this repo has no description
Add example servers to demonstrate MCP features
- audio_example.ml: Demonstrates audio content and tool results with multiple content types
- resource_template_example.ml: Shows resource templates and embedded resources
- completion_example.ml: Implements completion support with a custom tool
🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>
+514
+145
bin/audio_example.ml
+145
bin/audio_example.ml
···
1
+
open Mcp
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open Mcp_sdk
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+
4
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(* Helper for extracting string value from JSON *)
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let get_string_param json name =
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match json with
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| `Assoc fields ->
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(match List.assoc_opt name fields with
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| Some (`String value) -> value
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| _ -> raise (Failure (Printf.sprintf "Missing or invalid parameter: %s" name)))
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| _ -> raise (Failure "Expected JSON object")
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+
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(* Create a server *)
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let server = create_server
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~name:"OCaml MCP Audio Example"
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~version:"0.1.0"
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~protocol_version:"2024-11-05"
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()
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+
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(* Define startup and shutdown hooks *)
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let startup () =
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Printf.printf "AudioExampleServer is starting up!\n";
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flush stdout;
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Log.info "AudioExampleServer is starting up!"
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+
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let shutdown () =
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Printf.printf "AudioExampleServer is shutting down. Goodbye!\n";
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flush stdout;
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Log.info "AudioExampleServer is shutting down. Goodbye!"
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+
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(* Register the hooks *)
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let () =
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set_startup_hook server startup;
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set_shutdown_hook server shutdown
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+
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(* Helper to create audio content *)
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let make_audio_content data mime_type =
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let audio_content = AudioContent.{
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data;
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mime_type;
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annotations = None;
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} in
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Audio audio_content
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+
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(* Define and register an audio tool *)
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let _ = add_tool server
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~name:"generate_audio_description"
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~description:"Generates a description with an audio sample"
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~schema_properties:[
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("text", "string", "The text to describe with audio");
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("frequency", "number", "The frequency in Hz for the tone (optional)");
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]
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~schema_required:["text"]
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(fun args ->
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try
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let text = get_string_param args "text" in
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let frequency =
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try
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match List.assoc_opt "frequency" (match args with `Assoc l -> l | _ -> []) with
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| Some (`Int f) -> f
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| Some (`Float f) -> int_of_float f
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| _ -> 440 (* Default to A440 *)
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with _ -> 440
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in
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(* This is just a placeholder for actual audio data *)
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(* In a real implementation, you would generate a WAV or MP3 file and base64 encode it *)
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let audio_data = Printf.sprintf "BASE64_ENCODED_AUDIO_DATA_FOR_%d_HZ_TONE" frequency in
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(* Create a response with both text and audio content *)
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CallToolResult.yojson_of_t CallToolResult.{
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content = [
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Text TextContent.{ text = Printf.sprintf "Description: %s (with %d Hz tone)" text frequency; annotations = None };
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Audio AudioContent.{ data = audio_data; mime_type = "audio/wav"; annotations = None }
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];
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is_error = false;
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meta = None
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}
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with
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| Failure msg ->
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Log.error (Printf.sprintf "Error in audio tool: %s" msg);
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CallToolResult.yojson_of_t CallToolResult.{
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content = [
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Text TextContent.{
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text = Printf.sprintf "Error: %s" msg;
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annotations = None
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}
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];
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is_error = true;
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meta = None
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}
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)
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(* Define and register a prompt example with audio *)
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let _ = add_prompt server
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~name:"audio-description-prompt"
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~description:"A prompt with audio and text content"
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~arguments:[
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("description", Some "Text description to accompany the audio", true);
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("frequency", Some "Frequency in Hz for the audio tone", false);
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]
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(fun args ->
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let description =
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try List.assoc "description" args
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with Not_found -> "No description provided"
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in
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let frequency =
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try int_of_string (List.assoc "frequency" args)
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with _ -> 440 (* Default to A440 *)
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in
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(* Placeholder for audio data *)
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let audio_data = Printf.sprintf "BASE64_ENCODED_AUDIO_DATA_FOR_%d_HZ_TONE" frequency in
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+
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[
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Prompt.{
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role = `User;
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content = make_text_content "Here's a sound sample with description:"
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};
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Prompt.{
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role = `User;
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content = make_audio_content audio_data "audio/wav"
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};
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Prompt.{
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role = `User;
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content = make_text_content description
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};
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Prompt.{
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role = `Assistant;
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content = make_text_content "I've received your audio file and description."
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}
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]
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)
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+
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(* Main function *)
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let () =
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(* Print directly to ensure we see output *)
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Printf.printf "Starting AudioExampleServer...\n";
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flush stdout;
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+
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(* Configure the server with appropriate capabilities *)
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ignore (configure_server server ());
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+
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(* Run the server *)
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run_server server
+180
bin/completion_example.ml
+180
bin/completion_example.ml
···
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open Mcp
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open Mcp_sdk
3
+
4
+
(* Helper for extracting string value from JSON *)
5
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let get_string_param json name =
6
+
match json with
7
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| `Assoc fields ->
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(match List.assoc_opt name fields with
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| Some (`String value) -> value
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| _ -> raise (Failure (Printf.sprintf "Missing or invalid parameter: %s" name)))
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| _ -> raise (Failure "Expected JSON object")
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+
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(* Create a server *)
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let server = create_server
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~name:"OCaml MCP Completion Example"
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~version:"0.1.0"
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~protocol_version:"2024-11-05"
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()
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+
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(* Define startup and shutdown hooks *)
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let startup () =
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Printf.printf "CompletionServer is starting up!\n";
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flush stdout;
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Log.info "CompletionServer is starting up!"
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+
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let shutdown () =
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Printf.printf "CompletionServer is shutting down. Goodbye!\n";
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flush stdout;
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Log.info "CompletionServer is shutting down. Goodbye!"
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+
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(* Register the hooks *)
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let () =
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set_startup_hook server startup;
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set_shutdown_hook server shutdown
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+
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(* Database of programming languages and their features *)
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let languages = [
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("ocaml", ["functional"; "static typing"; "pattern matching"; "modules"; "type inference"]);
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("python", ["dynamic typing"; "interpreted"; "object-oriented"; "high-level"; "scripting"]);
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("rust", ["memory safety"; "performance"; "static typing"; "ownership"; "zero-cost abstractions"]);
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("javascript", ["dynamic typing"; "interpreted"; "prototypes"; "single-threaded"; "event-driven"]);
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("go", ["concurrency"; "garbage collection"; "simplicity"; "static typing"; "compiled"]);
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]
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(* Helper function to create a completion response *)
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let create_completion values ?(has_more=false) ?(total=None) () =
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Completion.Result.{
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completion = {
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values;
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has_more = Some has_more;
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total;
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};
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meta = None;
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}
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+
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(* Define and register a tool that handles completions *)
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let _ = add_tool server
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~name:"complete"
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~description:"Handles completion requests for programming languages and features"
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~schema_properties:[
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("argument_name", "string", "The name of the argument to complete");
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("argument_value", "string", "The partial value to complete");
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]
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~schema_required:["argument_name"; "argument_value"]
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(fun args ->
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try
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let argument_name = get_string_param args "argument_name" in
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let argument_value = get_string_param args "argument_value" in
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Log.info (Printf.sprintf "Completion request for %s = %s" argument_name argument_value);
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+
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(* Handle different completion requests *)
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let result =
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match argument_name with
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| "language" ->
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(* Complete programming language names *)
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let matches =
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List.filter
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(fun (lang, _) ->
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let lang_lower = String.lowercase_ascii lang in
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let arg_lower = String.lowercase_ascii argument_value in
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String.length lang_lower >= String.length arg_lower &&
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String.sub lang_lower 0 (String.length arg_lower) = arg_lower)
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languages
85
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in
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let values = List.map fst matches in
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create_completion values ~has_more:false ~total:(Some (List.length values)) ()
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+
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| "feature" ->
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(* Complete programming language features *)
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let all_features =
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List.flatten (List.map snd languages) |>
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List.sort_uniq String.compare
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in
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let matches =
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List.filter
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(fun feature ->
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let feature_lower = String.lowercase_ascii feature in
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let arg_lower = String.lowercase_ascii argument_value in
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String.length feature_lower >= String.length arg_lower &&
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String.sub feature_lower 0 (String.length arg_lower) = arg_lower)
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all_features
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in
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create_completion matches ~has_more:false ~total:(Some (List.length matches)) ()
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+
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| _ ->
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(* Default completions for unknown arguments *)
108
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create_completion ["unknown argument"] ()
109
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in
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+
111
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(* Convert to JSON and return *)
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TextContent.yojson_of_t TextContent.{
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text = Yojson.Safe.to_string (Completion.Result.to_result result);
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annotations = None
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}
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with
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| Failure msg ->
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Log.error (Printf.sprintf "Error handling completion request: %s" msg);
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TextContent.yojson_of_t TextContent.{
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text = Printf.sprintf "Error: %s" msg;
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annotations = None
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}
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)
124
+
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(* Define and register a prompt that provides programming language info *)
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let _ = add_prompt server
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~name:"language-info-prompt"
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~description:"A prompt that provides information about programming languages"
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~arguments:[
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("language", Some "Name of the programming language", true);
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]
132
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(fun args ->
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let language =
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try List.assoc "language" args
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with Not_found -> "ocaml" (* Default to OCaml *)
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in
137
+
138
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let features =
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try
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let features = List.assoc (String.lowercase_ascii language) languages in
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String.concat ", " features
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with Not_found -> "unknown language"
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in
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+
145
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[
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Prompt.{
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role = `User;
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content = make_text_content (Printf.sprintf "Tell me about the %s programming language" language)
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};
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Prompt.{
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role = `Assistant;
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content = make_text_content (Printf.sprintf "%s is a programming language with the following features: %s" language features)
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}
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]
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)
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+
157
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(* Main function *)
158
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let () =
159
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(* Print directly to ensure we see output *)
160
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Printf.printf "Starting CompletionServer...\n";
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flush stdout;
162
+
163
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(* Set custom capabilities to indicate support for completions *)
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let capabilities = `Assoc [
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("completions", `Assoc []); (* Indicate support for completions *)
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("prompts", `Assoc [
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("listChanged", `Bool true)
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]);
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("resources", `Assoc [
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("listChanged", `Bool true);
171
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("subscribe", `Bool true)
172
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]);
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("tools", `Assoc [
174
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("listChanged", `Bool true)
175
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])
176
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] in
177
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set_capabilities server capabilities;
178
+
179
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(* Run the server *)
180
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run_server server
+15
bin/dune
+15
bin/dune
···
5
5
(executable
6
6
(name capitalize_sdk)
7
7
(modules capitalize_sdk)
8
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(libraries mcp mcp_sdk yojson unix))
9
+
10
+
(executable
11
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(name audio_example)
12
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(modules audio_example)
13
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(libraries mcp mcp_sdk yojson unix))
14
+
15
+
(executable
16
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(name resource_template_example)
17
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(modules resource_template_example)
18
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(libraries mcp mcp_sdk yojson unix))
19
+
20
+
(executable
21
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(name completion_example)
22
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(modules completion_example)
8
23
(libraries mcp mcp_sdk yojson unix))
+174
bin/resource_template_example.ml
+174
bin/resource_template_example.ml
···
1
+
open Mcp
2
+
open Mcp_sdk
3
+
4
+
(* Helper for extracting string value from JSON *)
5
+
let get_string_param json name =
6
+
match json with
7
+
| `Assoc fields ->
8
+
(match List.assoc_opt name fields with
9
+
| Some (`String value) -> value
10
+
| _ -> raise (Failure (Printf.sprintf "Missing or invalid parameter: %s" name)))
11
+
| _ -> raise (Failure "Expected JSON object")
12
+
13
+
(* Create a server *)
14
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let server = create_server
15
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~name:"OCaml MCP Resource Template Example"
16
+
~version:"0.1.0"
17
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~protocol_version:"2024-11-05"
18
+
()
19
+
20
+
(* Define startup and shutdown hooks *)
21
+
let startup () =
22
+
Printf.printf "ResourceTemplateServer is starting up!\n";
23
+
flush stdout;
24
+
Log.info "ResourceTemplateServer is starting up!"
25
+
26
+
let shutdown () =
27
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Printf.printf "ResourceTemplateServer is shutting down. Goodbye!\n";
28
+
flush stdout;
29
+
Log.info "ResourceTemplateServer is shutting down. Goodbye!"
30
+
31
+
(* Register the hooks *)
32
+
let () =
33
+
set_startup_hook server startup;
34
+
set_shutdown_hook server shutdown
35
+
36
+
(* Database of "documents" *)
37
+
let documents = [
38
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("doc1", "This is the first document content");
39
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("doc2", "This document contains information about OCaml");
40
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("doc3", "MCP protocol is a standard for LLM-based applications");
41
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("doc4", "Resource templates allow for parameterized resources");
42
+
]
43
+
44
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(* Define and register a resource template for documents *)
45
+
let _ = add_resource server
46
+
~uri_template:"document://{id}"
47
+
~description:"Get a document by ID"
48
+
~mime_type:"text/plain"
49
+
(fun params ->
50
+
match params with
51
+
| [id] ->
52
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begin
53
+
try
54
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let content = List.assoc id documents in
55
+
content
56
+
with Not_found ->
57
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Printf.sprintf "Error: Document '%s' not found" id
58
+
end
59
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| _ -> "Error: Invalid document ID"
60
+
)
61
+
62
+
(* Define and register a list documents resource *)
63
+
let _ = add_resource server
64
+
~uri_template:"documents://list"
65
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~description:"List all available documents"
66
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~mime_type:"text/plain"
67
+
(fun _ ->
68
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let doc_list =
69
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String.concat "\n"
70
+
(List.map (fun (id, _) -> Printf.sprintf "- %s" id) documents)
71
+
in
72
+
Printf.sprintf "Available Documents:\n%s" doc_list
73
+
)
74
+
75
+
(* Define and register a tool that uses resource references *)
76
+
let _ = add_tool server
77
+
~name:"get_document"
78
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~description:"Gets a document by ID using resource references"
79
+
~schema_properties:[
80
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("document_id", "string", "The ID of the document to retrieve");
81
+
]
82
+
~schema_required:["document_id"]
83
+
(fun args ->
84
+
try
85
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let doc_id = get_string_param args "document_id" in
86
+
87
+
(* Create a resource reference *)
88
+
let ref = ResourceReference.{ uri = Printf.sprintf "document://%s" doc_id } in
89
+
(* Convert to JSON for logging purposes *)
90
+
let _ = ResourceReference.yojson_of_t ref in
91
+
92
+
(* Return the reference *)
93
+
CallToolResult.yojson_of_t CallToolResult.{
94
+
content = [
95
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Text TextContent.{ text = Printf.sprintf "Resource reference for document %s:" doc_id; annotations = None };
96
+
Resource EmbeddedResource.{
97
+
resource = `Text TextResourceContents.{
98
+
uri = Printf.sprintf "document://%s" doc_id;
99
+
text = (try List.assoc doc_id documents with Not_found -> "Not found");
100
+
mime_type = Some "text/plain"
101
+
};
102
+
annotations = None
103
+
}
104
+
];
105
+
is_error = false;
106
+
meta = None
107
+
}
108
+
with
109
+
| Failure msg ->
110
+
Log.error (Printf.sprintf "Error in get_document tool: %s" msg);
111
+
CallToolResult.yojson_of_t CallToolResult.{
112
+
content = [
113
+
Text TextContent.{
114
+
text = Printf.sprintf "Error: %s" msg;
115
+
annotations = None
116
+
}
117
+
];
118
+
is_error = true;
119
+
meta = None
120
+
}
121
+
)
122
+
123
+
(* Define and register a prompt that uses resource templates *)
124
+
let _ = add_prompt server
125
+
~name:"document-prompt"
126
+
~description:"A prompt that references document resources"
127
+
~arguments:[
128
+
("document_id", Some "ID of the document to include in the prompt", true);
129
+
]
130
+
(fun args ->
131
+
let doc_id =
132
+
try List.assoc "document_id" args
133
+
with Not_found -> "doc1" (* Default to doc1 *)
134
+
in
135
+
136
+
let doc_text =
137
+
try List.assoc doc_id documents
138
+
with Not_found -> Printf.sprintf "Document '%s' not found" doc_id
139
+
in
140
+
141
+
[
142
+
Prompt.{
143
+
role = `User;
144
+
content = make_text_content (Printf.sprintf "Please summarize the following document (ID: %s):" doc_id)
145
+
};
146
+
Prompt.{
147
+
role = `User;
148
+
content = Resource EmbeddedResource.{
149
+
resource = `Text TextResourceContents.{
150
+
uri = Printf.sprintf "document://%s" doc_id;
151
+
text = doc_text;
152
+
mime_type = Some "text/plain"
153
+
};
154
+
annotations = None
155
+
}
156
+
};
157
+
Prompt.{
158
+
role = `Assistant;
159
+
content = make_text_content "I'll help summarize this document for you."
160
+
}
161
+
]
162
+
)
163
+
164
+
(* Main function *)
165
+
let () =
166
+
(* Print directly to ensure we see output *)
167
+
Printf.printf "Starting ResourceTemplateServer...\n";
168
+
flush stdout;
169
+
170
+
(* Configure the server with appropriate capabilities *)
171
+
ignore (configure_server server ());
172
+
173
+
(* Run the server *)
174
+
run_server server