Model Context Protocol Ontology
The Model Context Protocol (MCP) Ontology defines concepts and relationships for describing interactions between AI language models and external context providers.
Server
An MCP server implementation that provides resources, tools, and prompts to clients
Client
An MCP client implementation that connects to servers and facilitates interaction with language models
Resource
A resource accessible via MCP, typically containing contextual information for language models
Tool
A tool callable via MCP that provides specific functionality to language models
Prompt
A prompt template provided by an MCP server that structures interactions with language models
Message
A message exchanged in an MCP conversation between users and language models
Content
Content contained within an MCP message
Text Content
Textual content within an MCP message
Image Content
Image content within an MCP message
Role
Role of a participant (user or assistant) in MCP communication
Capability
A capability supported by an MCP implementation
has capability
Relates an MCP implementation to its supported capabilities
provides resource
Relates a server to a resource it makes available
provides tool
Relates a server to a tool it makes available
provides prompt
Relates a server to a prompt template it makes available
has content
Relates a message to its content
has role
Relates a message to the role of its sender