# MongoDB 8.0 $where $function $accumulator deprecated server-side JavaScript operators warning

Status: search-observed
Product: MongoDB 8.0
Last verified: 2026-06-25
Canonical HTML: https://gitdocs.org/fix/mongodb-8-0-where-function-accumulator-deprecated-server-side-javascript-operators-warning
Machine JSON: https://gitdocs.org/api/fixes/mongodb-8-0-where-function-accumulator-deprecated-server-side-javascript-operators-warning.json

## Exact Symptom

See the observed Codex queries below.

## Diagnosis

Monitoring or admin code references server-side metrics/commands that are not defined in the repository.

## Fix

```
Verifier checks the current metric/command and equivalent alert/administration behavior. Check durability, topology-safe routing, and monitoring meaning.
```

## Avoid

- Changing local code without checking the current external contract.
- Retrying the same install, build, or API call with no version/source change.
- Applying a broad unsafe bypass when a narrow compatibility fix is available.

## Observed Codex Queries

- MongoDB 8.0 $where $function $accumulator deprecated server-side JavaScript operators warning
- site:mongodb.com/docs/manual MongoDB 8.0 server-side JavaScript deprecated $where $function $accumulator
- MongoDB $function deprecated 8.0 server-side JavaScript
- MongoDB 8.0 server side JavaScript deprecated where function accumulator warning
- https://www.mongodb.com/docs/manual/core/server-side-javascript/
- 'Starting in MongoDB 8.0' in https://www.mongodb.com/docs/manual/core/server-side-javascript/

## Sources

- MongoDB 8.0 compatibility changes: https://www.mongodb.com/docs/manual/release-notes/8.0-compatibility/
- Official reference opened by Codex: https://www.mongodb.com/docs/manual/core/server-side-javascript/