Aikido comparison for custom application behavior checks

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.

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

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

Source: public order-service checkout.py at the linked commit. The captured standalone file is refund.py. Perch command output and timestamp. This saved-rule demonstration does not measure Aikido Security's detection rate.

Perch vs Aikido Security: 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.

Aikido comparison for custom application behavior checks

Aikido bundles extensive application-security coverage. Perch offers a small, direct bill for project behavior checks: 10¢ per 1,000 fresh checks, cached checks free. Add a saved requirement to the agent's edit loop without changing the team's security-platform subscription.

Review before committing

Aikido Security: CLI scans code, dependencies, IaC and secrets. Aikido Security workflow documentation.

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?

Aikido Security: English AI custom code rules and security configuration. Aikido Security rule documentation.

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 · Working-file checks.

What does the review bill depend on?

Compare Aikido Security's billing unit and Perch's usage estimate

Is the CLI open source and offline?

Aikido Security: Commercial platform. Aikido Security product or license source.

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.

When does Aikido Security fit the workflow?

Aikido covers a much broader AppSec surface, including dependencies, secrets, infrastructure and runtime protections. Its free plan can fit a small team; Perch is not presented as a replacement for that security bundle.

Estimate the review bill

Perch and Aikido Security: pricing, allowances and workload calculator

Make the agent check its next edit.

npm install -g @lakeday/perch

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

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

Use perch scan for repository code at Git HEAD and changed-code CI checks for pull requests. New model judgments can vary. Repeatability comes from cached answers for unchanged requests; a pass does not prove application correctness.