Declare the client capabilities a registered tool's handler requires.
On the draft protocol (which carries the caller's clientCapabilities
per-request in _meta), a tools/call for this tool is rejected up front
with a -32003MissingRequiredClientCapabilityError — whose
data.requiredCapabilities is a ClientCapabilities object listing
exactly the unmet capabilities — when the request's declared capabilities
do not cover caps (draft basic/lifecycle: "A server MUST NOT rely on
capabilities the client has not declared"). On the stateful 2025-era
protocols the gate uses the session capabilities negotiated at
initialize. Passing a default-constructed ClientCapabilities clears the
requirement. Returns false if no tool with name is registered.
Declare the client capabilities a registered tool's handler requires.
On the draft protocol (which carries the caller's clientCapabilities per-request in _meta), a tools/call for this tool is rejected up front with a -32003 MissingRequiredClientCapabilityError — whose data.requiredCapabilities is a ClientCapabilities object listing exactly the unmet capabilities — when the request's declared capabilities do not cover caps (draft basic/lifecycle: "A server MUST NOT rely on capabilities the client has not declared"). On the stateful 2025-era protocols the gate uses the session capabilities negotiated at initialize. Passing a default-constructed ClientCapabilities clears the requirement. Returns false if no tool with name is registered.