Source: https://codereviewguide.fyi/perch-vs-codereviewbot/

Perch vs CodeReviewBot · reviewed 2026-10-14

# CodeReviewBot alternative for local rule checks

Perch runs from the terminal on the file the agent is editing. Save a behavior rule, select it by name and rerun it after fixing a finding, with no developer seat fee.

`perch check` reads working files; `perch scan` reads Git HEAD. Relevant source is sent to TypeSafe’s hosted models. The MIT CLI does not run model inference offline.

[See the rule catch a regression](https://codereviewguide.fyi/perch-vs-codereviewbot/#check)[Install the Perch CLI](https://github.com/lakeday-org/perch/blob/main/docs/install.md)

## Perch

~50¢

per mid-sized pull request · estimate

- 10¢ per 1,000 fresh rule checks
- Cached checks free
- No seat fees · $5 free usage credit
- MIT CLI · English project rules

**CodeReviewBot**Team Pro starts at $25/month for unlimited private-repository reviews.

Perch estimate: approximately 150 methods read, based on September–October 2026 check density. [Compare billing assumptions](https://codereviewguide.fyi/perch-vs-codereviewbot/#pricing).

**Run it locally**Check uncommitted files

**Keep the rule**Version it with the code

**Read each method**Within the selected parsed scope

**Pay for checks**No per-developer subscription

## Catch the fix an agent removes later.

A saved requirement makes a recurring mistake checkable. In this Perch capture from September 20, 2026, the same rule flags a missing guard and passes after the guard is restored.

### The regression

```
def refund(order, payment):
    payment.refund(order.total)
    order.status = "refunded"
    return order
```

1 check, 1 broken. Refunded orders cannot be refunded again.

### The guarded method

```
def refund(order, payment):
    if order.status == "refunded":
        return order
    payment.refund(order.total)
    order.status = "refunded"
    return order
```

1 check, nothing to report.

Source: [public order-service checkout.py at the linked commit](https://github.com/lakeday-org/perch/blob/4af67af46d76ac99398d61c7ad0a45441760d4dc/test/fixtures/order-service/checkout.py). The captured standalone file is refund.py. [Perch command output and timestamp](https://codereviewguide.fyi/perch-vs-codereviewbot/refund-capture.json). This saved-rule demonstration does not measure CodeReviewBot's detection rate.

## Perch vs CodeReviewBot: what your team runs.

Perch turns project behavior into focused checks that agents can run before committing. Use these differences to choose the review workflow and billing model your team needs.

Published Perch capabilities and CodeReviewBot documentation, reviewed 2026-10-14

| Capability | Perch | CodeReviewBot |
| --- | --- | --- |
| Billing | 10¢ per 1,000 fresh rule checks. Cached checks free. No seat fees. | Team Pro starts at $25/month for unlimited private-repository reviews.[Vendor documentation ↗](https://codereviewbot.ai/) |
| Before commit | perch check reads the files on disk, including uncommitted edits. | GitHub app and browser snippet review; local CLI was not documented.[Vendor documentation ↗](https://codereviewbot.ai/) |
| Custom requirements | English ensure rules in perch.yaml: project, file or method scope. No paid custom-rule tier. | Team custom style and review rules.[Vendor documentation ↗](https://codereviewbot.ai/) |
| Coverage | Each parsed non-test application method in the selected scan scope is read, with caller and callee context. No method-count cap. | Pull-request and code-snippet review.[Vendor documentation ↗](https://codereviewbot.ai/) |
| Open source | MIT-licensed CLI. Hosted model analysis is a paid service. | Commercial review service.[Vendor documentation ↗](https://codereviewbot.ai/) |

## CodeReviewBot alternative for local rule checks

Run the project rule before pushing the change. Perch's shell command reads the working file, reports a broken requirement, and can be rerun after the fix. The MIT CLI and versioned rule make that check reusable across coding agents and CI.

## Review before committing

CodeReviewBot: GitHub app and browser snippet review; local CLI was not documented. [CodeReviewBot workflow documentation](https://codereviewbot.ai/).

Perch reads the current working file with `perch check`. For a known requirement, select its rule name and method instead of requesting another broad review. A local CLI describes where the command runs; Perch sends relevant source to hosted TypeSafe models for analysis.

## How do saved requirements differ?

CodeReviewBot: Team custom style and review rules. [CodeReviewBot rule documentation](https://codereviewbot.ai/).

Perch stores English `ensure` rules in `perch.yaml` or `.perch/rules/`. Project, file and method scopes determine what is checked. Run the named check after an edit and after the repair; a rule finding can fail the command and a CI gate. [Perch rules](https://github.com/lakeday-org/perch/blob/main/docs/rules.md) · [Working-file checks](https://github.com/lakeday-org/perch/blob/main/docs/check.md).

## What does the review bill depend on?

[Compare CodeReviewBot's billing unit and Perch's usage estimate](https://reviewpricing.fyi/codereviewbot/)

## Is the CLI open source and offline?

CodeReviewBot: Commercial review service. [CodeReviewBot product or license source](https://codereviewbot.ai/).

Perch’s CLI is MIT-licensed; hosted model inference is a separate paid service included in its published check rate. It does not run the model offline. Unchanged requests can reuse cached answers for free. Fresh judgments can vary, and a passing requirement check does not prove application correctness. [Perch MIT license](https://github.com/lakeday-org/perch/blob/main/LICENSE).

## When does CodeReviewBot fit the workflow?

CodeReviewBot exposes a GitHub app and browser snippet review. Its free public and limited private review options may fit that workflow; local CLI support was not documented.

## Estimate the review bill

[Perch and CodeReviewBot: pricing, allowances and workload calculator](https://reviewpricing.fyi/codereviewbot/)

## Make the agent check its next edit.

### Install the CLI

```
npm install -g @lakeday/perch
```

[Perch installation and quick start](https://github.com/lakeday-org/perch/blob/main/docs/install.md)

### Save a behavior rule

```
perch rules add refund-once \
  --where refund.py --each method \
  --ensure "Refunded orders cannot be refunded again."
```

The captured rule checks the requirement shown above. [Rule syntax and selectors](https://github.com/lakeday-org/perch/blob/main/docs/rules.md)

### Check the working file

```
perch check refund.py::refund --rules refund-once
```

Run the check after an edit and after the fix. [Working-tree check documentation](https://github.com/lakeday-org/perch/blob/main/docs/check.md)

Use [perch scan](https://github.com/lakeday-org/perch/blob/main/docs/scan.md) for repository code at Git HEAD and [changed-code CI checks](https://github.com/lakeday-org/perch/blob/main/docs/ci.md) for pull requests. New model judgments can vary. Repeatability comes from cached answers for unchanged requests; a pass does not prove application correctness.

## Keep your project requirements checkable.

Choose Perch when you want an MIT CLI, English behavior rules and usage pricing that stays independent of team size. Give your coding agent a saved check it can run after every relevant edit.

[Install Perch](https://github.com/lakeday-org/perch/blob/main/docs/install.md)

## Sources and price details

Published by Perch. Vendor facts were reviewed on 2026-10-14; plans and allowances can change. Vendor marks belong to their owners.

- [codereviewbot.ai/](https://codereviewbot.ai/)

Perch sources and example arithmetic

- [Public CLI source](https://github.com/lakeday-org/perch) · [MIT license](https://github.com/lakeday-org/perch/blob/main/LICENSE)
- [English rules](https://github.com/lakeday-org/perch/blob/main/docs/rules.md) · [Working-tree checks](https://github.com/lakeday-org/perch/blob/main/docs/check.md) · [Method scope and context](https://github.com/lakeday-org/perch/blob/main/docs/scanning.md)
- [Published Perch rate and estimate assumptions](https://codereviewguide.fyi/perch-vs-codereviewbot/pricing-evidence.json)
- [September 20, 2026 refund-rule capture](https://codereviewguide.fyi/perch-vs-codereviewbot/refund-capture.json)

## Compare CodeReviewBot with other review tools

- [CodeRabbit vs CodeReviewBot](https://codereviewguide.fyi/coderabbit-vs-codereviewbot/)

[Full head-to-head library and tool selector](https://codereviewguide.fyi/tool-comparisons/)

**Code Review Guide**

Tools & workflows.

Published by Perch · © 2026 Verglas LLC. Code Review Guide is a Perch publication.

Perch’s MIT license covers the CLI; hosted model analysis is a paid service. Relevant source is sent to the configured model service.

[Perch CLI MIT license](https://github.com/lakeday-org/perch/blob/main/LICENSE) · [Article text](https://codereviewguide.fyi/perch-vs-codereviewbot/index.md) · [Resource index](https://codereviewguide.fyi/llms.txt)