WordPress 
A useful software specification describes behavior that another person can verify. It gives an AI coding assistant the same foundation a developer needs: the problem, relevant context, boundaries, and a definition of a successful result. Length matters less than clarity.
Consider a request to build a CSV import screen. That request leaves almost everything open. Which columns are required? Can users preview changes? What happens when two rows use the same identifier? Who can import data? An assistant may answer those questions implicitly in code, even though no one agreed to the answers.
Describe the user journey first
Write the steps in ordinary language. An authorized administrator selects a CSV file, receives validation feedback, previews accepted rows, confirms the import, and sees a result summary. A failed validation makes no persistent changes. A cancelled preview leaves the existing records untouched.
Include a small invented example file and the expected output. Concrete examples reveal ambiguities that a paragraph can hide. State how blank fields, duplicate identifiers, unexpected columns, character encoding, and oversized files should behave.
Define constraints before implementation
List the existing framework, supported runtime versions, database conventions, and components the application should reuse. Identify files or integrations that must stay intact. If the import belongs in an established application, point to a similar screen and its permission checks.
Separate requirements from preferences. A requirement might prohibit importing another organization’s data. A preference might ask for a particular layout. That distinction helps a developer choose a safe implementation when a visual detail conflicts with the existing design system.
Make acceptance criteria observable
Good acceptance criteria describe evidence. For example: an unauthorized user receives a denied response and no records are created; a file missing the email column displays an actionable message; importing the same confirmed batch twice follows the documented duplicate rule.
Avoid criteria such as works well, secure, or production ready without a defined check. Break them into specific responsibilities. Decide what must be tested automatically, what needs a manual walkthrough, and which security assumptions need someone qualified to review them.
Include failure and recovery paths
Think about an import that stops after some rows are processed. Should the application roll back the entire batch, retain completed rows with a resumable job, or stop before making changes? The answer depends on the product, but it should be explicit.
Specify what users can safely retry, what information goes into logs, and what must never appear there. Define how the system communicates progress without exposing private information. These details are part of the feature, even if the first demonstration never encounters a failure.
Use the specification as a review tool
- Ask the assistant to identify missing decisions before editing code.
- Request a small implementation plan tied to the acceptance criteria.
- Review one meaningful change at a time.
- Compare the delivered behavior with examples and failure cases.
- Update the specification when an agreed decision changes.
The specification should remain readable after the initial build. It can guide documentation, support, and future changes. If you are still deciding which features belong in the first version, use the MVP scope guide to reduce the work to one complete customer outcome.