MeSH MCP

Instructions

Implementation Reference

• src/mesh_mcp/server.py:344-422 (handler)

  The get_mesh_tree tool implementation, which retrieves the MeSH tree hierarchy for a given descriptor UI.

  @mcp.tool()
  def get_mesh_tree(descriptor: str) -> dict:
      """
      Retrieve the MeSH tree hierarchy for a descriptor: its tree numbers,
      the full name of each top-level category, and its immediate broader
      (parent) descriptors.
  
      Use this to understand where a heading sits within the MeSH hierarchy,
      helping to determine whether the heading is specific enough for the work
      or whether a broader heading would be more appropriate.
  
      MeSH tree number top-level categories:
        A  Anatomy
        B  Organisms
        C  Diseases
        D  Chemicals and Drugs
        E  Analytical, Diagnostic and Therapeutic Techniques and Equipment
        F  Psychiatry and Psychology
        G  Phenomena and Processes
        H  Disciplines and Occupations
        I  Anthropology, Education, Sociology and Social Phenomena
        J  Technology, Industry, and Agriculture
        K  Humanities
        L  Information Science
        M  Named Groups
        N  Health Care
        V  Publication Characteristics
        Z  Geographicals
  
      Parameters
      ----------
      descriptor : str
          The MeSH UI code (e.g. "D003920") or full URI returned by search_mesh.
  
      Returns
      -------
      dict
          Contains:
            - ui          : MeSH unique identifier
            - label       : Preferred heading label
            - treeNumbers : List of tree number strings
            - categories  : List of {letter, name} dicts for top-level categories
            - broader     : List of {label, ui} dicts for parent descriptors
      """
      _CATEGORY_NAMES = {
          "A": "Anatomy",
          "B": "Organisms",
          "C": "Diseases",
          "D": "Chemicals and Drugs",
          "E": "Analytical, Diagnostic and Therapeutic Techniques and Equipment",
          "F": "Psychiatry and Psychology",
          "G": "Phenomena and Processes",
          "H": "Disciplines and Occupations",
          "I": "Anthropology, Education, Sociology and Social Phenomena",
          "J": "Technology, Industry, and Agriculture",
          "K": "Humanities",
          "L": "Information Science",
          "M": "Named Groups",
          "N": "Health Care",
          "V": "Publication Characteristics",
          "Z": "Geographicals",
      }
  
      record = get_mesh_record(descriptor)
      if "error" in record:
          return record
  
      return {
          "ui":          record["ui"],
          "label":       record.get("label", ""),
          "treeNumbers": record.get("treeNumbers", []),
          "categories": [
              {"letter": c, "name": _CATEGORY_NAMES.get(c, "Unknown")}
              for c in record.get("treeCategories", [])
          ],
          "broader": record.get("broader", []),
      }