Clojars-MCP-Server

Instructions

Implementation Reference

• src/index.ts:132-189 (handler)

  The handler for the 'get_clojars_latest_version' tool. Validates input, fetches Maven metadata XML from Clojars, parses latest version using regex, returns JSON with version or error message.

  if (request.params.name === 'get_clojars_latest_version') {
    if (!isValidDependencyArgs(request.params.arguments)) {
      throw new McpError(
        ErrorCode.InvalidParams,
        'Invalid dependency format. Expected "group/artifact" (e.g. "metosin/reitit")'
      );
    }
  
    const [group, artifact] = request.params.arguments.dependency.split('/');
  
    try {
      const response = await this.axiosInstance.get<string>(
        `/${group.replace(/\./g, '/')}/${artifact}/maven-metadata.xml`
      );
  
      // Extract latest version from XML
      const versionMatch = response.data.match(/<latest>(.*?)<\/latest>/);
      const releaseMatch = response.data.match(/<release>(.*?)<\/release>/);
      const latestVersion = releaseMatch?.[1] || versionMatch?.[1];
  
      if (!latestVersion) {
        throw new Error('Could not find version information in metadata');
      }
  
      return {
        content: [
          {
            type: 'text',
            text: JSON.stringify(
              {
                dependency: `${group}/${artifact}`,
                latest_version: latestVersion
              },
              null,
              2
            ),
          },
        ],
      };
    } catch (error) {
      if (axios.isAxiosError(error)) {
        const message = error.response?.status === 404
          ? `Dependency ${group}/${artifact} not found on Clojars`
          : `Clojars API error: ${error.message}`;
        
        return {
          content: [
            {
              type: 'text',
              text: message,
            },
          ],
          isError: true,
        };
      }
      throw error;
    }
  } else if (request.params.name === 'check_clojars_version_exists') {

• src/index.ts:76-89 (registration)

  Registration of the tool in the ListTools response, including name, description, and input schema.

  {
    name: 'get_clojars_latest_version',
    description: 'Get the latest version of a Clojars dependency (Maven artifact)',
    inputSchema: {
      type: 'object',
      properties: {
        dependency: {
          type: 'string',
          description: 'Clojars dependency name in format "group/artifact" (e.g. "metosin/reitit")',
        },
      },
      required: ['dependency'],
    },
  },

• src/index.ts:79-88 (schema)

  Input schema for validating the tool's arguments: requires 'dependency' as string in 'group/artifact' format.

  inputSchema: {
    type: 'object',
    properties: {
      dependency: {
        type: 'string',
        description: 'Clojars dependency name in format "group/artifact" (e.g. "metosin/reitit")',
      },
    },
    required: ['dependency'],
  },

• src/index.ts:19-23 (helper)

  Helper function to validate the dependency argument format before processing.

  const isValidDependencyArgs = (args: any): args is { dependency: string } =>
    typeof args === 'object' &&
    args !== null &&
    typeof args.dependency === 'string' &&
    args.dependency.includes('/');