cmcp_server.h File Reference

Server API: lifecycle, tool/resource/prompt registry, dispatch, notifications. More...

#include "cmcp_json.h"
#include "cmcp_types.h"
#include "cmcp_transport.h"

Go to the source code of this file.

Data Structures
struct	cmcp_tool_t
struct	cmcp_resource_t
struct	cmcp_prompt_t

Typedefs
typedef struct cmcp_server	cmcp_server_t
typedef struct cmcp_handler_ctx	cmcp_handler_ctx_t
typedef int(*	cmcp_tool_handler_fn) (const cmcp_json_t *arguments, void *userdata, cmcp_handler_ctx_t *hctx, cmcp_json_t **out_content, int *out_is_error)
typedef int(*	cmcp_resource_read_fn) (const char *uri, void *userdata, cmcp_handler_ctx_t *hctx, cmcp_json_t **out_contents, int *out_is_error)
typedef int(*	cmcp_prompt_handler_fn) (const cmcp_json_t *arguments, void *userdata, cmcp_handler_ctx_t *hctx, cmcp_json_t **out_messages)

Functions
cmcp_server_t *	cmcp_server_new (const char *name, const char *version)
void	cmcp_server_free (cmcp_server_t *s)
void	cmcp_server_set_capabilities (cmcp_server_t *s, const cmcp_server_capabilities_t *caps)
int	cmcp_server_set_description (cmcp_server_t *s, const char *description)
const char *	cmcp_server_client_description (const cmcp_server_t *s)
int	cmcp_handler_cancelled (const cmcp_handler_ctx_t *hctx)
int	cmcp_handler_progress (cmcp_handler_ctx_t *hctx, double progress, double total, const char *message)
const char *	cmcp_handler_get_header (const cmcp_handler_ctx_t *hctx, const char *name)
void	cmcp_handler_set_structured (cmcp_handler_ctx_t *hctx, cmcp_json_t *value)
int	cmcp_server_add_tool (cmcp_server_t *s, const cmcp_tool_t *tool)
cmcp_json_t *	cmcp_tool_text_content (const char *text)
cmcp_json_t *	cmcp_tool_resource_link_content (const char *uri, const char *name, const char *description, const char *mime_type)
int	cmcp_server_add_resource (cmcp_server_t *s, const cmcp_resource_t *r)
cmcp_json_t *	cmcp_resource_text_contents (const char *uri, const char *mime_type, const char *text)
int	cmcp_server_add_prompt (cmcp_server_t *s, const cmcp_prompt_t *p)
cmcp_json_t *	cmcp_prompt_text_messages (const char *role, const char *text)
int	cmcp_server_run (cmcp_server_t *s, cmcp_transport_t *t)
int	cmcp_server_run_stdio (cmcp_server_t *s)
const cmcp_client_capabilities_t *	cmcp_server_client_caps (const cmcp_server_t *s)
const char *	cmcp_server_client_name (const cmcp_server_t *s)
const char *	cmcp_server_client_version (const cmcp_server_t *s)
int	cmcp_server_notify (cmcp_server_t *s, const char *method, cmcp_json_t *params)
int	cmcp_server_notify_tools_changed (cmcp_server_t *s)
int	cmcp_server_notify_resources_changed (cmcp_server_t *s)
int	cmcp_server_notify_prompts_changed (cmcp_server_t *s)
int	cmcp_server_notify_resource_updated (cmcp_server_t *s, const char *uri)
int	cmcp_server_log (cmcp_server_t *s, cmcp_log_level_t level, const char *logger, cmcp_json_t *data)
int	cmcp_server_send_request (cmcp_server_t *s, cmcp_handler_ctx_t *hctx, const char *method, cmcp_json_t *params, cmcp_rpc_message_t *out_response)
int	cmcp_handler_elicit (cmcp_handler_ctx_t *hctx, const char *message, cmcp_json_t *requested_schema, cmcp_json_t **out_result)
int	cmcp_handler_elicit_url (cmcp_handler_ctx_t *hctx, const char *message, const char *url, cmcp_json_t **out_result)

Detailed Description

Server API: lifecycle, tool/resource/prompt registry, dispatch, notifications.

A cmcp_server_t owns:

• The registries for tools, resources, and prompts.
• The dispatch loop driving the worker pool.
• The lifecycle of a single MCP session (handshake → operate → teardown) against one transport.

Capabilities (tools, resources, prompts) are auto-advertised when at least one matching primitive is registered. Server-initiated notifications go via cmcp_server_notify (generic) and the capability-gated convenience wrappers. Handlers run on a small worker-pool thread; they get a per-call cmcp_handler_ctx_t for cooperative cancellation, progress reporting, and (in 2025-11-25) elicitation/create round-trips back to the host.

See examples/echo-server.c for a complete minimal server and tools/filesystem-mcp/main.c for a production-shaped one.

Definition in file cmcp_server.h.

Typedef Documentation

cmcp_server_t

typedef struct cmcp_server cmcp_server_t

Definition at line 31 of file cmcp_server.h.

cmcp_handler_ctx_t

typedef struct cmcp_handler_ctx cmcp_handler_ctx_t

Definition at line 67 of file cmcp_server.h.

cmcp_tool_handler_fn

typedef int(* cmcp_tool_handler_fn) (const cmcp_json_t *arguments, void *userdata, cmcp_handler_ctx_t *hctx, cmcp_json_t **out_content, int *out_is_error)

Definition at line 144 of file cmcp_server.h.

cmcp_resource_read_fn

typedef int(* cmcp_resource_read_fn) (const char *uri, void *userdata, cmcp_handler_ctx_t *hctx, cmcp_json_t **out_contents, int *out_is_error)

Definition at line 262 of file cmcp_server.h.

cmcp_prompt_handler_fn

typedef int(* cmcp_prompt_handler_fn) (const cmcp_json_t *arguments, void *userdata, cmcp_handler_ctx_t *hctx, cmcp_json_t **out_messages)

Definition at line 315 of file cmcp_server.h.

Function Documentation

cmcp_server_new()

cmcp_server_t * cmcp_server_new	(	const char *	name,
		const char *	version
	)

cmcp_server_free()

void cmcp_server_free

(

cmcp_server_t *

s

)

cmcp_server_set_capabilities()

void cmcp_server_set_capabilities	(	cmcp_server_t *	s,
		const cmcp_server_capabilities_t *	caps
	)

cmcp_server_set_description()

int cmcp_server_set_description	(	cmcp_server_t *	s,
		const char *	description
	)

cmcp_server_client_description()

const char * cmcp_server_client_description

(

const cmcp_server_t *

s

)

cmcp_handler_cancelled()

int cmcp_handler_cancelled

(

const cmcp_handler_ctx_t *

hctx

)

cmcp_handler_progress()

int cmcp_handler_progress	(	cmcp_handler_ctx_t *	hctx,
		double	progress,
		double	total,
		const char *	message
	)

cmcp_handler_get_header()

const char * cmcp_handler_get_header	(	const cmcp_handler_ctx_t *	hctx,
		const char *	name
	)

cmcp_handler_set_structured()

void cmcp_handler_set_structured	(	cmcp_handler_ctx_t *	hctx,
		cmcp_json_t *	value
	)

cmcp_server_add_tool()

int cmcp_server_add_tool	(	cmcp_server_t *	s,
		const cmcp_tool_t *	tool
	)

cmcp_tool_text_content()

cmcp_json_t * cmcp_tool_text_content

(

const char *

text

)

cmcp_tool_resource_link_content()

cmcp_json_t * cmcp_tool_resource_link_content	(	const char *	uri,
		const char *	name,
		const char *	description,
		const char *	mime_type
	)

cmcp_server_add_resource()

int cmcp_server_add_resource	(	cmcp_server_t *	s,
		const cmcp_resource_t *	r
	)

cmcp_resource_text_contents()

cmcp_json_t * cmcp_resource_text_contents	(	const char *	uri,
		const char *	mime_type,
		const char *	text
	)

cmcp_server_add_prompt()

int cmcp_server_add_prompt	(	cmcp_server_t *	s,
		const cmcp_prompt_t *	p
	)

cmcp_prompt_text_messages()

cmcp_json_t * cmcp_prompt_text_messages	(	const char *	role,
		const char *	text
	)

cmcp_server_run()

int cmcp_server_run	(	cmcp_server_t *	s,
		cmcp_transport_t *	t
	)

cmcp_server_run_stdio()

int cmcp_server_run_stdio

(

cmcp_server_t *

s

)

cmcp_server_client_caps()

const cmcp_client_capabilities_t * cmcp_server_client_caps

(

const cmcp_server_t *

s

)

cmcp_server_client_name()

const char * cmcp_server_client_name

(

const cmcp_server_t *

s

)

cmcp_server_client_version()

const char * cmcp_server_client_version

(

const cmcp_server_t *

s

)

cmcp_server_notify()

int cmcp_server_notify	(	cmcp_server_t *	s,
		const char *	method,
		cmcp_json_t *	params
	)

cmcp_server_notify_tools_changed()

int cmcp_server_notify_tools_changed

(

cmcp_server_t *

s

)

cmcp_server_notify_resources_changed()

int cmcp_server_notify_resources_changed

(

cmcp_server_t *

s

)

cmcp_server_notify_prompts_changed()

int cmcp_server_notify_prompts_changed

(

cmcp_server_t *

s

)

cmcp_server_notify_resource_updated()

int cmcp_server_notify_resource_updated	(	cmcp_server_t *	s,
		const char *	uri
	)

cmcp_server_log()

int cmcp_server_log	(	cmcp_server_t *	s,
		cmcp_log_level_t	level,
		const char *	logger,
		cmcp_json_t *	data
	)

cmcp_server_send_request()

int cmcp_server_send_request	(	cmcp_server_t *	s,
		cmcp_handler_ctx_t *	hctx,
		const char *	method,
		cmcp_json_t *	params,
		cmcp_rpc_message_t *	out_response
	)

cmcp_handler_elicit()

int cmcp_handler_elicit	(	cmcp_handler_ctx_t *	hctx,
		const char *	message,
		cmcp_json_t *	requested_schema,
		cmcp_json_t **	out_result
	)

cmcp_handler_elicit_url()

int cmcp_handler_elicit_url	(	cmcp_handler_ctx_t *	hctx,
		const char *	message,
		const char *	url,
		cmcp_json_t **	out_result
	)