collection-indexes

Describe indexes for a MongoDB collection to understand query performance and optimize database operations by analyzing index structure and usage.

Instructions

Describe the indexes for a collection

Input Schema

TableJSON Schema

Name	Required	Description	Default
`database`	Yes	Database name
`collection`	Yes	Collection name

Implementation Reference

src/tools/mongodb/metadata/collectionIndexes.ts:25-52 (handler)

The main handler function that connects to MongoDB, fetches regular indexes and optional search indexes, formats them as JSON strings in the tool response.

protected async execute({ database, collection }: ToolArgs<typeof DbOperationArgs>): Promise<CallToolResult> {
    const provider = await this.ensureConnected();
    const indexes = await provider.getIndexes(database, collection);
    const indexDefinitions: IndexStatus[] = indexes.map((index) => ({
        name: index.name as string,
        key: index.key as Document,
    }));

    const searchIndexDefinitions: SearchIndexStatus[] = [];
    if (this.isFeatureEnabled("search") && (await this.session.isSearchSupported())) {
        const searchIndexes = await provider.getSearchIndexes(database, collection);
        searchIndexDefinitions.push(...this.extractSearchIndexDetails(searchIndexes));
    }

    return {
        content: [
            ...formatUntrustedData(
                `Found ${indexDefinitions.length} indexes in the collection "${collection}":`,
                ...indexDefinitions.map((i) => JSON.stringify(i))
            ),
            ...(searchIndexDefinitions.length > 0
                ? formatUntrustedData(
                      `Found ${searchIndexDefinitions.length} search and vector search indexes in the collection "${collection}":`,
                      ...searchIndexDefinitions.map((i) => JSON.stringify(i))
                  )
                : []),
        ],
    };

src/tools/mongodb/mongodbTool.ts:11-14 (schema)
Zod schema defining the input arguments 'database' and 'collection' used by the collection-indexes tool and other MongoDB tools.
```
export const DbOperationArgs = {
    database: z.string().describe("Database name"),
    collection: z.string().describe("Collection name"),
};
```

src/tools/mongodb/metadata/collectionIndexes.ts:19-23 (registration)

Tool class definition including the unique name 'collection-indexes', description, input schema reference, and operation type.

export class CollectionIndexesTool extends MongoDBToolBase {
    public name = "collection-indexes";
    protected description = "Describe the indexes for a collection";
    protected argsShape = DbOperationArgs;
    static operationType: OperationType = "metadata";

src/tools/mongodb/tools.ts:3-3 (registration)
Re-export of the CollectionIndexesTool class from the MongoDB tools barrel file for easy import and registration.
```
export { CollectionIndexesTool } from "./metadata/collectionIndexes.js";
```

src/tools/mongodb/metadata/collectionIndexes.ts:80-88 (helper)

Helper method to extract relevant details from search index definitions, simplifying status, queryability, and definition for the response.

protected extractSearchIndexDetails(indexes: Record<string, unknown>[]): SearchIndexStatus[] {
    return indexes.map((index) => ({
        name: (index["name"] ?? "default") as string,
        type: (index["type"] ?? "UNKNOWN") as string,
        status: (index["status"] ?? "UNKNOWN") as string,
        queryable: (index["queryable"] ?? false) as boolean,
        latestDefinition: index["latestDefinition"] as Document,
    }));
}

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