# `react-doctor/unused-dependency`

A production dependency has no detected project usage

- **Status:** Active
- **Category:** Maintainability
- **Assessment:** Evidence-required risk
- **Required evidence:** source code, repository context
- **Default configuration:** Disabled until configured
- **Default severity:** warn
- **Scope:** All supported frameworks
- **Active when:** full project scans when explicitly configured
- **Tags:** project-analysis
- **Priority:** 32 (P3)
- **Source:** react-doctor-core
- **Rule set:** oxlint-plugin-react-doctor 0.9.3 (prompt schema 2)
- **Documentation:** [Official documentation](https://www.react.doctor/docs/overview/react-maintainability)

## Validation prompt

Confirm the detector match and collect the required evidence before deciding whether an edit is warranted.

This opt-in project rule reports a package from `dependencies` when imports, scripts, config files, plugins, peers, and known framework conventions do not use it. Confirm runtime resolution, generated code, deployment scripts, and external configuration before accepting the finding. Reject dependencies loaded through an unsupported convention.

## Evidence boundary

The diagnostic proves only that the detector's modeled source pattern matched. It does not prove runtime impact, product intent, rendered failure, or that one remediation is correct.

Establish the environment, explicit repository policy, relevant exceptions, and required rendered or runtime evidence before deciding the occurrence. This page’s Assessment and Required evidence fields define the review contract.

Default severity is registry metadata. Use the occurrence's JSON severity after repository configuration when ordering real findings.

Record one outcome:

- **Confirmed failure:** The required evidence establishes the violation.
- **Rejected:** A documented exception or false-positive predicate applies.
- **Needs evidence:** Named evidence can still be collected.
- **Unavailable:** Required evidence cannot be collected in this run.
- **Waived with evidence:** An authorized, scoped exception applies to an established failure.
- **Observation:** The review records an optional tradeoff without claiming a defect.

A waiver records its scope, authority, evidence, and review or expiry condition. It is not a pass or false positive.

## Review a candidate correction

Apply this candidate correction only after the required evidence confirms the risk.

### Reported pattern

```json
{
  "dependencies": {
    "date-fns": "^4.1.0",
    "lodash": "^4.17.21"
  }
}
```

### Candidate corrected pattern

```json
{
  "dependencies": {
    "date-fns": "^4.1.0"
  }
}
```

## Fix prompt

Apply this candidate correction only after the required evidence confirms the risk.

Remove the confirmed unused dependency with the repository's package manager. Update the lockfile, then run a full React Doctor scan, the build, and focused runtime checks.

## Repository-wide copy prompt

Use this only for a repository-wide pass after validating each occurrence. For one occurrence, use the occurrence-level guidance above.

````text
Fix every confirmed `react-doctor/unused-dependency` diagnostic in the current repository.

Required change:
- Remove the confirmed unused dependency with the repository's package manager. Update the lockfile, then run a full React Doctor scan, the build, and focused runtime checks.

Validation before editing:
This opt-in project rule reports a package from `dependencies` when imports, scripts, config files, plugins, peers, and known framework conventions do not use it. Confirm runtime resolution, generated code, deployment scripts, and external configuration before accepting the finding. Reject dependencies loaded through an unsupported convention.

Constraints:
- Confirm every occurrence independently.
- Make the smallest change that addresses the root cause.
- Preserve unrelated behavior, interfaces, content, and semantics.
- Reuse existing project conventions and components.
- Do not suppress the rule merely to clear the report.

Assessment:
- Record detector evidence, applicability, missing evidence, and one outcome: Confirmed failure, Rejected, Needs evidence, Unavailable, Waived with evidence, or Observation.

Verification:
- Run focused tests and every repository-mandated check.
- Run React Doctor and confirm the diagnostic no longer appears from changed code.
- Run an unfiltered scan of the affected scope before claiming no cross-category regression.
- Report checks that were not run instead of claiming they passed.
````