeyFile)	The certificate store is the name of a file that contains an SSH-style public key.
14 (cstPPKFile)	The certificate store is the name of a file that contains a PPK (PuTTY Private Key).
15 (cstPPKBlob)	The certificate store is a string (binary) that contains a PPK (PuTTY Private Key).
16 (cstXMLFile)	The certificate store is the name of a file that contains a certificate in XML format.
17 (cstXMLBlob)	The certificate store is a string that contains a certificate in XML format.
18 (cstJWKFile)	The certificate store is the name of a file that contains a JWK (JSON Web Key).
19 (cstJWKBlob)	The certificate store is a string that contains a JWK (JSON Web Key).
21 (cstBCFKSFile)	The certificate store is the name of a file that contains a BCFKS (Bouncy Castle FIPS Key Store). NOTE: This store type is only available in Java and .NET.
22 (cstBCFKSBlob)	The certificate store is a string (binary or Base64-encoded) representing a certificate store in BCFKS (Bouncy Castle FIPS Key Store) format. NOTE: This store type is only available in Java and .NET.
23 (cstPKCS11)	The certificate is present on a physical security key accessible via a PKCS#11 interface. To use a security key, the necessary data must first be collected using the CertMgr component. The ListStoreCertificates method may be called after setting CertStoreType to `cstPKCS11`, CertStorePassword to the PIN, and CertStore to the full path of the PKCS#11 DLL. The certificate information returned in the CertList event's `CertEncoded` parameter may be saved for later use. When using a certificate, pass the previously saved security key information as the Store and set StorePassword to the PIN. Code Example. SSH Authentication with Security Key: `certmgr.CertStoreType = CertStoreTypes.cstPKCS11; certmgr.OnCertList += (s, e) => { secKeyBlob = e.CertEncoded; }; certmgr.CertStore = @"C:\Program Files\OpenSC Project\OpenSC\pkcs11\opensc-pkcs11.dll"; certmgr.CertStorePassword = "123456"; //PIN certmgr.ListStoreCertificates(); sftp.SSHCert = new Certificate(CertStoreTypes.cstPKCS11, secKeyBlob, "123456", "*"); sftp.SSHUser = "test"; sftp.SSHLogon("myhost", 22);`
99 (cstAuto)	The store type is automatically detected from the input data. This setting may be used with both public and private keys and can detect any of the supported formats automatically.

SubjectAltNames
String (read-only)
Default Value: ""

Comma-separated lists of alternative subject names for the certificate.

ThumbprintMD5
String (read-only)
Default Value: ""

The MD5 hash of the certificate. It is primarily used for X.509 certificates. If the hash does not already exist, it is automatically computed.

ThumbprintSHA1
String (read-only)
Default Value: ""

The SHA-1 hash of the certificate. It is primarily used for X.509 certificates. If the hash does not already exist, it is automatically computed.

ThumbprintSHA256
String (read-only)
Default Value: ""

The SHA-256 hash of the certificate. It is primarily used for X.509 certificates. If the hash does not already exist, it is automatically computed.

Usage
String (read-only)
Default Value: ""

The text description of UsageFlags.

This value will be one or more of the following strings and will be separated by commas:

Digital Signature
Non-Repudiation
Key Encipherment
Data Encipherment
Key Agreement
Certificate Signing
CRL Signing
Encipher Only

If the provider is OpenSSL, the value is a comma-separated list of X.509 certificate extension names.

UsageFlags
int (read-only)
Default Value: 0

The flags that show intended use for the certificate. The value of UsageFlags is a combination of the following flags:


0x80	Digital Signature
0x40	Non-Repudiation
0x20	Key Encipherment
0x10	Data Encipherment
0x08	Key Agreement
0x04	Certificate Signing
0x02	CRL Signing
0x01	Encipher Only

Please see the Usage field for a text representation of UsageFlags.

This functionality currently is not available when the provider is OpenSSL.

Version
String (read-only)
Default Value: ""

The certificate's version number. The possible values are the strings "V1", "V2", and "V3".

Subject
String
Default Value: ""

The subject of the certificate used for client authentication.

This field will be populated with the full subject of the loaded certificate. When loading a certificate, the subject is used to locate the certificate in the store.

If an exact match is not found, the store is searched for subjects containing the value of the property.

If a match is still not found, the property is set to an empty string, and no certificate is selected.

The special value "*" picks a random certificate in the certificate store.

The certificate subject is a comma-separated list of distinguished name fields and values. For instance, "CN=www.server.com, OU=test, C=US, E=example@email.com". Common fields and their meanings are as follows:


Field	Meaning
CN	Common Name. This is commonly a hostname like www.server.com.
O	Organization
OU	Organizational Unit
L	Locality
S	State
C	Country
E	Email Address

If a field value contains a comma, it must be quoted.

Encoded
String
Default Value: ""

The certificate (PEM/Base64 encoded). This field is used to assign a specific certificate. The Store and Subject fields also may be used to specify a certificate.

When Encoded is set, a search is initiated in the current Store for the private key of the certificate. If the key is found, Subject is updated to reflect the full subject of the selected certificate; otherwise, Subject is set to an empty string.

EncodedB
byte []
Default Value: ""

The certificate (PEM/Base64 encoded). This field is used to assign a specific certificate. The Store and Subject fields also may be used to specify a certificate.

Constructors

public Certificate();

Creates a instance whose properties can be set.

public Certificate( certificateFile);

Opens CertificateFile and reads out the contents as an X.509 public key.

public Certificate( encoded);

Parses Encoded as an X.509 public key.

public Certificate( storeType,  store,  storePassword,  subject);

StoreType identifies the type of certificate store to use. See for descriptions of the different certificate stores. Store is a file containing the certificate store. StorePassword is the password used to protect the store.

After the store has been successfully opened, the component will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN). The Subject parameter can also take an MD5, SHA-1, or SHA-256 thumbprint of the certificate to load in a "Thumbprint=value" format.

public Certificate( storeType,  store,  storePassword,  subject,  configurationString);

ConfigurationString is a newline-separated list of name-value pairs that may be used to modify the default behavior. Possible values include "PersistPFXKey", which shows whether or not the PFX key is persisted after performing operations with the private key. This correlates to the PKCS12_NO_PERSIST_KEY CryptoAPI option. The default value is True (the key is persisted). "Thumbprint" - an MD5, SHA-1, or SHA-256 thumbprint of the certificate to load. When specified, this value is used to select the certificate in the store. This is applicable to the cstUser , cstMachine , cstPublicKeyFile , and cstPFXFile store types. "UseInternalSecurityAPI" shows whether the platform (default) or the internal security API is used when performing certificate-related operations.

public Certificate( storeType,  store,  storePassword,  encoded);

After the store has been successfully opened, the component will load Encoded as an X.509 certificate and search the opened store for a corresponding private key.

public Certificate( storeType,  store,  storePassword,  subject);

StoreType identifies the type of certificate store to use. See for descriptions of the different certificate stores. Store is a byte array containing the certificate data. StorePassword is the password used to protect the store.

public Certificate( storeType,  store,  storePassword,  subject,  configurationString);

public Certificate( storeType,  store,  storePassword,  encoded);

After the store has been successfully opened, the component will load Encoded as an X.509 certificate and search the opened store for a corresponding private key.

Prompt Type

A registered prompt.

Remarks

This type represents a registered prompt that can be requested by the client.

The following fields are available:

Description
Name

Fields

Description
String
Default Value: ""

The brief, human-readable description of what the prompt does.

This field holds a brief, human-readable description of what the prompt does, which is critical in helping the client to understand the purpose and functionality of the prompt.

Name
String
Default Value: ""

The unique name associated with the prompt.

This field identifies the unique name associated with the prompt.

Constructors

public Prompt();

PromptArg Type

A prompt argument to be registered.

Remarks

This type represents a prompt argument that is yet to be registered.

The following fields are available:

Description
Name
Required

Fields

Description
String
Default Value: ""

The brief, human-readable description of what information should be provided to this argument.

This field holds a brief, human-readable description of what information should be provided to this argument.

Name
String
Default Value: ""

The unique name associated with the prompt argument.

This field identifies the unique name associated with the prompt argument.

Required
boolean
Default Value: True

Whether the prompt argument must be supplied by the client when requesting the prompt.

This field indicates whether the prompt argument must be supplied by the client when requesting the prompt.

Constructors

public PromptArg();

Resource Type

A registered resource.

Remarks

This type represents a registered resource that can be requested by the client.

The following fields are available:

Description
Mimetype
Name
Size
Uri

Fields

Description
String
Default Value: ""

The brief, human-readable description of the purpose of the resource as well as appropriate use cases.

This field holds a brief, human-readable description of the purpose of the resource as well as appropriate use cases.

Mimetype
String
Default Value: ""

The media type of the resource content.

This field holds the media type of resource content (e.g., text/plain, image/png, etc.) and helps clients interpret the resource correctly and determine how it should be processed or displayed.

Name
String
Default Value: ""

The display name associated with the resource.

This field indicates the display associated with the resource that is shown to end users by the client.

Size
int (read-only)
Default Value: 0

The size of the resource content, in bytes.

This field indicates the size of the resource content, in bytes.

Uri
String
Default Value: ""

The unique resource identifier associated with the resource.

This field identifies the unique resource identifier associated with the resource.

Constructors

public Resource();

SamplingMessage Type

An individual message in a sampling request.

Remarks

This type represents an individual message within a sampling request received by the server.

The following fields are available:

Role
Text

Fields

Role
int (read-only)
Default Value: 0

The speaker or author of the message.

This field indicates who authored each message and helps provide conversational context to language models. Valid roles include:


`0 (rtUser)`	Message from the end user requesting assistance.
`1 (rtAssistant)`	Message from the client providing responses.

Text
String
Default Value: ""

The instruction that can be passed into the client's language model.

This field contains natural language describing an instruction that can be passed into the client's language model (e.g., Review python code, Summarize an article, or Provide an example of using the /n software MCP SDK).

Constructors

public SamplingMessage();

ServerSettings Type

The embedded HTTP server settings used by the component.

Remarks

This type describes the current embedded HTTP server settings used by the component. The fields are used to configure the server.

The following fields are available:

AllowedAuthMethods
LocalHost
LocalPort
Timeout

Fields

AllowedAuthMethods
String
Default Value: "Anonymous,Basic,Digest,NTLM,Negotiate"

Specifies the authentication schemes that the component will allow.

This field must be set to a valid comma-separated string of authentication scheme values that the embedded server will allow. Possible values are as follows:

Anonymous: Unauthenticated connection requests will be allowed.
Basic: HTTP Basic authentication is allowed.
Digest: Digest authentication is allowed.
NTLM: NTLM authentication is allowed.
Negotiate: Windows Negotiate (Kerberos) authentication is allowed.

LocalHost
String
Default Value: ""

Specifies the name of the local host or user-assigned IP interface through which connections are initiated or accepted.

This field contains the name of the local host as obtained by the gethostname() system call, or if the user has assigned an IP address, the value of that address.

In multihomed hosts (machines with more than one IP interface) setting LocalHost to the IP address of an interface will make the component initiate connections (or accept in the case of server components) only through that interface. It is recommended to provide an IP address rather than a hostname when setting this field to ensure the desired interface is used.

If the component is connected, the LocalHost field shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multihomed hosts (machines with more than one IP interface).

NOTE: LocalHost is not persistent. You must always set it in code, and never in the property window.

LocalPort
int
Default Value: 0

Includes the Transmission Control Protocol (TCP) port in the local host where the component listens.

This field must be set before the component can start listening. If this is set to 0, then the TCP/IP subsystem will pick a port number at random.

The service port is not shared among servers, so two components cannot be listening on the same port at the same time.

Timeout
int
Default Value: 60

Specifies the timeout in seconds for the component.

If this is set to 0, all operations will run uninterrupted until successful completion or an error condition is encountered.

If this is set to a positive value, the component will wait for the operation to complete before returning control.

If the timeout expires, and the operation is not yet complete, the component throws an exception.

Note that all timeouts are inactivity timeouts, meaning the timeout period is extended by the value specified in this field when any amount of data is successfully sent or received.

Constructors

public ServerSettings();

Creates an empty settings instance whose properties can be set.

Tool Type

A registered tool.

Remarks

This type represents a registered tool that can be requested by the client.

The following fields are available:

Description
Name

Fields

Description
String
Default Value: ""

The brief, human-readable description of what the tool does.

This field holds a brief, human-readable description of what the tool does, which is critical in helping the client to understand when the tool should be invoked.

Name
String
Default Value: ""

The unique name associated with the tool.

This field identifies the unique name associated with the tool.

Constructors

public Tool();

ToolParam Type

A tool parameter to be registered.

Remarks

This type represents a tool parameter that is yet to be registered.

The following fields are available:

ParamType
Value

Fields

ParamType
int
Default Value: 0

The type of data associated with the tool parameter.

This field indicates the type of data associated with the tool parameter.

Valid data types include:

0 (ptString)
1 (ptNumber)
2 (ptBool)
3 (ptArray)
4 (ptObject)

Value
String
Default Value: ""

The value associated with the tool parameter.

This field contains the value associated with the tool parameter.

Constructors

public ToolParam();

Config Settings (MCPServer Component)

The component accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, access to these internal properties is provided through the Config method.

MCPServer Config Settings

LogLevel: Specifies the level of detail that is logged.

This configuration controls the level of detail that is logged through the Log event. Possible values are:


0 (None)	No messages are logged.
1 (Info - Default)	Informational events are logged.
2 (Verbose)	Detailed data is logged.
3 (Debug)	Debug data including all relevant sent and received NFS operations are logged.

MaxTokens: Specifies the maximum number of tokens to generate when sampling the client's LLM.

This setting controls the maximum number of tokens a client's LLM can generate in response to a call to SendSamplingRequest. The default value is 100.

PageSizePrompts: Specifies the page size to use when responding to prompt listing requests from the client.

This setting controls the page size when listing prompts. The default value is 100.

The receiving MCP client should also support pagination.

PageSizeResources: Specifies the page size to use when responding to resource listing requests from the client.

This setting controls the page size when listing resources. The default value is 100.

The receiving MCP client should also support pagination.

PageSizeTools: Specifies the page size to use when responding to tool listing requests from the client.

This setting controls the page size when listing tools. The default value is 100.

The receiving MCP client should also support pagination.

Base Config Settings

BuildInfo: Information about the product's build.

When queried, this setting will return a string containing information about the product's build.

GUIAvailable: Whether or not a message loop is available for processing events.

In a GUI-based application, long-running blocking operations may cause the application to stop responding to input until the operation returns. The component will attempt to discover whether or not the application has a message loop and, if one is discovered, it will process events in that message loop during any such blocking operation.

In some non-GUI applications, an invalid message loop may be discovered that will result in errant behavior. In these cases, setting GUIAvailable to false will ensure that the component does not attempt to process external events.

LicenseInfo: Information about the current license.

When queried, this setting will return a string containing information about the license this instance of a component is using. It will return the following information:

Product: The product the license is for.
Product Key: The key the license was generated from.
License Source: Where the license was found (e.g., RuntimeLicense, License File).
License Type: The type of license installed (e.g., Royalty Free, Single Server).
Last Valid Build: The last valid build number for which the license will work.

MaskSensitiveData: Whether sensitive data is masked in log messages.

In certain circumstances it may be beneficial to mask sensitive data, like passwords, in log messages. Set this to true to mask sensitive data. The default is true.

This setting only works on these components: AS3Receiver, AS3Sender, Atom, Client(3DS), FTP, FTPServer, IMAP, OFTPClient, SSHClient, SCP, Server(3DS), Sexec, SFTP, SFTPServer, SSHServer, TCPClient, TCPServer.

UseDaemonThreads: Whether threads created by the component are daemon threads.

If set to True (default), when the component creates a thread, the thread's Daemon property will be explicitly set to True. When set to False, the component will not set the Daemon property on the created thread. The default value is True.

UseInternalSecurityAPI: Whether or not to use the system security libraries or an internal implementation.

When set to false, the component will use the system security libraries by default to perform cryptographic functions where applicable.

Setting this configuration setting to true tells the component to use the internal implementation instead of using the system security libraries.

This setting is set to false by default on all platforms.

Trappable Errors (MCPServer Component)

MCPServer Errors

104	The component is already listening.