Medplum MCP Server

Instructions

Implementation Reference

• src/tools/medicationRequestUtils.ts:70-111 (handler)

  The async handler function that validates input, constructs a FHIR MedicationRequest resource, and creates it via the Medplum client.

  export async function createMedicationRequest(args: CreateMedicationRequestArgs): Promise<MedicationRequest> {
    await ensureAuthenticated();
  
    if (!args.status) {
      throw new Error('MedicationRequest status is required.');
    }
    if (!args.intent) {
      throw new Error('MedicationRequest intent is required.');
    }
    if (!args.medicationCodeableConcept) { // Add || !args.medicationReference if that's supported
      throw new Error('Medication (medicationCodeableConcept or medicationReference) is required.');
    }
    if (!args.subjectId) {
      throw new Error('Subject (Patient ID) is required to create a MedicationRequest.');
    }
  
    const medicationRequestResource: MedicationRequest = {
      resourceType: 'MedicationRequest',
      status: args.status,
      intent: args.intent,
      medicationCodeableConcept: args.medicationCodeableConcept,
      // medicationReference: args.medicationReference,
      subject: { reference: `Patient/${args.subjectId}` },
      authoredOn: args.authoredOn || new Date().toISOString(),
      dosageInstruction: args.dosageInstruction,
    };
  
    if (args.encounterId) {
      medicationRequestResource.encounter = { reference: `Encounter/${args.encounterId}` };
    }
    if (args.requesterId) {
      medicationRequestResource.requester = { reference: `Practitioner/${args.requesterId}` };
    }
    if (args.note) {
      medicationRequestResource.note = [{ text: args.note }];
    }
    if (args.identifier) {
      medicationRequestResource.identifier = [{ system: args.identifier.system, value: args.identifier.value }];
    }
  
    return medplum.createResource<MedicationRequest>(medicationRequestResource);
  }

• src/tools/medicationRequestUtils.ts:15-28 (schema)

  TypeScript interface defining the input parameters expected by the createMedicationRequest handler.

  export interface CreateMedicationRequestArgs {
    status: MedicationRequest['status'];
    intent: MedicationRequest['intent'];
    medicationCodeableConcept?: CodeableConcept;
    // medicationReference?: Reference; // TODO: Add if direct reference to Medication resource is needed
    subjectId: string; // Convenience for Patient reference
    encounterId?: string; // Convenience for Encounter reference
    authoredOn?: string;
    requesterId?: string; // Convenience for Practitioner reference
    dosageInstruction?: Dosage[];
    note?: string;
    identifier?: { system?: string; value: string };
    // Add other relevant fields like dispenseRequest, category, priority, etc. as needed
  }

• src/index.ts:562-592 (schema)

  MCP tool schema defining the input validation for createMedicationRequest tool calls.

  {
    name: "createMedicationRequest",
    description: "Creates a new medication request (prescription). Requires patient ID, medication reference, and prescriber.",
    inputSchema: {
      type: "object",
      properties: {
        patientId: {
          type: "string",
          description: "The ID of the patient this prescription is for.",
        },
        medicationReference: {
          type: "string",
          description: "Reference to the medication being prescribed.",
        },
        practitionerId: {
          type: "string",
          description: "The ID of the practitioner prescribing the medication.",
        },
        status: {
          type: "string",
          description: "The status of the medication request.",
          enum: ["active", "on-hold", "cancelled", "completed", "entered-in-error", "stopped", "draft", "unknown"],
        },
        intent: {
          type: "string",
          description: "The intent of the medication request.",
          enum: ["proposal", "plan", "order", "original-order", "reflex-order", "filler-order", "instance-order", "option"],
        },
      },
      required: ["patientId", "medicationReference", "practitionerId", "status", "intent"],
    },

• src/index.ts:44-49 (registration)

  Import statement registering the createMedicationRequest function from medicationRequestUtils.

  import {
    createMedicationRequest,
    getMedicationRequestById,
    updateMedicationRequest,
    searchMedicationRequests,
  } from './tools/medicationRequestUtils.js';

• src/index.ts:972-972 (registration)

  Entry in toolMapping object that maps the tool name to its handler function for execution.

  createMedicationRequest,