Architecture overview changeddocs/2025-11-25/learn/architecture
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55Because MCP SDKs abstract away many concerns, most developers will likely find the [data layer protocol](#data-layer-protocol) section to be the most useful. It discusses how MCP servers can provide context to an AI application.
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7For specific implementation details, please refer to the documentation for your [language-specific SDK](/docs/2025-11-25/sdk).
7For specific implementation details, please refer to the documentation for your [language-specific SDK](/docs/2025-11-25/sdk.md).
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99## Scope
1010
1111The Model Context Protocol includes the following projects:
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13* [MCP Specification](https://modelcontextprotocol.io/specification/latest): A specification of MCP that outlines the implementation requirements for clients and servers.
14* [MCP SDKs](/docs/2025-11-25/sdk): SDKs for different programming languages that implement MCP.
13* [MCP Specification](https://modelcontextprotocol.io/specification/latest.md): A specification of MCP that outlines the implementation requirements for clients and servers.
14* [MCP SDKs](/docs/2025-11-25/sdk.md): SDKs for different programming languages that implement MCP.
1515* **MCP Development Tools**: Tools for developing MCP servers and clients, including the [MCP Inspector](https://github.com/modelcontextprotocol/inspector)
1616* [MCP Reference Server Implementations](https://github.com/modelcontextprotocol/servers): Reference implementations of MCP servers.
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105105#### Lifecycle management
106106
107MCP is a stateful protocol (A subset of MCP can be made stateless using the Streamable HTTP transport) that requires lifecycle management. The purpose of lifecycle management is to negotiate the capabilities (Features and operations that a client or server supports, such as tools, resources, or prompts) that both client and server support. Detailed information can be found in the [specification](/specification/2025-11-25/basic/lifecycle), and the [example](#example) showcases the initialization sequence.
107MCP is a stateful protocol (A subset of MCP can be made stateless using the Streamable HTTP transport) that requires lifecycle management. The purpose of lifecycle management is to negotiate the capabilities (Features and operations that a client or server supports, such as tools, resources, or prompts) that both client and server support. Detailed information can be found in the [specification](/specification/2025-11-25/basic/lifecycle.md), and the [example](#example) showcases the initialization sequence.
108108
109109#### Primitives
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122122As a concrete example, consider an MCP server that provides context about a database. It can expose tools for querying the database, a resource that contains the schema of the database, and a prompt that includes few-shot examples for interacting with the tools.
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124For more details about server primitives see [server concepts](./server-concepts).
124For more details about server primitives see [server concepts](/docs/2025-11-25/learn/server-concepts.md).
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126126MCP also defines primitives that *clients* can expose. These primitives allow MCP server authors to build richer interactions.
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129129* **Elicitation**: Allows servers to request additional information from users. This is useful when server authors want to get more information from the user, or ask for confirmation of an action. They can use the `elicitation/create` method to request additional information from the user.
130130* **Logging**: Enables servers to send log messages to clients for debugging and monitoring purposes.
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132For more details about client primitives see [client concepts](./client-concepts).
132For more details about client primitives see [client concepts](/docs/2025-11-25/learn/client-concepts.md).
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134134Besides server and client primitives, the protocol offers cross-cutting utility primitives that augment how requests are executed:
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