mcp-vala/docs/api-reference.md

MCP Vala Library API Reference

This document provides comprehensive API documentation for the MCP Vala library, covering all public classes, interfaces, and methods.

Table of Contents

1. Core Namespace
2. Types Namespace
3. Resources Namespace
4. Tools Namespace
5. Prompts Namespace
6. Common Namespace

Core Namespace

Mcp.Core.Server

The main server class that orchestrates all MCP functionality.

Constructor

public Server (
    Mcp.Types.Protocol.ServerInfo server_info,
    Mcp.Types.Protocol.ServerCapabilities capabilities
)

Parameters:

• server_info: Information about the server (name, version, description)
• capabilities: Server capabilities (resources, tools, prompts, logging)

Properties

public Mcp.Resources.Manager resource_manager { get; }
public Mcp.Tools.Manager tool_manager { get; }
public Mcp.Prompts.Manager prompt_manager { get; }
public bool is_running { get; }
public bool is_initialized { get; }

Signals

public signal void initialized ();
public signal void shutdown ();

Methods

public async bool start () throws Error
public async void stop ()
public void send_notification (string method, Variant? params = null)

Example

// Create server
var server_info = new Mcp.Types.Protocol.ServerInfo (
    "my-server",
    "1.0.0",
    "My MCP server"
);

var capabilities = new Mcp.Types.Protocol.ServerCapabilities ();
capabilities.logging = true;
capabilities.tools = new Mcp.Types.Protocol.ToolsCapabilities ();

var server = new Mcp.Core.Server (server_info, capabilities);

// Start server
bool started = yield server.start ();
if (started) {
    print ("Server started successfully\n");
}

Jsonrpc Integration

The library now uses Jsonrpc.Server from jsonrpc-glib-1.0 for handling JSON-RPC communication. The custom MessageHandler and StdioTransport classes have been removed in favor of the standard implementation.

Key Benefits

• Standard-compliant JSON-RPC 2.0 implementation
• Robust error handling with Jsonrpc.Error
• Built-in support for async/await patterns
• Proper STDIO transport handling
• Automatic message parsing and formatting

Mcp.Core.Error

Error domain for MCP-specific errors.

Error Codes

public static const int PARSE_ERROR = -32700;
public static const int INVALID_REQUEST = -32600;
public static const int METHOD_NOT_FOUND = -32601;
public static const int INVALID_PARAMS = -32602;
public static const int INTERNAL_ERROR = -32603;
public static const int NOT_FOUND = -32604;
public static const int INVALID_ARGUMENT = -32605;

Convenience Constructors

public static Error PARSE (string message)
public static Error INVALID_REQUEST (string message)
public static Error METHOD_NOT_FOUND (string message)
public static Error INVALID_PARAMS (string message)
public static Error INTERNAL_ERROR (string message)
public static Error NOT_FOUND (string message)
public static Error INVALID_ARGUMENT (string message)

Types Namespace

Mcp.Core.InjectContentLength

Utility class for injecting Content-Length headers into messages.

Methods

public static string process (string message)

Injects the Content-Length header into a JSON-RPC message.

Mcp.Core.StripContentLength

Utility class for stripping Content-Length headers from messages.

Methods

public static string process (string message)

Removes the Content-Length header from a JSON-RPC message.

Mcp.Types.Protocol.ServerInfo

Information about the MCP server.

Constructor

public ServerInfo (
    string name,
    string version,
    string? description = null,
    string? website_url = null
)

Properties

public string name { get; set; }
public string version { get; set; }
public string? description { get; set; }
public string? website_url { get; set; }

Mcp.Types.Protocol.ServerCapabilities

Server capabilities configuration.

Properties

public bool logging { get; set; }
public Mcp.Types.Protocol.CompletionsCapabilities? completions { get; set; }
public Mcp.Types.Protocol.ResourcesCapabilities? resources { get; set; }
public Mcp.Types.Protocol.ToolsCapabilities? tools { get; set; }
public Mcp.Types.Protocol.PromptsCapabilities? prompts { get; set; }

Mcp.Types.Protocol.CompletionsCapabilities

Completion-related capabilities.

Properties

public bool list_changed { get; set; }

Mcp.Types.Protocol.ResourcesCapabilities

Resource-related capabilities.

Properties

public bool subscribe { get; set; }
public bool list_changed { get; set; }

Mcp.Types.Protocol.ToolsCapabilities

Tool-related capabilities.

Properties

public bool list_changed { get; set; }

Mcp.Types.Protocol.PromptsCapabilities

Prompt-related capabilities.

Properties

public bool list_changed { get; set; }

Jsonrpc Integration

The library now uses Jsonrpc.Server from jsonrpc-glib-1.0 for handling JSON-RPC communication. Custom JSON-RPC message types have been removed in favor of the standard implementation.

Communication Pattern

The library internally converts between Json.Node (used for MCP protocol types) and GLib.Variant (used by Jsonrpc.Server) for seamless integration.

Error Handling

Errors are now handled using Jsonrpc.Error for proper JSON-RPC 2.0 error responses.

Mcp.Types.Common

Common content types used across the MCP protocol.

Mcp.Types.Common.ContentBlock

Base interface for content blocks.

Subclasses

public class TextContent : Mcp.Types.Common.ContentBlock
public class ImageContent : Mcp.Types.Common.ContentBlock
public class ResourceContents : Mcp.Types.Common.ContentBlock

Mcp.Types.Common.TextContent

Text content block.

Constructor

public TextContent (string text)

Properties

public string text { get; construct; }
public string type { get; default = "text"; }

Mcp.Types.Common.ImageContent

Image content block.

Constructor

public ImageContent (string data, string mime_type)

Properties

public string data { get; construct; }
public string mime_type { get; construct; }
public string type { get; default = "image"; }

Mcp.Types.Common.ResourceContents

Base interface for resource contents.

Subclasses

public class TextResourceContents : Mcp.Types.Common.ResourceContents
public class BlobResourceContents : Mcp.Types.Common.ResourceContents

Mcp.Types.Common.TextResourceContents

Text-based resource contents.

Constructor

public TextResourceContents (string uri, string text)

Properties

public string uri { get; construct; }
public string text { get; construct; }
public string mime_type { get; default = "text/plain"; }

Mcp.Types.Common.BlobResourceContents

Binary resource contents.

Constructor

public BlobResourceContents (string uri, uint8[] data, string? mime_type = null)

Properties

public string uri { get; construct; }
public uint8[] data { get; construct; }
public string mime_type { get; construct; }

Mcp.Types.Common.Annotations

Resource annotations.

Properties

public double? priority { get; set; }
public string? audience { get; set; }
public bool? expire_time { get; set; }

Mcp.Types.VariantUtils

Utility functions for working with GLib.Variant data structures.

Dictionary Builder Methods

public static VariantBuilder new_dict_builder ()
public static void add_string (VariantBuilder builder, string key, string value)
public static void add_int (VariantBuilder builder, string key, int value)
public static void add_bool (VariantBuilder builder, string key, bool value)
public static void add_double (VariantBuilder builder, string key, double value)
public static void add_variant (VariantBuilder builder, string key, Variant value)

Dictionary Access Methods

public static bool has_key (Variant dict, string key)
public static string get_string (Variant dict, string key, string? default_value = null)
public static int get_int (Variant dict, string key, int default_value = 0)
public static bool get_bool (Variant dict, string key, bool default_value = false)
public static double get_double (Variant dict, string key, double default_value = 0.0)
public static Variant? get_variant (Variant dict, string key)
public static string[] get_string_array (Variant dict, string key)

Array Builder Methods

public static VariantBuilder new_array_builder (string element_type)
public static void add_string_element (VariantBuilder builder, string value)
public static void add_int_element (VariantBuilder builder, int value)
public static void add_bool_element (VariantBuilder builder, bool value)
public static void add_double_element (VariantBuilder builder, double value)
public static void add_variant_element (VariantBuilder builder, Variant value)

Array Access Methods

public static int get_array_size (Variant array)
public static string get_string_element (Variant array, int index)
public static int get_int_element (Variant array, int index)
public static bool get_bool_element (Variant array, int index)
public static double get_double_element (Variant array, int index)
public static Variant get_variant_element (Variant array, int index)

Conversion Methods

public static Json.Node? to_json (Variant variant)
public static Variant? from_json (Json.Node node)

Resources Namespace

Mcp.Resources.Provider

Interface for resource providers.

Methods

public abstract async Gee.ArrayList<Mcp.Resources.Types.Resource> list_resources (string? cursor) throws Error
public abstract async Mcp.Types.Common.ResourceContents read_resource (string uri) throws Error
public virtual async void subscribe (string uri) throws Error
public virtual async void unsubscribe (string uri) throws Error

Mcp.Resources.BaseProvider

Base implementation for resource providers.

Constructor

protected BaseProvider ()

Properties

public signal void resource_updated (string uri);

Methods

public Gee.ArrayList<string> get_subscriptions ()
public bool is_subscribed (string uri)
public void notify_resource_updated (string uri)
protected virtual Mcp.Resources.Types.Resource? get_resource_metadata (string uri)
protected string guess_mime_type (string uri)

Mcp.Resources.Manager

Manages resource providers and handles resource operations.

Methods

public void register_provider (string name, Mcp.Resources.Provider provider)
public void unregister_provider (string name)
public async Gee.ArrayList<Mcp.Resources.Types.Resource> list_resources (string? cursor) throws Error
public async Mcp.Types.Common.ResourceContents read_resource (string uri) throws Error
public async void subscribe (string uri) throws Error
public async void unsubscribe (string uri) throws Error
public async Gee.ArrayList<Mcp.Resources.Types.ResourceTemplate> list_templates () throws Error
public void register_template (string name, Mcp.Resources.Types.ResourceTemplate template)
public void unregister_template (string name)

Mcp.Resources.Types.Resource

Resource definition.

Constructor

public Resource (string uri, string name)

Properties

public string uri { get; set; }
public string name { get; set; }
public string? title { get; set; }
public string? description { get; set; }
public string? mime_type { get; set; }
public Mcp.Types.Common.Annotations? annotations { get; set; }
public int64? size { get; set; }

Methods

public Json.Node to_json ()
public Resource.from_json (Json.Node node) throws Error

Mcp.Resources.Types.ResourceTemplate

Resource template for dynamic resource creation.

Constructor

public ResourceTemplate (string uri_template, string name)

Properties

public string uri_template { get; set; }
public string name { get; set; }
public string? title { get; set; }
public string? description { get; set; }
public string? mime_type { get; set; }
public Mcp.Types.Common.Annotations? annotations { get; set; }

Tools Namespace

Mcp.Tools.Executor

Interface for tool executors.

Methods

public abstract Mcp.Tools.Types.ToolDefinition get_definition () throws Error
public abstract async Mcp.Tools.Types.CallToolResult execute (Variant arguments) throws Error

Mcp.Tools.BaseExecutor

Base implementation for tool executors.

Constructor

protected BaseExecutor (Mcp.Tools.Types.ToolDefinition definition)

Methods

public virtual Mcp.Tools.Types.ToolDefinition get_definition () throws Error
public async Mcp.Tools.Types.CallToolResult execute (Variant arguments) throws Error
protected virtual void validate_arguments (Variant arguments) throws Error
protected Mcp.Tools.Types.CallToolResult create_text_result (string text)
protected Mcp.Tools.Types.CallToolResult create_text_results (string[] texts)
protected Mcp.Tools.Types.CallToolResult create_error_result (Error error)
protected Mcp.Tools.Types.CallToolResult create_structured_result (string text, Variant structured_data)
protected string? get_string_arg (Variant arguments, string name, string? default_value = null)
protected bool get_bool_arg (Variant arguments, string name, bool default_value = false)
protected int get_int_arg (Variant arguments, string name, int default_value = 0)
protected double get_double_arg (Variant arguments, string name, double default_value = 0.0)
protected abstract async Mcp.Tools.Types.CallToolResult do_execute (Variant arguments) throws Error

Mcp.Tools.Manager

Manages tool executors and handles tool operations.

Methods

public void register_executor (string name, Mcp.Tools.Executor executor)
public void unregister_executor (string name)
public async Gee.ArrayList<Mcp.Tools.Types.ToolDefinition> list_tools () throws Error
public async Mcp.Tools.Types.CallToolResult call_tool (string name, Variant arguments) throws Error

Mcp.Tools.Types.ToolDefinition

Tool definition.

Constructor

public ToolDefinition (string name, Variant input_schema)

Properties

public string name { get; set; }
public string? title { get; set; }
public string? description { get; set; }
public Variant input_schema { get; set; }
public Variant? output_schema { get; set; }
public Mcp.Tools.Types.ToolExecution? execution { get; set; }
public Mcp.Tools.Types.ToolAnnotations? annotations { get; set; }

Methods

public Json.Node to_json ()
public ToolDefinition.from_json (Json.Node node) throws Error

Mcp.Tools.Types.CallToolResult

Result of calling a tool.

Constructor

public CallToolResult ()
public CallToolResult (Gee.ArrayList<Mcp.Types.Common.ContentBlock> content)

Properties

public Gee.ArrayList<Mcp.Types.Common.ContentBlock> content { get; set; }
public Variant? structured_content { get; set; }
public bool is_error { get; set; }

Methods

public Json.Node to_json ()
public CallToolResult.from_json (Json.Node node) throws Error

Mcp.Tools.Types.ToolExecutionContext

Context for tool execution with progress tracking.

Constructor

public ToolExecutionContext (string tool_name, Variant arguments)

Properties

public string tool_name { get; construct; }
public Variant arguments { get; construct; }
public bool supports_progress { get; set; }
public bool task_support { get; set; }

Methods

public void report_progress (Mcp.Tools.Types.ToolProgress progress)
public void add_annotation (Mcp.Tools.Types.ToolAnnotation annotation)

Mcp.Tools.Types.ToolProgress

Progress information for long-running tools.

Constructor

public ToolProgress (double progress, string? message = null)

Properties

public double progress { get; set; }
public string? message { get; set; }

Mcp.Tools.Types.ToolAnnotations

Tool execution annotations.

Constructor

public ToolAnnotations ()

Properties

public string? audience { get; set; }
public double? priority { get; set; }
public Gee.ArrayList<Mcp.Tools.Types.ToolAnnotation> annotations { get; set; }

Mcp.Tools.Types.ToolAnnotation

Individual tool annotation.

Constructor

public ToolAnnotation (string type, Variant data)

Properties

public string type { get; set; }
public Variant data { get; set; }

Mcp.Tools.Types.ToolExecution

Tool execution settings.

Constructor

public ToolExecution (string task_support = "forbidden")

Properties

public string task_support { get; set; }
public bool supports_progress { get; set; }

Prompts Namespace

Mcp.Prompts.Template

Interface for prompt templates.

Methods

public abstract Mcp.Prompts.Types.PromptDefinition get_definition ()
public abstract async Mcp.Prompts.Types.GetPromptResult get_prompt (Variant arguments) throws Error

Mcp.Prompts.BaseTemplate

Base implementation for prompt templates.

Constructor

protected BaseTemplate (string name, string? title = null, string? description = null)
protected BaseTemplate (string name, string? title, string? description, Gee.ArrayList<Mcp.Prompts.Types.PromptArgument> arguments)

Methods

public virtual Mcp.Prompts.Types.PromptDefinition get_definition ()
public virtual async Mcp.Prompts.Types.GetPromptResult get_prompt (Variant arguments) throws Error
protected virtual void validate_arguments (Variant arguments) throws Error
protected virtual Gee.ArrayList<Mcp.Prompts.Types.PromptMessage> generate_messages (Variant arguments)
protected void add_argument (string name, string? title = null, string? description = null, bool required = false)
protected string substitute_variables (string template, Variant arguments)
protected Mcp.Types.Common.TextContent create_text_content (string template, Variant arguments)
protected Mcp.Prompts.Types.PromptMessage create_user_message (string template, Variant arguments)
protected Mcp.Prompts.Types.PromptMessage create_assistant_message (string template, Variant arguments)

Mcp.Prompts.Manager

Manages prompt templates and handles prompt operations.

Methods

public void register_template (string name, Mcp.Prompts.Template template)
public void unregister_template (string name)
public async Gee.ArrayList<Mcp.Prompts.Types.PromptDefinition> list_prompts () throws Error
public async Mcp.Prompts.Types.GetPromptResult get_prompt (string name, Variant arguments) throws Error

Mcp.Prompts.Types.PromptDefinition

Prompt definition.

Constructor

public PromptDefinition (string name)

Properties

public string name { get; set; }
public string? title { get; set; }
public string? description { get; set; }
public Gee.ArrayList<Mcp.Prompts.Types.PromptArgument> arguments { get; set; }

Methods

public Json.Node to_json ()
public PromptDefinition.from_json (Json.Node node) throws Error

Mcp.Prompts.Types.PromptArgument

Prompt argument definition.

Constructor

public PromptArgument (string name)

Properties

public string name { get; set; }
public string? title { get; set; }
public string? description { get; set; }
public bool required { get; set; }

Methods

public Json.Node to_json ()
public PromptArgument.from_json (Json.Node node) throws Error

Mcp.Prompts.Types.GetPromptResult

Result of getting a prompt.

Constructor

public GetPromptResult ()

Properties

public string? description { get; set; }
public Gee.ArrayList<Mcp.Prompts.Types.PromptMessage> messages { get; set; }

Methods

public Json.Node to_json ()
public GetPromptResult.from_json (Json.Node node) throws Error

Mcp.Prompts.Types.PromptMessage

Prompt message.

Constructor

public PromptMessage (string role, Mcp.Types.Common.ContentBlock content)

Properties

public string role { get; set; }
public Mcp.Types.Common.ContentBlock content { get; set; }

Methods

public Json.Node to_json ()
public PromptMessage.from_json (Json.Node node) throws Error

Usage Patterns

Server Initialization Pattern

public class MyMcpServer : GLib.Object {
    private Mcp.Core.Server server;
    
    public MyMcpServer () {
        // 1. Create server info
        var server_info = new Mcp.Types.Protocol.ServerInfo (
            "my-server",
            "1.0.0",
            "Description of my server"
        );
        
        // 2. Configure capabilities
        var capabilities = new Mcp.Types.Protocol.ServerCapabilities ();
        capabilities.logging = true;
        
        // 3. Create server
        server = new Mcp.Core.Server (server_info, capabilities);
        
        // 4. Set up components
        setup_components ();
    }
    
    private void setup_components () {
        // Register resources, tools, and prompts
    }
    
    public async int run () {
        // Start server and run main loop
        yield server.start ();
        new MainLoop ().run ();
        return 0;
    }
}

Resource Provider Pattern

public class MyResourceProvider : Mcp.Resources.BaseProvider {
    private HashTable<string, string> storage;
    
    public MyResourceProvider () {
        storage = new HashTable<string, string> (str_hash, str_equal);
        initialize_data ();
    }
    
    public override async Gee.ArrayList<Mcp.Resources.Types.Resource> list_resources (string? cursor) throws Error {
        var resources = new Gee.ArrayList<Mcp.Resources.Types.Resource> ();
        
        foreach (var entry in storage.get_keys ()) {
            var resource = new Mcp.Resources.Types.Resource (entry, entry);
            resource.mime_type = guess_mime_type (entry);
            resources.add (resource);
        }
        
        return resources;
    }
    
    public override async Mcp.Types.Common.ResourceContents read_resource (string uri) throws Error {
        if (!storage.contains (uri)) {
            throw new Mcp.Core.Error.NOT_FOUND ("Resource not found");
        }
        
        return new Mcp.Types.Common.TextResourceContents (uri, storage[uri]);
    }
}

Tool Executor Pattern

public class MyTool : Mcp.Tools.BaseExecutor {
    public MyTool () {
        // Define input schema using Variant
        var input_schema = Mcp.Types.VariantUtils.new_dict_builder ();
        input_schema.add ("{sv}", "type", new Variant.string ("object"));
        
        var properties = Mcp.Types.VariantUtils.new_dict_builder ();
        var param = Mcp.Types.VariantUtils.new_dict_builder ();
        param.add ("{sv}", "type", new Variant.string ("string"));
        param.add ("{sv}", "description", new Variant.string ("Parameter description"));
        properties.add ("{sv}", "param", param.end ());
        
        var required = new VariantBuilder (new VariantType ("as"));
        required.add_value ("s", "param");
        input_schema.add ("{sv}", "properties", properties.end ());
        input_schema.add ("{sv}", "required", required.end ());
        
        var definition = new Mcp.Tools.Types.ToolDefinition ("my_tool", input_schema.end ());
        definition.description = "Description of my tool";
        
        base (definition);
    }
    
    protected override async Mcp.Tools.Types.CallToolResult do_execute (Variant arguments) throws Error {
        string param = get_string_arg (arguments, "param");
        
        // Process input
        string result = process_parameter (param);
        
        return create_text_result ("Result: %s".printf (result));
    }
    
    private string process_parameter (string input) {
        // Custom processing logic
        return input.up ();
    }
}

Prompt Template Pattern

public class MyPrompt : Mcp.Prompts.BaseTemplate {
    public MyPrompt () {
        var arguments = new Gee.ArrayList<Mcp.Prompts.Types.PromptArgument> ();
        
        var topic_arg = new Mcp.Prompts.Types.PromptArgument ("topic");
        topic_arg.description = "The topic to generate content for";
        topic_arg.required = true;
        arguments.add (topic_arg);
        
        var style_arg = new Mcp.Prompts.Types.PromptArgument ("style");
        style_arg.description = "Writing style";
        arguments.add (style_arg);
        
        base ("my_prompt", "My Prompt", "Description of my prompt", arguments);
    }
    
    protected override async Mcp.Prompts.Types.GetPromptResult do_render (Variant arguments) throws Error {
        string topic = Mcp.Types.VariantUtils.get_string (arguments, "topic");
        string style = Mcp.Types.VariantUtils.get_string (arguments, "style", "neutral");
        
        string template = """Generate %s content about %s.""".printf (style, topic);
        
        var content = new Mcp.Types.Common.TextContent (template);
        var message = new Mcp.Prompts.Types.PromptMessage ("user", content);
        var messages = new Gee.ArrayList<Mcp.Prompts.Types.PromptMessage> ();
        messages.add (message);
        
        return new Mcp.Prompts.Types.GetPromptResult (messages);
    }
}

JSON-RPC Protocol Implementation

The library implements the JSON-RPC 2.0 specification for MCP:

Request Format

{
  "jsonrpc": "2.0",
  "id": "unique-request-id",
  "method": "tools/list",
  "params": {}
}

Response Format

{
  "jsonrpc": "2.0",
  "id": "unique-request-id",
  "result": {
    "tools": [...]
  }
}

Error Response Format

{
  "jsonrpc": "2.0",
  "id": "unique-request-id",
  "error": {
    "code": -32602,
    "message": "Invalid params",
    "data": null
  }
}

Notification Format

{
  "jsonrpc": "2.0",
  "method": "notifications/resources/list_changed",
  "params": {}
}

Type System

The library uses Vala's type system for compile-time safety:

Primitives

• string - Text data
• int/int64 - Integer values
• double - Floating-point values
• bool - Boolean values

Collections

• Gee.ArrayList<T> - Dynamic arrays
• HashTable<K,V> - Key-value maps
• Json.Object - JSON objects
• Json.Array - JSON arrays
• Json.Node - Generic JSON value

Null Safety

Optional types use ? suffix:

public string? description { get; set; }  // Can be null
public string name { get; set; }           // Cannot be null

Error Handling

Error Hierarchy

Mcp.Core.McpError
├── PARSE_ERROR (-32700)
├── INVALID_REQUEST (-32600)
├── METHOD_NOT_FOUND (-32601)
├── INVALID_PARAMS (-32602)
├── INTERNAL_ERROR (-32603)
├── RESOURCE_NOT_FOUND (-32604)
└── TRANSPORT_ERROR (-32605)

Error Handling Pattern

try {
    // MCP operation
} catch (Mcp.Core.Error e) {
    // Handle MCP-specific errors
    stderr.printf ("MCP Error [%d]: %s\n", e.code, e.message);
} catch (GLib.Error e) {
    // Handle other errors
    stderr.printf ("GLib Error: %s\n", e.message);
}

Best Practices

1. Always validate input before processing
2. Use structured results for complex data
3. Handle errors gracefully and provide meaningful messages
4. Follow async patterns for I/O operations
5. Document custom components with Valadoc comments
6. Use appropriate MIME types for resources
7. Implement subscription notifications for dynamic content
8. Test with real MCP clients to verify compatibility

Version Compatibility

The library follows MCP specification version "2025-11-25" and maintains backward compatibility where possible. Future versions will be additive and non-breaking.

Migration Guide

From Custom JSON-RPC to Jsonrpc

If you were using custom JSON-RPC handling in previous versions:

1. No API changes required - The public API remains the same
2. Internal improvements - Better error handling and IO reliability
3. Performance benefits - Optimized JSON parsing and message handling
4. Standard compliance - Full JSON-RPC 2.0 compliance through jsonrpc-glib-1.0

The migration is transparent for existing code using the library's public API.