Clinical Trials MCP Server

Instructions

Implementation Reference

• src/index.ts:1317-1383 (handler)

  The handler function `handleSearchByIntervention` executes the logic to fetch clinical trials by intervention using the ClinicalTrials.gov API.

  private async handleSearchByIntervention(args: any) {
    if (!args?.intervention) {
      throw new McpError(
        ErrorCode.InvalidParams,
        "Intervention parameter is required"
      );
    }
  
    const params: any = {
      format: "json",
      pageSize: args?.pageSize || 10,
      "query.intr": args.intervention,
    };
  
    if (args?.interventionType) {
      params["filter.interventionType"] = args.interventionType;
    }
  
    if (args?.phase) {
      params["filter.phase"] = args.phase;
    }
  
    try {
      const response: AxiosResponse<StudySearchResponse> =
        await this.axiosInstance.get("/studies", { params });
  
      const studies = response.data.studies || [];
      const results = studies.map((study) => this.formatStudySummary(study));
  
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify(
              {
                searchCriteria: {
                  intervention: args.intervention,
                  interventionType: args.interventionType,
                  phase: args.phase,
                },
                totalCount: response.data.totalCount || 0,
                resultsShown: results.length,
                studies: results,
              },
              null,
              2
            ),
          },
        ],
      };
    } catch (error) {
      if (axios.isAxiosError(error)) {
        return {
          content: [
            {
              type: "text",
              text: `Clinical Trials API error: ${
                error.response?.data?.message || error.message
              }`,
            },
          ],
          isError: true,
        };
      }
      throw error;
    }
  }

• src/index.ts:328-366 (registration)

  The tool `search_by_intervention` is registered in the list of tools with its schema definition.

    name: "search_by_intervention",
    description:
      "Search clinical trials by intervention or treatment type",
    inputSchema: {
      type: "object",
      properties: {
        intervention: {
          type: "string",
          description: "Intervention, drug, device, or treatment name",
          minLength: 2,
        },
        interventionType: {
          type: "string",
          description: "Type of intervention",
          enum: [
            "DRUG",
            "DEVICE",
            "BIOLOGICAL",
            "PROCEDURE",
            "BEHAVIORAL",
            "OTHER",
          ],
        },
        phase: {
          type: "string",
          description: "Study phase filter",
          enum: ["PHASE1", "PHASE2", "PHASE3", "PHASE4", "NA"],
        },
        pageSize: {
          type: "number",
          description:
            "Number of results to return (default 10, max 100)",
          minimum: 1,
          maximum: 100,
        },
      },
      required: ["intervention"],
    },
  },