@modelcontextprotocol/server-everything/dist/tools/trigger-elicitation-request.js

MCP server that exercises all the features of the MCP protocol

// The `trigger-elicitation-request` tool: asks the user to fill in a form
// that exercises every field type form-mode elicitation supports, and
// summarizes the answer.
//
// Written once for both protocol eras with a multi-round-trip request
// (#4852): the first call returns `input_required` carrying an
// `elicitation/create` request, the client shows the form and retries with
// the answer, and the retry summarizes it. A 2026-07-28 client does that
// in-band; for a 2025-era client the SDK's legacy shim sends a real
// `elicitation/create` request and re-enters the handler with the answer.
import { inputRequired, inputResponse, } from "@modelcontextprotocol/server";
import { TOOL_ICONS } from "../server/icons.js";
// Tool configuration
const name = "trigger-elicitation-request";
const config = {
    title: "Trigger Elicitation Request Tool",
    description: "Trigger a Request from the Server for User Elicitation",
    inputSchema: {},
    icons: TOOL_ICONS,
    annotations: {
        readOnlyHint: false,
        destructiveHint: false,
        idempotentHint: false,
        openWorldHint: false,
    },
};
/** The form's fields: one of each type form-mode elicitation supports. */
const properties = {
    name: {
        title: "String",
        type: "string",
        description: "Your full, legal name",
    },
    check: {
        title: "Boolean",
        type: "boolean",
        description: "Agree to the terms and conditions",
    },
    firstLine: {
        title: "String with default",
        type: "string",
        description: "Favorite first line of a story",
        default: "It was a dark and stormy night.",
    },
    email: {
        title: "String with email format",
        type: "string",
        format: "email",
        description: "Your email address (will be verified, and never shared with anyone else)",
    },
    homepage: {
        type: "string",
        format: "uri",
        title: "String with uri format",
        description: "Portfolio / personal website",
    },
    birthdate: {
        title: "String with date format",
        type: "string",
        format: "date",
        description: "Your date of birth",
    },
    integer: {
        title: "Integer",
        type: "integer",
        description: "Your favorite integer (do not give us your phone number, pin, or other sensitive info)",
        minimum: 1,
        maximum: 100,
        default: 42,
    },
    number: {
        title: "Number in range 1-1000",
        type: "number",
        description: "Favorite number (there are no wrong answers)",
        minimum: 0,
        maximum: 1000,
        default: 3.14,
    },
    untitledSingleSelectEnum: {
        type: "string",
        title: "Untitled Single Select Enum",
        description: "Choose your favorite friend",
        enum: ["Monica", "Rachel", "Joey", "Chandler", "Ross", "Phoebe"],
        default: "Monica",
    },
    untitledMultipleSelectEnum: {
        type: "array",
        title: "Untitled Multiple Select Enum",
        description: "Choose your favorite instruments",
        minItems: 1,
        maxItems: 3,
        items: {
            type: "string",
            enum: ["Guitar", "Piano", "Violin", "Drums", "Bass"],
        },
        default: ["Guitar"],
    },
    titledSingleSelectEnum: {
        type: "string",
        title: "Titled Single Select Enum",
        description: "Choose your favorite hero",
        oneOf: [
            { const: "hero-1", title: "Superman" },
            { const: "hero-2", title: "Green Lantern" },
            { const: "hero-3", title: "Wonder Woman" },
        ],
        default: "hero-1",
    },
    titledMultipleSelectEnum: {
        type: "array",
        title: "Titled Multiple Select Enum",
        description: "Choose your favorite types of fish",
        minItems: 1,
        maxItems: 3,
        items: {
            anyOf: [
                { const: "fish-1", title: "Tuna" },
                { const: "fish-2", title: "Salmon" },
                { const: "fish-3", title: "Trout" },
            ],
        },
        default: ["fish-1"],
    },
    legacyTitledEnum: {
        type: "string",
        title: "Legacy Titled Single Select Enum",
        description: "Choose your favorite type of pet",
        enum: ["pet-1", "pet-2", "pet-3", "pet-4", "pet-5"],
        enumNames: ["Cats", "Dogs", "Birds", "Fish", "Reptiles"],
        default: "pet-1",
    },
};
/** The form, as the elicitation request carries it. */
const requestedSchema = {
    type: "object",
    properties,
    required: ["name"],
};
/**
 * The label each field gets in the summary of an accepted form. Keyed by the
 * form's own field names, so a field added to or removed from the form fails
 * to compile until its label follows, and the summary cannot drift from the
 * form again (#5209).
 */
const summaryLabels = {
    name: "Name",
    check: "Agreed to terms",
    firstLine: "Favorite first line",
    email: "Email",
    homepage: "Homepage",
    birthdate: "Birthdate",
    integer: "Favorite integer",
    number: "Favorite number",
    untitledSingleSelectEnum: "Favorite friend",
    untitledMultipleSelectEnum: "Favorite instruments",
    titledSingleSelectEnum: "Favorite hero",
    titledMultipleSelectEnum: "Favorite fish",
    legacyTitledEnum: "Favorite pet",
};
/**
 * One summary line per form field the user answered, in the form's order.
 * A field the form does not define is left out, whatever the client sent.
 */
const summarize = (userData) => Object.keys(properties)
    .filter((field) => userData[field] !== undefined)
    .map((field) => {
    const value = userData[field];
    const shown = Array.isArray(value) ? value.join(", ") : String(value);
    return `- ${summaryLabels[field]}: ${shown}`;
});
/**
 * Registers the 'trigger-elicitation-request' tool.
 *
 * The tool needs a client that supports form-mode elicitation. On a 2025-era
 * connection the server factory registers it only for a client that declared
 * `elicitation.form`, or an `elicitation` object with neither `form` nor
 * `url`, which the spec treats as form mode for backwards compatibility; a
 * client that declared only `elicitation.url` does not get it (#4985). On
 * 2026-07-28 the SDK refuses the embedded request (-32021) of a client whose
 * request did not declare form-mode elicitation.
 *
 * The first round sends the form. The retry reads the user's response, which
 * may be acceptance with content, decline, or cancellation of the dialog, and
 * returns a structured summary with the raw result for debugging.
 *
 * @param {McpServer} server - The McpServer instance where the tool will be registered.
 */
export const registerTriggerElicitationRequestTool = (server) => {
    server.registerTool(name, config, async (_args, ctx) => {
        const answer = inputResponse(ctx.mcpReq.inputResponses, "form");
        // First round: show the user the form
        if (answer.kind !== "elicit") {
            return inputRequired({
                inputRequests: {
                    form: inputRequired.elicit({
                        message: "Please provide inputs for the following fields:",
                        requestedSchema,
                    }),
                },
            });
        }
        // The answer as the client sent it, for the debugging output
        const rawResult = {
            action: answer.action,
            ...(answer.content !== undefined && { content: answer.content }),
        };
        // Handle different response actions
        const content = [];
        if (answer.action === "accept" && answer.content) {
            content.push({
                type: "text",
                text: `✅ User provided the requested information!`,
            });
            // Only access answer.content when action is accept
            const lines = summarize(answer.content);
            content.push({
                type: "text",
                text: `User inputs:\n${lines.join("\n")}`,
            });
        }
        else if (answer.action === "decline") {
            content.push({
                type: "text",
                text: `❌ User declined to provide the requested information.`,
            });
        }
        else if (answer.action === "cancel") {
            content.push({
                type: "text",
                text: `⚠️ User cancelled the elicitation dialog.`,
            });
        }
        // Include raw result for debugging
        content.push({
            type: "text",
            text: `\nRaw result: ${JSON.stringify(rawResult, null, 2)}`,
        });
        return { content };
    });
};