docs.rs MCP

Instructions

Implementation Reference

• src/index.ts:325-396 (handler)

  The `searchInCrate` function is the main handler that executes the tool's logic. It scrapes the crate's all.html page on docs.rs, identifies item links by type, filters by query and optional item_type, deduplicates, and returns formatted markdown results with documentation links.

  private async searchInCrate(args: any) {
      const { crate_name, query, version = "latest", item_type } = args;
  
      try {
          const url = `https://docs.rs/${crate_name}/${version}/${crate_name}/all.html`;
          const response = await axios.get<string>(url);
          const $ = cheerio.load(response.data);
  
          const items: Array<{
              name: string;
              type: string;
              link: string;
          }> = [];
  
          $("#main-content a").each((_, element) => {
              const $link = $(element);
              const itemName = $link.text().trim();
              const itemLink = $link.attr("href") || "";
  
              if (!itemName || !itemLink) return;
  
              let type = "unknown";
              if (itemLink.includes("struct.")) type = "struct";
              else if (itemLink.includes("trait.")) type = "trait";
              else if (itemLink.includes("fn.")) type = "function";
              else if (itemLink.includes("enum.")) type = "enum";
              else if (itemLink.includes("type.")) type = "type";
              else if (itemLink.includes("const.")) type = "constant";
              else if (itemLink.includes("static.")) type = "static";
              else if (itemLink.includes("macro.")) type = "macro";
  
              const matchesQuery = !query || query == "" || itemName.toLowerCase().includes(query.toLowerCase());
              const matchesType = !item_type || item_type == "" || type === item_type || itemName.toLowerCase().includes(item_type.toLowerCase());
  
              if (matchesQuery && matchesType && type !== "unknown") {
                  items.push({
                      name: itemName,
                      type,
                      link: itemLink.startsWith("http") ? itemLink : `https://docs.rs/${crate_name}/${version}/${crate_name}/${itemLink}`,
                  });
              }
          });
  
          const uniqueItems = items.filter((item, index, self) =>
              index === self.findIndex(i => i.name === item.name && i.type === item.type)
          );
  
          const searchTerm = query || "all items";
          return {
              content: [
                  {
                      type: "text",
                      text: `# Search Results for "${searchTerm}" in ${crate_name}\n\n` +
                          `Found ${uniqueItems.length} items\n\n` +
                          (uniqueItems.length === 0
                              ? "No matching items found."
                              : uniqueItems
                                  .map(
                                      (item) =>
                                          `## ${item.name} (${item.type})\n\n` +
                                          `**Description:** ${item.type}\n\n` +
                                          `**Link:** [View Documentation](${item.link})\n\n` +
                                          `---\n`
                                  )
                                  .join("\n")
                          ),
                  },
              ],
          };
      } catch (error) {
          throw new Error(`Failed to search items in ${crate_name}: ${error}`);
      }

• src/index.ts:119-139 (schema)

  Input schema defining the parameters for the `docs_rs_search_in_crate` tool: crate_name (required), query (required), version (optional), item_type (optional).

  inputSchema: {
      type: "object",
      properties: {
          crate_name: {
              type: "string",
              description: "Name of the crate to search",
          },
          query: {
              type: "string",
              description: "Search keyword (trait name, struct name, function name, etc.)",
          },
          version: {
              type: "string",
              description: "Specific version (optional, defaults to latest)",
          },
          item_type: {
              type: "string",
              description: "Filter by item type (struct | trait | fn | enum| union | macro | constant)",
          },
      },
      required: ["crate_name", "query"],

• src/index.ts:116-141 (registration)

  Tool registration in the ListToolsRequestHandler response, including name, description, and input schema.

  {
      name: "docs_rs_search_in_crate",
      description: "Search for traits, structs, methods, etc. from the crate's all.html page. To get a module, use docs_rs_get_item instead.",
      inputSchema: {
          type: "object",
          properties: {
              crate_name: {
                  type: "string",
                  description: "Name of the crate to search",
              },
              query: {
                  type: "string",
                  description: "Search keyword (trait name, struct name, function name, etc.)",
              },
              version: {
                  type: "string",
                  description: "Specific version (optional, defaults to latest)",
              },
              item_type: {
                  type: "string",
                  description: "Filter by item type (struct | trait | fn | enum| union | macro | constant)",
              },
          },
          required: ["crate_name", "query"],
      },
  },

• src/index.ts:155-156 (registration)

  Dispatch case in the CallToolRequestHandler switch statement that routes calls to the searchInCrate handler.

  case "docs_rs_search_in_crate":
      return await this.searchInCrate(request.params.arguments);