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    Stripe Webhook & Checkout Doctor

    Stripe Webhook & Checkout Doctor

    by JustHandled Labs

    Diagnose why Stripe Checkout, the Billing Portal, or your webhooks aren't working: missing signature verification, raw-body mistakes, no idempotency, test/live key mix-ups, broken success and cancel URLs, and subscription lifecycle gaps. Works across Next.js, Express, FastAPI, and serverless, with severity, evidence, and copy-paste fixes for each finding.

    Updated Jun 2026
    Security scanned
    Works with Claude Code

    $25

    · or 125 credits

    30-day refund guarantee

    Secure checkout via Stripe

    Included in download

    • Audit webhook signature verification and idempotency logic
    • Fix broken Stripe Checkout success and cancel URL flows
    • terminal, env_vars, file_read automation included
    • Ready for Works with Claude Code
    • Instant install

    Sample input

    My Stripe webhooks are failing in production but work locally. Here are my Express route and the error logs from the dashboard.

    Sample output

    Found 1 Critical Issue:

    • Severity: Critical
    • Issue: Webhook signature verification is using the wrong secret.
    • Evidence: Express route uses process.env.STRIPE_WEBHOOK_SECRET which contains a local 'whsec_' key.
    • Fix: Update production env to use the live endpoint secret.

    About This Skill

    What it does

    Stripe Webhook Checkout Doctor is a specialized diagnostic engine for debugging and auditing Stripe payment integrations. It identifies critical vulnerabilities and logic errors in Stripe Checkout sessions, Billing Portal configurations, and webhook handlers. By analyzing your code, logs, and environment configurations, it provides evidence-backed reports on payment safety and lifecycle management.

    How it works

    The skill uses a multi-step diagnostic workflow: it runs a local heuristic scanner on your repository, cross-references your implementation against a comprehensive audit checklist, and identifies discrepancies in webhook signature verification, idempotency, and subscription state handling. Unlike generic AI prompts, this tool cites exact evidence from your source code and logs to justify its findings.

    Supported Tools & Frameworks

    • Frameworks: Next.js, Express, FastAPI, and generic serverless environments.
    • Languages: Node.js, Python, and TypeScript.
    • Stripe Features: Checkout (One-time & Subscriptions), Billing Portal, and Webhooks.
    • Development: Integrates with Stripe CLI logs for real-time debugging.

    Why use this skill

    Debugging payments is high-stakes; a missed webhook or an insecure signature check can lead to lost revenue or unauthorized access. This skill automates the rigorous 'manual review' process, identifying edge cases like trial-to-subscription transitions and refund handling that developers often overlook. You get formatted remediation snippets and clear verification steps ready for implementation.

    Use Cases

    • Audit webhook signature verification and idempotency logic
    • Fix broken Stripe Checkout success and cancel URL flows
    • Debug subscription lifecycle issues in Next.js or Express apps
    • Verify Stripe Billing Portal configurations and redirect logic
    • Analyze Stripe CLI and server logs to find hidden payment failures

    Reviews

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    Only users who have downloaded or purchased this skill can leave a review.

    Security Scanned

    Passed automated security review

    Permissions

    Terminal / Shell
    Environment Variables
    Read Files

    File Scopes

    stripe-webhook-checkout-doctor/**
    Next.js
    .env.example
    **/*.js
    **/*.ts
    **/*.tsx
    **/*.py
    **/package.json

    Read-only inspection first. The bundled scanner reads matching files and prints markdown or JSON findings. It installs nothing, transmits nothing, and modifies nothing. It does not call the Stripe API or touch your live account. Any write, install, deploy, payment, delete, reset, live-account action, or external network lookup requires explicit user confirmation.

    Tags

    stripe
    payments
    webhooks
    debugging
    node-js
    python

    Works with Claude Code, Codex CLI, Cursor, OpenCode/OpenClaw, Gemini CLI, and other agents that load SKILL.md folders. The bundled scanner uses the Python 3 standard library only and degrades to manual checklist mode when Python or matching project files are unavailable.

    Creator

    JustHandled Labs

    JustHandled Labs creates focused agent skills and workflow packs for Claude, Codex, Cursor, and AI-assisted builders. Each tool is designed around a real repeatable task: cleaner commits, better PRs, stronger handoffs, safer repo hygiene, clearer documentation, and less copy-paste chaos. The goal is not generic AI productivity. The goal is specific workflows that are easier to run, review, and repeat. Maintained by H.J. Westerfield, with a background in communications, editing, project coordination, customer support, and practical AI systems. JustHandled Labs builds tools for people who want useful automation without theatrical complexity.

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