Reviewers have little control over whether articles they review are openly and immediately accessible to the community via a preprint server, and whether the data and code presented are made openly available to the community. Using this form, invited reviewers can anonymously enter into an agreement with the authors before they accept an invitation to review a manuscript. Authors who do make their work openly accessible will then be able to access faster review times, and also benefit from having open reviews, which are more transferable between journals. See our blog for more information. You can set your own open peer review preferences here (requires login via ORCiD or Twitter).
The reviewer specifies what they would like the author to agree to in terms of openness, and the reviewer also specifies what they are willing to commit to in terms of making their review content open. The authors are then able to accept, decline or suggest modifications to the agreement. Once the author and invited reviewer are agreed, the reviewer accepts the assignment from the journal. A record of the review agreement is kept for future reference.