# X_EXERCISE_REQUEST_INVALID

## Means

an exercise entry's request is not one a browser could send

## Typical cause

a request: in apps/web/exercise.ts names a cookie outside the token set, puts a Cookie header beside cookies, or a header Headers refuses

## Fix

`defineExercise({ <name>: { request: { cookies: { <token>: '<value>' }, headers: { '<x-name>': '<value>' } } } })` — in apps/web/exercise.ts

[HTTP](/error-codes#http)