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The API maintenance agent

Self-maintaining
APIs

Mantle detects API changes, updates the code they affect, validates the migration, and opens a verified pull request.

Get started See how it works

Available today for Stripe, in TypeScript and JavaScript repositories

Stripe is the first API Mantle maintains, not the last. More will follow.

Example runacme/payments Verified

  1. 01 · API change

    Stripe

    2026-09-30.endive

    payment_method_types removed from Checkout Session create

    Detected

  2. 02 · Impact analysis

    3 files affected

    • src/payments/checkout.ts
    • src/billing/subscribe.ts
    • src/api/orders.ts

    Traced

  3. 03 · Migration

    Changes prepared

    − payment_method_types

    3 edits in 3 files

    Prepared

  4. 04 · Validation

    • TypecheckPassed
    • LintPassed
    • Tests184 passed
    • BuildPassed

    Passed

  5. 05 · Pull request

    #212

    Update Stripe API integration

    Verified

    Verified

  • GitHub
  • Stripe
  • TypeScript
  • JavaScript

Built around the tools your engineering team already uses.

The problem

APIs change.
Code drifts.

Third-party APIs evolve constantly. Endpoints change. SDK methods are deprecated. Response formats shift. Authentication changes. Every change can turn into another manual engineering task.

Today, by hand

  1. 01API changes
  2. 02Engineer investigates
  3. 03Find impacted code
  4. 04Understand migration
  5. 05Modify code
  6. 06Run tests
  7. 07Open PR
  8. 08Review

With Mantle

  1. 01API changes
  2. 02 · MantleInvestigates, finds the impacted code, migrates it, runs your tests and opens the PR
  3. 03 · Your teamReview

Mantle does the work before it becomes someone’s task.

The Mantle agent

An agent for the work nobody wants to maintain.

Mantle is not an AI coding assistant. It has one job. It watches the APIs your code depends on, starting with Stripe. When one changes, it makes the change in your repository, proves it with your own checks, and hands your team a pull request.

Mantle doesn’t help you write code. It keeps your integrations alive.

Product demo

Watch an integration repair itself.

One Stripe change, from detection to a verified pull request. Played back on a sample repository; press any step to jump to it.

acme/paymentsSample repository Step · 1/5

Step 01 · API change detected

Stripe removed a request parameter.

Stripe changelog2026-09-30.endiveBreaking

Remove support for payment_method_types on Checkout.SessionCreateParams.

Change type
field_removed
SDK call
stripe.checkout.sessions.create()
This repository
Uses this call

Demonstration of product behavior with sample data

Why Mantle

Engineering time belongs to the product.

  1. 01Detect before breakage

    Find API changes before they become emergency debugging.

  2. 02Understand the impact

    Trace changes through the repository instead of hunting for them by hand.

  3. 03Verify before review

    Run your existing engineering checks before the pull request exists.

04Keep humans in control

Mantle proposes and validates changes. Your team decides what gets merged.

Pull request #212 Verified

Update Stripe integration: remove payment_method_types

  • Typecheck
  • Lint
  • Tests 184/184
  • Build
Review required
Mantle opens it. Your team merges it. Mantle never does.

Stop maintaining your Stripe integration by hand.

Get started
NextHow it works