chore: check that a vector search index exists with indexCheck

[kmruiz]

Proposed changes

Checklist

• I have signed the MongoDB CLA

[Copilot]

Pull Request Overview

This PR adds validation to check that a vector search index exists before executing aggregate queries that use $vectorSearch, preventing errors from being thrown during query execution. This validation is controlled by the indexCheck configuration option.

Key Changes:

• Added indexExists method to VectorSearchEmbeddingsManager to verify index existence
• Modified AggregateTool to validate vector search indexes before executing aggregation pipelines
• Added integration test to verify error handling when a non-existent vector search index is referenced

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
src/common/search/vectorSearchEmbeddingsManager.ts	Added indexExists method to check if a vector search index exists in the database
src/tools/mongodb/read/aggregate.ts	Added isVectorSearchIndexUsed method and index validation logic that throws an error when a non-existent vector search index is referenced
tests/integration/tools/mongodb/read/aggregate.test.ts	Added test case to verify error handling for non-existent vector search indexes and enabled indexCheck in test configuration

[coveralls]

Pull Request Test Coverage Report for Build 18871399446

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 51 of 55 (92.73%) changed or added relevant lines in 2 files are covered.
• 28 unchanged lines in 2 files lost coverage.
• Overall coverage increased (+0.1%) to 80.225%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/common/search/vectorSearchEmbeddingsManager.ts	11	13	84.62%
src/tools/mongodb/read/aggregate.ts	40	42	95.24%

Files with Coverage Reduction	New Missed Lines	%
src/common/config.ts	14	89.7%
src/tools/tool.ts	14	78.64%

Totals
Change from base Build 18840683408:	0.1%
Covered Lines:	6355
Relevant Lines:	7781

---

💛 - Coveralls

[himanshusinghs]

Suggested change

	const indexExists = await this.session.vectorSearchEmbeddingsManager.indexExists({
	database,
	collection,
	indexName,
	});
	return indexExists;
	return await this.session.vectorSearchEmbeddingsManager.indexExists({
	database,
	collection,
	indexName,
	});

[nirinchev]

I would expect we'd get an error from the server if we try to use $vectorSearch

[kmruiz]

I would expect we'd get an error from the server if we try to use $vectorSearch

https://www.mongodb.com/docs/atlas/atlas-vector-search/vector-search-stage/#fields

MongoDB Vector Search doesn't return results if you misspell the index name or if the specified index doesn't already exist on the cluster.

🥲