Elicitation

Elicitation allows the server to request additional input from the user during tool execution. It replaces the deprecated Sampling mechanism (SEP-2577).

Form Mode

Requests structured user input via a JSON Schema form:

ElicitRequestParams params;
params.message = "Please provide your shipping address";
params.requested_schema = JsonValue::Parse(R"({
    "type": "object",
    "properties": {
        "street": {"type": "string"},
        "city": {"type": "string"},
        "zip": {"type": "string"}
    },
    "required": ["street", "city", "zip"]
})");

auto future = server->Elicit(params);
auto result = future.get();
if (result.content) {
    auto street = (*result.content)["street"];
}

Elicitation Result

ElicitResult extends Result with:

Field	Type	Description
action	string	"accept", "decline", or "cancel"
content	optional<JsonValue>	Submitted form data (present on accept)

The inherited result_type (Complete or InputRequired) indicates whether the input was fulfilled or is still pending.

Typed Helper

ElicitResultTyped<T> is a user-side convenience struct for wrapping a deserialized result:

struct AddressForm {
    std::string street;
    std::string city;
    std::string zip_code;
};

ElicitResult raw = future.get();
ElicitResultTyped<AddressForm> typed;
if (raw.content) {
    typed.action = "accept";
    typed.content = AddressForm{
        (*raw.content)["street"].GetString(),
        (*raw.content)["city"].GetString(),
        (*raw.content)["zip_code"].GetString()
    };
}

if (typed.is_accepted() && typed.content) {
    auto& addr = *typed.content;
    // ...
}

ElicitResultTyped<T> members:

Member	Type	Description
action	string	"accept", "decline", or "cancel" (default)
content	optional<T>	Deserialized values (present on accept)
is_accepted()	bool	Returns true when action == "accept"

Note: ElicitResultTyped<T> is not returned by any API — construct it manually from a raw ElicitResult.