When you issue a pull request, you're saying, "I changed some code in this repository -- Please pull my change into the project." You should provide a PR description that tells reviewers what they need to know to evaluate your contribution. Better descriptions give better reviews, which end up with a higher-quality codebase.

Most PRs for a front-end web application should include all of these:

• Purpose: what is this change trying to accomplish? Linking to specifications or tickets is fine, but you must include a one-sentence explanation in the PR description itself.
• Approach: how does this change accomplish its goal? Explain your approach's architecture at a high level.
• Worries: Is there anything weird here? Do you have any areas you want help?
• Before & after screenshots, if the change is visual
• How to use the feature or exercise the change. Just linking to a ticket with a bug description is not enough; tell the reviewer how they can verify for themselves that the feature is working as planned.

Larger PRs should also include:

• Did you consider alternative approaches? Why did you go with the approach you chose?
• How does this relate to other work? Link to other PRs or describe future plans.