feat: add data access tools (#14)

Author: nirinchev

package-lock.json

@@ -14,6 +14,7 @@
   "publishConfig": {
     "access": "public"
   },
+  "type": "module",
   "scripts": {
     "prepare": "npm run build",
     "build:clean": "rm -rf dist",
@@ -40,11 +41,16 @@
     "globals": "^16.0.0",
     "prettier": "^3.5.3",
     "typescript": "^5.8.2",
-    "typescript-eslint": "^8.29.1",
-    "zod": "^3.24.2"
+    "typescript-eslint": "^8.29.1"
   },
   "dependencies": {
-    "@types/express": "^5.0.1"
+    "@mongodb-js/devtools-connect": "^3.7.2",
+    "@mongosh/service-provider-node-driver": "^3.6.0",
+    "@types/express": "^5.0.1",
+    "bson": "^6.10.3",
+    "mongodb": "^6.15.0",
+    "mongodb-schema": "^12.6.2",
+    "zod": "^3.24.2"
   },
   "engines": {
     "node": ">=23.0.0"

package.json

@@ -1,7 +1,11 @@
 import path from "path";
 import fs from "fs";
+import { fileURLToPath } from "url";
 
-const packageMetadata = fs.readFileSync(path.resolve("./package.json"), "utf8");
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+
+const packageMetadata = fs.readFileSync(path.join(__dirname, "..", "package.json"), "utf8");
 const packageJson = JSON.parse(packageMetadata);
 
 export const config = {

src/config.ts

@@ -0,0 +1,4 @@
+export enum ErrorCodes {
+    NotConnectedToMongoDB = 1_000_000,
+    InvalidParams = 1_000_001,
+}

src/errors.ts

@@ -1,9 +1,8 @@
-import { ZodRawShape } from "zod";
 import { ToolBase } from "../tool.js";
 import { ApiClient } from "../../client.js";
 import { State } from "../../state.js";
 
-export abstract class AtlasToolBase<Args extends ZodRawShape = ZodRawShape> extends ToolBase<Args> {
+export abstract class AtlasToolBase extends ToolBase {
     constructor(
         state: State,
         protected apiClient: ApiClient

src/tools/atlas/atlasTool.ts

@@ -5,10 +5,9 @@ import { ensureAuthenticated } from "./auth.js";
 import { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
 import { AtlasToolBase } from "./atlasTool.js";
 import { State } from "../../state.js";
+import { ToolArgs } from "../tool.js";
 
-export class ListClustersTool extends AtlasToolBase<{
-    projectId: ZodString | ZodOptional<ZodString>;
-}> {
+export class ListClustersTool extends AtlasToolBase {
     protected name = "listClusters";
     protected description = "List MongoDB Atlas clusters";
     protected argsShape;
@@ -29,7 +28,7 @@ export class ListClustersTool extends AtlasToolBase<{
         };
     }
 
-    protected async execute({ projectId }: { projectId: string }): Promise<CallToolResult> {
+    protected async execute({ projectId }: ToolArgs<typeof this.argsShape>): Promise<CallToolResult> {
         await ensureAuthenticated(this.state, this.apiClient);
 
         let clusters: AtlasCluster[] | undefined = undefined;

src/tools/atlas/listClusters.ts

@@ -1,4 +1,3 @@
-import { ZodRawShape } from "zod";
 import { ToolBase } from "../tool.js";
 import { ApiClient } from "../../client.js";
 import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
@@ -8,7 +7,7 @@ import { ListClustersTool } from "./listClusters.js";
 import { ListProjectsTool } from "./listProjects.js";
 
 export function registerAtlasTools(server: McpServer, state: State, apiClient: ApiClient) {
-    const tools: ToolBase<ZodRawShape>[] = [
+    const tools: ToolBase[] = [
         new AuthTool(state, apiClient),
         new ListClustersTool(state, apiClient),
         new ListProjectsTool(state, apiClient),

src/tools/atlas/tools.ts

@@ -0,0 +1,24 @@
+import { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
+import { DbOperationArgs, DbOperationType, MongoDBToolBase } from "./mongodbTool.js";
+import { ToolArgs } from "../tool.js";
+
+export class CollectionIndexesTool extends MongoDBToolBase {
+    protected name = "collection-indexes";
+    protected description = "Describe the indexes for a collection";
+    protected argsShape = DbOperationArgs;
+    protected operationType: DbOperationType = "read";
+
+    protected async execute({ database, collection }: ToolArgs<typeof DbOperationArgs>): Promise<CallToolResult> {
+        const provider = this.ensureConnected();
+        const indexes = await provider.getIndexes(database, collection);
+
+        return {
+            content: indexes.map((indexDefinition) => {
+                return {
+                    text: `Field: ${indexDefinition.name}: ${JSON.stringify(indexDefinition.key)}`,
+                    type: "text",
+                };
+            }),
+        };
+    }
+}

src/tools/mongodb/collectionIndexes.ts

@@ -0,0 +1,75 @@
+import { z } from "zod";
+import { CallToolResult, McpError } from "@modelcontextprotocol/sdk/types.js";
+import { NodeDriverServiceProvider } from "@mongosh/service-provider-node-driver";
+import { DbOperationType, MongoDBToolBase } from "./mongodbTool.js";
+import { ToolArgs } from "../tool";
+import { ErrorCodes } from "../../errors.js";
+
+export class ConnectTool extends MongoDBToolBase {
+    protected name = "connect";
+    protected description = "Connect to a MongoDB instance";
+    protected argsShape = {
+        connectionStringOrClusterName: z
+            .string()
+            .optional()
+            .describe("MongoDB connection string (in the mongodb:// or mongodb+srv:// format) or cluster name"),
+    };
+
+    protected operationType: DbOperationType = "metadata";
+
+    protected async execute({
+        connectionStringOrClusterName,
+    }: ToolArgs<typeof this.argsShape>): Promise<CallToolResult> {
+        if (!connectionStringOrClusterName) {
+            // TODO: try reconnecting to the default connection
+            return {
+                content: [
+                    { type: "text", text: "No connection details provided." },
+                    { type: "text", text: "Please provide either a connection string or a cluster name" },
+                    {
+                        type: "text",
+                        text: "Alternatively, you can use the default deployment at mongodb://localhost:27017",
+                    },
+                ],
+            };
+        }
+
+        let connectionString: string;
+
+        if (typeof connectionStringOrClusterName === "string") {
+            if (
+                connectionStringOrClusterName.startsWith("mongodb://") ||
+                connectionStringOrClusterName.startsWith("mongodb+srv://")
+            ) {
+                connectionString = connectionStringOrClusterName;
+            } else {
+                // TODO:
+                return {
+                    content: [
+                        {
+                            type: "text",
+                            text: `Connecting via cluster name not supported yet. Please provide a connection string.`,
+                        },
+                    ],
+                };
+            }
+        } else {
+            throw new McpError(ErrorCodes.InvalidParams, "Invalid connection options");
+        }
+
+        await this.connect(connectionString);
+
+        return {
+            content: [{ type: "text", text: `Successfully connected to ${connectionString}.` }],
+        };
+    }
+
+    private async connect(connectionString: string): Promise<void> {
+        const provider = await NodeDriverServiceProvider.connect(connectionString, {
+            productDocsLink: "https://docs.mongodb.com/todo-mcp",
+            productName: "MongoDB MCP",
+        });
+
+        this.mongodbState.serviceProvider = provider;
+    }
+}

src/tools/mongodb/connect.ts

@@ -0,0 +1,40 @@
+import { z } from "zod";
+import { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
+import { DbOperationArgs, DbOperationType, MongoDBToolBase } from "../mongodbTool.js";
+import { ToolArgs } from "../../tool.js";
+
+export class InsertManyTool extends MongoDBToolBase {
+    protected name = "insert-many";
+    protected description = "Insert an array of documents into a MongoDB collection";
+    protected argsShape = {
+        ...DbOperationArgs,
+        documents: z
+            .array(z.object({}).passthrough().describe("An individual MongoDB document"))
+            .describe(
+                "The array of documents to insert, matching the syntax of the document argument of db.collection.insertMany()"
+            ),
+    };
+    protected operationType: DbOperationType = "create";
+
+    protected async execute({
+        database,
+        collection,
+        documents,
+    }: ToolArgs<typeof this.argsShape>): Promise<CallToolResult> {
+        const provider = this.ensureConnected();
+        const result = await provider.insertMany(database, collection, documents);
+
+        return {
+            content: [
+                {
+                    text: `Inserted \`${result.insertedCount}\` documents into collection \`${collection}\``,
+                    type: "text",
+                },
+                {
+                    text: `Inserted IDs: ${Object.values(result.insertedIds).join(", ")}`,
+                    type: "text",
+                },
+            ],
+        };
+    }
+}