Model Context Protocol in OCaml
anil.recoil.org
1(** MCP SDK - Model Context Protocol SDK for OCaml *)
2
3open Mcp
4open Jsonrpc
5
6(** SDK version *)
7val version : string
8
9(** Logging utilities *)
10module Log : sig
11 type level = Debug | Info | Warning | Error
12
13 val string_of_level : level -> string
14
15 val log : level -> string -> unit
16 val debug : string -> unit
17 val info : string -> unit
18 val warning : string -> unit
19 val error : string -> unit
20end
21
22(** Context for tools and resources *)
23module Context : sig
24 type t = {
25 request_id: RequestId.t option;
26 lifespan_context: (string * Json.t) list;
27 mutable progress_token: ProgressToken.t option;
28 }
29
30 val create : ?request_id:RequestId.t -> ?lifespan_context:(string * Json.t) list -> unit -> t
31 val get_context_value : t -> string -> Json.t option
32 val report_progress : t -> float -> float -> JSONRPCMessage.t option
33end
34
35(** Tools for the MCP server *)
36module Tool : sig
37 type handler = Context.t -> Json.t -> (Json.t, string) result
38
39 type t = {
40 name: string;
41 description: string option;
42 input_schema: Json.t;
43 handler: handler;
44 }
45
46 val create : name:string -> ?description:string -> input_schema:Json.t -> handler:handler -> unit -> t
47 val to_json : t -> Json.t
48end
49
50(** Resources for the MCP server *)
51module Resource : sig
52 type handler = Context.t -> string list -> (string, string) result
53
54 type t = {
55 uri_template: string;
56 description: string option;
57 mime_type: string option;
58 handler: handler;
59 }
60
61 val create : uri_template:string -> ?description:string -> ?mime_type:string -> handler:handler -> unit -> t
62 val to_json : t -> Json.t
63end
64
65(** Prompts for the MCP server *)
66module Prompt : sig
67 type argument = {
68 name: string;
69 description: string option;
70 required: bool;
71 }
72
73 type message = {
74 role: Role.t;
75 content: content;
76 }
77
78 type handler = Context.t -> (string * string) list -> (message list, string) result
79
80 type t = {
81 name: string;
82 description: string option;
83 arguments: argument list;
84 handler: handler;
85 }
86
87 val create : name:string -> ?description:string -> ?arguments:argument list -> handler:handler -> unit -> t
88 val create_argument : name:string -> ?description:string -> ?required:bool -> unit -> argument
89 val to_json : t -> Json.t
90end
91
92(** Server implementation *)
93module Server : sig
94 type startup_hook = unit -> unit
95 type shutdown_hook = unit -> unit
96
97 type t = {
98 name: string;
99 version: string;
100 protocol_version: string;
101 mutable capabilities: Json.t;
102 mutable tools: Tool.t list;
103 mutable resources: Resource.t list;
104 mutable prompts: Prompt.t list;
105 mutable lifespan_context: (string * Json.t) list;
106 startup_hook: startup_hook option;
107 shutdown_hook: shutdown_hook option;
108 }
109
110 val create : name:string -> ?version:string -> ?protocol_version:string -> ?startup_hook:startup_hook -> ?shutdown_hook:shutdown_hook -> unit -> t
111 val register_tool : t -> Tool.t -> unit
112 val register_resource : t -> Resource.t -> unit
113 val register_prompt : t -> Prompt.t -> unit
114 val default_capabilities : ?with_tools:bool -> ?with_resources:bool -> ?with_prompts:bool -> unit -> Json.t
115 val update_capabilities : t -> Json.t -> unit
116
117 val process_message : t -> Json.t -> JSONRPCMessage.t option
118 val run : t -> unit
119end
120
121(** Helper functions for creating common objects *)
122val make_text_content : string -> content
123val make_tool_schema : (string * string * string) list -> string list -> Json.t
124
125(** Syntax sugar for creating an MCP server *)
126module MakeServer : functor (S : sig
127 val name : string
128 val version : string option
129end) -> sig
130 val _config : string * string option (* Used to prevent unused parameter warning *)
131 val server : Server.t
132
133 val tool : ?name:string option -> ?description:string -> ?schema_properties:(string * string * string) list -> ?schema_required:string list -> (Json.t -> Json.t) -> Tool.t
134 val resource : ?uri_template:string option -> ?description:string -> ?mime_type:string -> (string list -> string) -> Resource.t
135 val prompt : ?name:string option -> ?description:string -> ?arguments:(string * string option * bool) list -> ((string * string) list -> Prompt.message list) -> Prompt.t
136 val run : ?with_tools:bool -> ?with_resources:bool -> ?with_prompts:bool -> unit -> unit
137end