# go: missing go.sum entry for module providing package X; to add: go mod download X

- **ID:** `go/missing-go-sum`
- **Domain:** go
- **Category:** module_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

The go.sum file is missing a checksum entry for a required module, often due to manual go.mod edits.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 1.16 | active | — | — |
| 1.17 | active | — | — |

## Workarounds

1. **运行go mod tidy更新go.sum** (90% success)
   ```
   go mod tidy
   ```
2. **运行go mod download指定模块** (80% success)
   ```
   go mod download github.com/example/pkg
   ```

## Dead Ends

- **手动编辑go.sum添加条目** — go.sum是自动生成的，手动编辑容易出错且不完整。 (90% fail)
- **忽略错误继续构建** — Go工具会阻止构建，必须修复。 (100% fail)