Go "usage: require module/path v1.2.3" malformed go.mod require in CI

By Kaveh Alemi·Latchkey

Every require line in go.mod must name a module path and a version. A line missing the version, or with extra tokens, is rejected with the usage hint for the require directive.

What this error means

A go command fails parsing go.mod with "go.mod:7: usage: require module/path v1.2.3" pointing at a malformed require line.

go.mod:7: usage: require module/path v1.2.3

Common causes

A require line without a version

The module path was added by hand without the v version, so the directive is incomplete.

A merge artifact or stray token on the line

A bad merge left extra text on the require line, breaking the expected two-field form.

How to fix it

Let go mod tidy normalize go.mod

1. Fix the obvious malformed line, then run go mod tidy to canonicalize the file.
2. Commit the corrected go.mod and go.sum.
3. Re-run the build.

go mod tidy

Write the require line by the rule

Each require is module/path version, optionally grouped in a require ( ... ) block.

require (
	example.com/lib v1.4.2
)

How to prevent it

• Edit dependencies with go get/go mod tidy, not by hand.
• Review go.mod diffs after merges for stray tokens.
• Keep require blocks in the canonical two-field form.

Frequently asked questions

Related guides

References

• Go documentation
• GitHub Actions documentation