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Use Claude to explain code, identify possible risks, and propose tests while keeping validation in your engineering process. Review the diff, execute relevant checks, inspect dependencies, and approve the result. Claude Code can interact with project files and tools, so establish its working directory and permissions before starting.
The useful starting point is a small, reviewable task. A confident explanation is a suggestion to investigate, not evidence that the application meets its requirements or that a command was executed.
Define a task with an observable result
Ask for a specific function explanation, a missing regression case, or a review of a bounded diff. “Improve everything” does not establish scope or acceptance criteria. State the expected behavior, authorized files, permitted commands, and conditions requiring a stop.
For a bug, provide reproduction steps and expected output without real customer data or credentials. Ask for the hypothesis, code location, supporting evidence, proposed test, and remaining uncertainty separately.
This makes disagreement useful. If the proposed cause does not fit the caller or input contract, the reviewer can reject that hypothesis without losing track of the original requirement.
Check the installation and account arrangement
Use the current Claude Code setup documentation for the chosen operating system and installation method. Native installation and npm installation have different prerequisites; do not apply one method’s requirements to every setup.
Likewise, confirm the authentication and billing route available to the account. An eligible Claude subscription and API or Console billing are different arrangements. Do not assume that a familiar subscription name settles every development-tool entitlement or usage charge.
Record the tool version and account context when they matter to reproducing a change. Avoid turning a setup note into a permanent claim about every future release.
Preserve existing work before allowing edits
Inspect git status, preserve current work appropriately, and use a branch or controlled checkout. A clean starting point makes the agent’s changes easier to distinguish from work that already existed.
Open only the repository required for the task and review additional directories. A customer project should use a controlled development environment rather than casually exposing the production filesystem.
Understand commands before running them, especially installers, migrations, network operations, and removal commands. A proposed command is an action on the machine, not merely another paragraph in a code explanation.
Do not treat Git exclusions as a security boundary
The Git ignore documentation concerns which files Git ignores for tracking purposes. It does not make a file unreadable to an application operating in the directory.
Anthropic’s permission documentation describes file-tool rules, including Read deny rules. Review the rules together with shell access and subprocess behavior; one file-tool restriction should not be presented as complete operating-system isolation.
Keep unnecessary secrets outside the accessible environment. Do not rely solely on an instruction asking the model not to inspect them. Separate the repository, execution identity, and credential access according to the project’s needs.
Grant tools according to the actual task
Reading a function, editing an authorized file, and running an established test command are distinct permissions. Review the CLI reference and permission controls instead of granting unrestricted operation for convenience.
For an initial assessment, keep risky operations reviewable. Unexpected requests involving production, databases, infrastructure, credentials, or unrelated directories are a reason to reassess the scope.
A mode that bypasses permission prompts is not an appropriate default for a first project review. The goal is an environment whose allowed actions fit the work, not repeated approval of commands nobody understands.
Protect secrets and customer information
Do not paste environment files, private keys, production tokens, cookies, or identifiable database dumps into the prompt. Prepare synthetic examples and remove unnecessary confidential material from the working copy.
If a secret is exposed, follow the organization’s response process, including revocation and replacement where required. Deleting a sentence from the prompt is not proof that an active credential has been invalidated.
Review logs and artifacts produced during the task. A permitted tool call still needs to follow the organization’s data policy and the provider’s applicable terms. Authorization to edit code does not authorize distributing customer records.
Turn a suggestion into a reproducible review
Ask for the file, relevant passage, assumptions, and a test that would distinguish the proposed explanation from alternatives. Inspect the surrounding code and callers. A warning without a concrete location remains a hypothesis.
Run the project’s relevant checks in the appropriate environment. Begin with focused tests or linting, then use integration checks when the change requires them. Preserve a failure’s original output before accepting another proposed repair.
Review the test itself. An agent can write a test that repeats its mistaken assumption. The meaningful question is whether the check captures the requirement and would reveal the defect, not whether it merely exercises the new implementation.
Check effects beyond the changed lines
Inspect authentication, input validation, authorization, error handling, logging, concurrency, and added dependencies as appropriate to the change. Ask whether a public API, database schema, configuration, or compatibility contract has changed.
Use security and dependency checks already appropriate to the repository. Review new packages and their licensing rather than treating an additional dependency as a cost-free implementation detail.
A short diff can affect other modules. Passing tests cover their defined scenarios; they do not prove that every implicit product requirement or production interaction has been considered.
Record what the review actually established
| Evidence | What it establishes | Remaining question |
|---|---|---|
| Code location | Where the proposed issue occurs | Does the wider context support it? |
| Reviewed diff | Which changes are being accepted | Are side effects understood? |
| Command output | Which check ran and its result | Does it cover the real requirement? |
| Human approval | Who accepted the change | Are deployment and recovery ready? |
Keep an independent validation trail
Do not accept a claim that tests ran without supporting output. Distinguish checks executed, checks proposed, and checks left pending. Another developer should be able to understand that distinction without reopening the entire conversation.
For changes involving authentication, payments, personal data, migration, or production behavior, obtain review appropriate to the project. If no automated check exists, document the meaningful manual validation instead of presenting an untested patch as verified.
Record relevant tool settings, commands, and limitations with the change. Approval should identify the actual diff and evidence, not the model’s most polished explanation of it.
Use a bounded daily workflow
Move from issue and acceptance criteria to a controlled branch, minimal context, limited tools, reviewed changes, relevant checks, and responsible approval. Include a recovery route before releasing consequential changes.
For example, a form-validation fix should identify the failing input, preserve expected valid behavior, and verify the response presented to the user. A test that merely confirms the new helper returns a chosen value may miss the actual submission problem.
When reviewing an unfamiliar module, ask the agent to identify the caller and the data contract before proposing a patch. If it cannot establish that context, keep the conclusion tentative. A useful review note can say which scenario was checked and which related path remains untested. That is more actionable than approving a change because its explanation sounds complete, and it gives the next reviewer a specific place to continue.
Frequently asked questions
Can Claude Code edit files?
It can use project tools according to the configured environment and permissions. Limit the scope and inspect the resulting diff.
Should I bypass permissions to make review faster?
Do not make that the default. Establish suitable access and keep consequential commands reviewable.
Do passing tests prove the code is correct?
No. Check the requirements, test coverage, security, compatibility, and effects beyond the immediate patch.
