AI coding agent evaluation checklist: from prompt to maintained change

The short answer: compare accepted changes

Choose a representative task in a repository you are authorised to use, define the expected behaviour and give each candidate the same starting state. Compare the accepted implementation, review work and usage consumed. A longer answer, a larger quota or a striking preview does not show whether the team can maintain the result. Start with the AI coding tools category, then keep a written evaluation record.

1. Define a small but meaningful requirement

An example brief might ask for an export filter that excludes archived records while preserving the existing column order. Include ordinary data, an empty result and one edge case that matters to the business. State what the agent may change and what must remain compatible. Use the same clean repository state for each candidate, with sample data and an owner-defined acceptance check. These are proposed exercises, not completed benchmarks.

2. Choose the working surface before the model

A terminal workflow, a full editor and an integrated app-building workspace create different adoption requirements. List the language tooling, extensions, build commands and debugging steps the team uses. Compare Claude Code and Gemini CLI for terminal-oriented work, or Cursor and Devin Desktop for an editor and agent workspace. Verify actual account and version support instead of assuming every surface has identical capabilities.

3. Agree permission and data boundaries

Use an isolated test branch and credentials intended for the pilot. Identify which repository files, shell commands, connected tools and external services the task requires. Have the operator review the permission settings before execution. Record the allowed boundary and how an unwanted action would be rejected. Do not put secrets in the evaluation document or provide production access merely to make a demonstration easier.

4. Keep the plan, diff and review evidence together

Review the plan against the requirement before implementation, then inspect every changed file. Keep the owner-defined checks alongside any generated tests; a test can repeat a mistaken assumption. Record manual repairs, unresolved questions and what the reviewer rejected. The Copilot and Kiro comparison explores repository workflows and specification-led work, while Junie and Kiro separates planning from model and provider costs.

5. Record the account that actually pays

Write down the plan, authentication route, selected model and usage record for the pilot. A free client, a free model and an included subscription allowance are different things. Do not convert one vendor’s credits into another vendor’s messages without a documented rule. Separate trial or promotional capacity from the package the team would retain. Capture any extra usage and the review effort needed before acceptance rather than claiming a universal price per feature.

6. Identify how the app will keep running

A working preview and a retained application have different requirements. Name the hosting target, database, external integrations, billing owner and maintenance process. Confirm whether a preview expires or a required connector needs another package. The Replit Agent and Devin Desktop comparison uses the same app-development brief while distinguishing an integrated platform from the services around a repository-centred workflow.

7. Ask a second maintainer to make a follow-up change

After an implementation is accepted, have another developer inspect the diff and make a related edit. They should be able to find the requirements, understand the code and run the checks without reconstructing the original conversation. Keep project instructions, service ownership and rollback responsibility with the handover. Record what made the task easy or difficult instead of treating the first successful session as proof of long-term maintainability.

Make the decision explainable

Download the four-exercise CSV from each comparison and retain the actual version, account, evidence and reviewer. Use the software comparison scorecard to weight requirements that matter to your team. Leave unknowns unassessed and keep mandatory failures visible. Revisit the decision when the project, retained plan or operating boundary changes. The result should explain why a workflow fits your team; it does not need to declare a universal winner.

Frequently asked questions