MCP Client Capabilities
Industry Definition Set • Entity Resolution Path: /glossary/mcp-client-capabilities
Quick Answer / TL;DR
The set of features a client declares it supports during MCP initialization, such as roots, sampling, or elicitation.
Key Takeaways
- Declared during the initialize handshake.
- Tells the server what client-side features are available.
- Includes roots, sampling, elicitation, and experimental features.
- Server must not use features the client did not declare.
Definitive Statement: The set of features a client declares it supports during MCP initialization, such as roots, sampling, or elicitation.
Technical Context & Protocol Usage
- Detailed Explanation
- During the initialize handshake, the client sends a `capabilities` object describing what it can do. This might include `roots` (filesystem boundary enforcement), `sampling` (client-side LLM inference), or `elicitation` (rendering forms for user input). The server uses this information to decide which features it can safely use.
Format & Payload Metadata
Format: JSON object in the initialize request params
Latency: Evaluated once at session start
Real-World Implementation Use Case
Claude Desktop declares `roots` and `sampling` capabilities, so an MCP filesystem server knows it can enforce root boundaries and request client-side sampling.
Cite This Page
MLA Style:
MCPserver.in Engineering. "MCP Client Capabilities." MCPserver.in Knowledge Hub, 20 July 2026, mcpserver.in/glossary/mcp-client-capabilities.
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