Webhook Inspector: Debug Third-Party Integrations Without a Server

The webhook debugging pain\n\nThird-party webhooks are fire-and-forget POSTs your code needs to handle correctly on the first try. No retry console, no request history, no local dev mode. You set up ngrok, point the provider at it, and hope.\n\n## The flow that actually works\n\n1. Capture the webhook at an inspector URL\n2. Store the full request (headers, body, timestamp, IP)\n3. Replay it against localhost as many times as you need\n4. Delete the test inbox when you're done\n\n## The free hosted inspector\n\n``bash\n# 1. Create an inbox\ncurl -X POST https://api.lazy-mac.com/webhook-inspector/api/v1/create\n# → { inbox_id: 'w_abc123', url: 'https://api.lazy-mac.com/webhook-inspector/w/w_abc123' }\n\n# 2. Point Stripe/GitHub/Slack at that URL\n\n# 3. List received requests\ncurl 'https://api.lazy-mac.com/webhook-inspector/api/v1/inbox/w_abc123'\n# → { requests: [...] }\n\n# 4. Replay against local\ncurl -X POST 'https://api.lazy-mac.com/webhook-inspector/api/v1/replay' \\\n -d '{\"inbox_id\":\"w_abc123\",\"request_id\":42,\"target\":\"http://localhost:3000/webhooks/stripe\"}'\n`\n\nKV-backed persistent inbox, sub-100ms edge capture, zero local setup.\n\nFree 100/day. Pro $9.99/mo unlimited — much cheaper than requestbin.com's $79/mo.\n\n## Signature verification replay\n\nStripe webhooks have signatures that depend on the raw payload. For replay, you need to preserve bytes exactly — many proxies corrupt this. The lazymac inspector stores raw bytes and replays them verbatim so signature verification still works.\n\n## Companion: MCP integration\n\n`bash\nnpx -y @lazymac/mcp\n> Create a webhook inbox and tell me the URL to paste into Stripe dashboard\n> Replay the last Stripe webhook against http://localhost:3000/webhook\n``

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