Piloting an AI coding agent on an existing project
Choose a bounded module, prepare development notes and reproduction steps, then review code changes and test results when introducing an AI coding agent to an existing project.
Start an AI coding-agent pilot on an existing project with a small module and a specific change request. A reproducible defect or bounded feature is easier to evaluate than a request to understand and improve an entire repository.
The first task should establish a repeatable path from reading files to editing, running, and reviewing them. The number of changed lines is not a useful measure of whether that process works.
Choose a task with a visible boundary
Look for work that meets three conditions:
- You can identify the relevant files and feature boundary.
- You can reproduce the problem or describe expected behavior.
- A person can check the result.
Examples include date-validation errors, CSV column handling, a small responsive-layout issue, or refactoring a repeated function. A first pilot involving a complete authentication redesign or several services is harder to control.
Check formats and project size
The current Wissly Code beta reads UTF-8 text and skips EUC-KR files and files larger than 200KB. Each project supports up to 1,000 files totaling 5MB. These are constraints on existing-project input, so prepare the required module instead of bringing the entire repository indiscriminately.
Focus on source, configuration, development notes, and tests. Exclude dependency folders, build outputs, and large generated files from the working set. Check that excluded material does not remove information required for the build or tests. A separate working copy makes review and reversal easier without changing the original repository.
Include concise development notes
| Item | What to describe |
|---|---|
| Module purpose | Inputs, outputs, and responsibility |
| Execution | Language, version, and run command |
| Tests | Commands and test data |
| Change request | The problem and expected behavior |
| Boundaries | Allowed files and interfaces to preserve |
| Constraints | Inaccessible systems or unavailable packages |
For example, specify that a CSV row with an empty date should go to an error list while valid rows continue processing. “Improve stability” does not provide a checkable outcome.
Establish current behavior before edits
Run the existing tests and confirm the execution method. If a test already fails, record whether that failure relates to the intended change. For a defect, retain the input, error message, and reproduction steps.
For a Node.js project, npm ci's installation requirements are relevant to the lockfile and environment. On an isolated network, the required packages also need to be available even when the command is correct.
Separate understanding, editing, and review
First ask the agent to explain the relevant files and flow. Confirm change scope and completion conditions, then request the edit. A person reviews both the changed files and execution results.
An example request is:
In the CSV processing module, put rows with an empty date into an error list. Preserve existing output column names. Check a missing-date case and a valid case, and show the changed files and execution results.
Wissly Code provides file changes and an application preview. A working preview and correct business rules are separate checks. Run normal and error inputs for the changed feature, then check relevant existing behavior.
Bring reviewed changes back into the project
Inspect differences for unrelated configuration changes, unnecessary dependencies, hardcoded values, and secrets. Record the change purpose and tests in the team's review process.
Wissly Code can prepare CI/CD settings, Dockerfiles, deployment and rollback scripts, and help run project builds and tests. Actual image builds, production deployment, and rollback take place after review through internal CI/CD.
Reuse the execution instructions and review criteria on the next task. The isolated-network setup guide covers preparation, and Wissly Code explains the workflow and beta access.
The product screenshot shows the Korean interface.