The best AI code review tool is the one your team still reads after a month.
Most tools can find a plausible bug in a clean demo. The harder test is whether they find useful issues in your repository without filling every pull request with guesses, summaries and style comments.
We make Scopy, so this is not a neutral list. I have linked to each product and kept the comparison on facts you can test: what it reviews, how it gets context, where it runs and how much control it gives your team.
The short list
| Tool | Best fit | Main trade-off |
|---|---|---|
| GitHub Copilot | Teams that want review built into GitHub | GitHub controls the model and service |
| CodeRabbit | Teams that want a broad, polished PR assistant | Closed cloud service with a lot of output |
| Qodo | Larger teams that want rules and multi-agent review | More setup and product surface |
| Greptile | Teams that care about codebase context | Closed cloud service |
| Bito | Teams that use GitHub, GitLab or Bitbucket | Broad feature set takes time to tune |
| PR-Agent | Teams that want an open-source base to adapt | You own more of the setup and operation |
| Scopy | GitHub teams that want fewer verified findings and self-hosting | GitHub only |
GitHub Copilot code review
GitHub Copilot has the lowest setup cost for a team that already uses GitHub. You can request a review on a pull request or configure automatic reviews with repository rulesets.
GitHub says Copilot can gather full-project context. It can also use repository instructions, AGENTS.md, skills and configured MCP servers. The agentic context work runs through GitHub Actions. A review falls back to a more limited mode when those runner-backed features are not available.
Copilot is a good default when you want a broad first pass and do not want another GitHub App. It can suggest changes that the author applies from the pull request.
GitHub chooses the model, excludes some file types and does not count the review as a human approval. Usage can include both AI credits and GitHub Actions minutes. Our full Copilot code review guide covers those details.
Copilot fits teams that value native setup more than model choice, self-hosting or access to the review pipeline.
CodeRabbit
CodeRabbit reviews pull requests on GitHub and other Git providers. It posts inline findings and a walkthrough that summarizes the change. The product also includes chat, commands and ways to ask for another review.
The experience is polished. A small team can install it and get feedback without building a workflow. That is a real advantage. Review tools fail when authors forget to run them or the results arrive outside the pull request.
CodeRabbit also produces more than bug comments. Some teams like the summaries and walkthroughs. Others only want findings that can change a merge decision. Run it on your own pull requests and count what people act on.
CodeRabbit is a managed cloud product. If your code must stay on your infrastructure, read the open-source CodeRabbit alternatives before you test it.
CodeRabbit fits teams that want a broad PR assistant and prefer a managed service over operating the review stack.
Qodo
Qodo's current code review product uses multiple agents, repository context and a rule system. It reviews pull requests and applies team rules during the review. The older open-source PR-Agent project now points users toward the Qodo product for the current hosted experience.
Qodo is a good fit for an organization that wants one product to cover review, rules and other pull-request work across several Git providers. The extra range also means there is more to configure and evaluate.
Do not treat “multi-agent” as proof of better findings. Several model calls can repeat the same bad assumption. Test whether the final comment points to evidence in the repository and whether the suggested fix survives the test suite.
Qodo makes sense when policy controls and support for several Git platforms matter more than a small review surface.
Greptile
Greptile sells codebase context as its main strength. It builds an understanding of the repository and uses that context when it reviews each pull request.
That is useful because many bugs do not live in the changed lines. A renamed field can break a serializer in another package. A new database query can miss a tenant condition defined in a shared helper. A diff-only reviewer has no chance if it never reads those files.
Context retrieval still needs a test. Ask which files supported a finding and check whether the reviewer found the right contract. More context can reduce guesses, but only when the system selects the relevant parts.
Greptile is worth a test when repository context is the main requirement and a managed cloud service fits your security rules.
Bito
Bito reviews pull requests on GitHub, GitLab and Bitbucket. It can also review changes in supported IDEs. Its Git review product includes repository context, custom guidelines, file filters, incremental reviews and different feedback modes.
The “Essential” mode puts critical issues inline and moves other points into the summary. That gives teams a direct way to reduce comment noise without turning the reviewer off.
Bito is worth testing when developers want the same review system before and after they open a pull request. The product has many controls, so assign someone to tune them. Default settings rarely match a team's real tolerance for review comments.
Bito suits teams that need several Git providers or want review inside the IDE as well as the pull request.
PR-Agent
PR-Agent is the open-source project behind the earlier Qodo Merge product. You can run it as a GitHub App, GitHub Action, GitLab webhook or Bitbucket App. It includes tools for review, code suggestions, PR descriptions and other pull-request tasks.
It gives a platform team a useful base without forcing the team to write the whole integration. You can inspect its code, choose model settings and adapt the workflow.
The cost is ownership. Someone must deploy it, protect model keys, update it and tune the output. Open source removes a vendor limit, but it adds an operating job.
PR-Agent suits a platform team that values control and adaptation more than a ready-made hosted experience.
Scopy
Scopy is our open-source GitHub reviewer. It reads beyond the diff, checks official library documentation when API behavior matters and runs a separate verification pass before it posts a finding.
The design goal is a quiet pull request. Scopy skips style comments and small suggestions unless they affect correctness or security. Teams can write review rules in plain language. They can use hosted Scopy or self-host the stack with their own model provider.
Scopy supports GitHub only. It focuses on defect review rather than PR summaries, planning or coding tools.
Scopy fits GitHub teams that want verified bug findings, repository context and the option to inspect or host the review pipeline.
How to test the tools
Pick two candidates, then run them on the same 20 to 40 historical pull requests. Include clean changes as well as pull requests with known bugs. A set made only from broken code rewards tools that comment on everything.
Record five numbers:
- Known bugs found
- Useful new bugs found
- Wrong or unsupported findings
- Minutes spent checking comments
- Time until the first useful comment
Also record what each tool could not review. Dependency files, generated code, very large changes and private documentation often need separate controls.
The ratio between useful findings and dismissed comments matters more than the total comment count. A reviewer that finds one real bug and posts one wrong claim may be more useful than a reviewer that finds two bugs inside twenty comments.
Use the PR risk analyzer to pick a mix of small and large pull requests for the test. Keep human approval, tests, linters, dependency scanning and security checks in place during the trial.
Start with Copilot if native GitHub setup is the main requirement. Test CodeRabbit or Qodo if you want a wider PR assistant. Test Greptile when repository context is the deciding factor. Test Bito for a workflow that spans Git providers and IDEs. Test PR-Agent or Scopy when open source and self-hosting matter.