get_full_text_links

Retrieve free full-text article links from PubMed Central and publisher sources using a PubMed ID to access biomedical research.

Instructions

Get links to free full text versions of an article (e.g., PubMed Central). Returns PMC links and publisher free-access URLs.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`pmid`	Yes	PubMed ID to find full text links for

Implementation Reference

src/tools.ts:173-221 (handler)

The getFullTextLinks handler function that retrieves full text links for a PubMed article by calling NCBI's elink API. It fetches both PMC (PubMed Central) links and provider links, returning a JSON response with the PMID, full_text_links array, and a boolean indicating if free full text is available.

export async function getFullTextLinks(args: z.infer<typeof getFullTextLinksSchema>): Promise<string> {
  // Use elink to find PMC links and provider links
  const result = await client.elinkCmd([args.pmid], "llinks", "pubmed") as {
    linksets?: Array<{
      idurllist?: Array<{
        objurls?: Array<{
          url?: { value?: string };
          linkname?: string;
          provider?: { name?: string[] };
          categories?: Array<{ category?: string }>;
        }>;
      }>;
    }>;
  };

  // Also check for PMC link
  const pmcResult = await client.elink([args.pmid], "pubmed_pmc", "pubmed", "pmc") as {
    linksets?: Array<{ linksetdbs?: Array<{ links?: string[] }> }>;
  };

  const pmcIds = pmcResult.linksets?.[0]?.linksetdbs?.[0]?.links || [];
  const links: Array<Record<string, string>> = [];

  if (pmcIds.length > 0) {
    links.push({
      source: "PubMed Central",
      url: `https://www.ncbi.nlm.nih.gov/pmc/articles/PMC${pmcIds[0]}/`,
      pmcid: `PMC${pmcIds[0]}`,
    });
  }

  // Extract provider links
  const urlList = result.linksets?.[0]?.idurllist?.[0]?.objurls || [];
  for (const obj of urlList) {
    const url = obj.url?.value;
    if (url) {
      links.push({
        source: obj.provider?.name?.[0] || obj.linkname || "Unknown",
        url,
      });
    }
  }

  return JSON.stringify({
    pmid: args.pmid,
    full_text_links: links,
    has_free_full_text: links.length > 0,
  }, null, 2);
}

src/tools.ts:35-37 (schema)
The Zod schema definition for getFullTextLinks that validates the input parameters. It requires a single parameter: pmid (PubMed ID as a string).
```
export const getFullTextLinksSchema = z.object({
  pmid: z.string().describe("PubMed ID to find full text links for"),
});
```

src/index.ts:70-77 (registration)

Tool registration that registers get_full_text_links with the MCP server. It includes the tool name, description, schema shape, and the handler that calls getFullTextLinks with parsed arguments.

server.tool(
  "get_full_text_links",
  "Get links to free full text versions of an article (e.g., PubMed Central). Returns PMC links and publisher free-access URLs.",
  getFullTextLinksSchema.shape,
  async (args) => ({
    content: [{ type: "text", text: await getFullTextLinks(getFullTextLinksSchema.parse(args)) }],
  })
);

mcp-pubmed