lighthouse_audit

Run comprehensive Lighthouse audits to measure website performance, accessibility, best practices, and SEO scores. Get detailed findings on render-blocking resources, image optimization, and unused code for actionable improvements.

Instructions

Run a full Lighthouse audit against a URL. Returns scores for Performance, Accessibility, Best Practices, and SEO (0-100), plus detailed audit findings for render-blocking resources, image optimization, unused code, and more. Heavier than performance_audit but provides industry-standard Lighthouse scores.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`url`	Yes	URL of the page to audit (e.g., http://localhost:3000)

Implementation Reference

src/server.ts:558-586 (handler)

The MCP tool registration and handler for 'lighthouse_audit'.

server.tool(
  "lighthouse_audit",
  "Run a full Lighthouse audit against a URL. Returns scores for Performance, Accessibility, Best Practices, and SEO (0-100), plus detailed audit findings for render-blocking resources, image optimization, unused code, and more. Heavier than performance_audit but provides industry-standard Lighthouse scores.",
  {
    url: z.string().url().describe("URL of the page to audit (e.g., http://localhost:3000)"),
  },
  async ({ url }) => {
    try {
      const result = await runLighthouse(url);
      const report = formatLighthouseReport(result);

      return {
        content: [
          { type: "text" as const, text: report },
          {
            type: "text" as const,
            text: `\n\n<raw_data>\n${JSON.stringify(result, null, 2)}\n</raw_data>`,
          },
        ],
      };
    } catch (error) {
      const message = error instanceof Error ? error.message : String(error);
      return {
        content: [{ type: "text" as const, text: `Lighthouse audit failed: ${message}` }],
        isError: true,
      };
    }
  }
);

src/tools/lighthouse.ts:224-227 (handler)

The primary logic implementation for running the Lighthouse audit.

export async function runLighthouse(
  url: string,
  options?: { readonly chromePath?: string }
): Promise<LighthouseResult> {

src/tools/lighthouse.ts:24-31 (schema)

Type definition for the Lighthouse audit results.

export interface LighthouseResult {
  readonly scores: LighthouseScores;
  readonly audits: readonly LighthouseAudit[];
  readonly url: string;
  readonly timestamp: string;
  readonly lighthouseVersion: string;
  readonly runWarnings: readonly string[];
}

mcp-uimax