Webhook Relay Skills

Agent Skills that teach Claude (and other skill-aware agents) how to drive Webhook Relay with MCP tools when available, falling back to the relay CLI/API only when an MCP server is not connected or a local runtime process is required — forwarding webhooks, transforming them, exposing services over tunnels, scheduling recurring webhooks, and receiving/parsing inbound email.

Install all skills

With the skills CLI:

npx skills add webhookrelay/skills

Add -g to install globally for all your agents. You can also use this repo as a Claude Code plugin marketplace (see .claude-plugin/marketplace.json), or copy any skills/<name>/ folder into your agent's skills directory. To install just one skill, use the --skill <name> command shown in each section below.

Skills

webhook-debug

Capture and inspect webhooks with a free, no-signup bin at https://bin.webhookrelay.com — a public URL that records any HTTP request sent to it. See the exact method, headers, query and body a provider sends, stream new requests live, mock the response the bin returns (status/body/headers/delay/failures), and verify HMAC signatures. No relay CLI, account, or API key required — just curl. A great first stop before wiring up forwarding to a real destination.

npx skills add webhookrelay/skills --skill webhook-debug

webhook-forwarding-internal

Receive webhooks from external providers (Stripe, GitHub, Shopify, CI systems, etc.) on a public Webhook Relay endpoint and forward them to a destination that has no public IP — localhost, a private LAN host, or a Kubernetes service. The relay agent holds the outbound connection and performs the final hop, so no inbound firewall ports are needed. Best for local development and testing provider webhooks against code running on your machine.

npx skills add webhookrelay/skills --skill webhook-forwarding-internal

webhook-forwarding-public

Forward webhooks server-side from a public Webhook Relay endpoint to another internet-reachable URL — no local agent required. Use it to relay between cloud services, put a stable URL in front of an API, fan one webhook out to many destinations, or transform payloads in transit (e.g. into Slack/Discord format).

npx skills add webhookrelay/skills --skill webhook-forwarding-public

webhook-transformations

Write, test, and attach JavaScript (or Lua) functions that modify webhooks in flight — reshape the JSON body, rename/format fields, add/remove headers, change the method or path, set the response, drop requests conditionally, or call other HTTP APIs. Covers the function API, MCP-based testing/deployment when available, CLI fallbacks, and attaching functions to inputs/outputs.

npx skills add webhookrelay/skills --skill webhook-transformations

relay-tunnels

Expose a local or internal HTTP/TCP service on a stable public hostname (an ngrok-style reverse proxy) without opening firewall ports — share a dev server, demo a local web app, expose an internal API, or tunnel TCP (SSH, databases). Covers TLS modes, regions, basic auth, host-header rewriting, and running the agent as a service.

npx skills add webhookrelay/skills --skill relay-tunnels

recurring-webhooks

Schedule cron-driven webhooks that fire automatically — send a recurring HTTP request (method, body, headers) to one or more destinations on an interval or at specific times/timezone. Use for health checks, heartbeats, scheduled reports, or triggering a transformation function on a timer. Managed via the relay cron command or the /v1/crons API.

npx skills add webhookrelay/skills --skill recurring-webhooks

temporary-email

Create a disposable / temporary inbound email address from the terminal and read the mail it receives as JSON — no mailbox, SMTP server, or per-address signup. Grab a throwaway inbox for a signup / OTP / confirmation link, receive one-off mail in a script or test, or watch an address for incoming messages. Built on relay email create and the relay events pull-delivery queue.

npx skills add webhookrelay/skills --skill temporary-email

email-parsing-api

Turn inbound email into structured JSON. Create an inbound address and every message is parsed into a stable payload (from, to/cc arrays, subject, text, html, headers, spf/dkim/dmarc, attachments), then delivered to your endpoint or pulled from the events API — an "email → JSON" API without running SMTP/IMAP.

npx skills add webhookrelay/skills --skill email-parsing-api

transform-email-to-api-call

Turn inbound emails into calls to your own API: a bucket with an email address, a public output pointing at your API, and a JavaScript function that reshapes the parsed email into exactly the request your endpoint expects. Email-driven automation — create a ticket/lead/record from an email, or adapt inbound mail to any API shape.

npx skills add webhookrelay/skills --skill transform-email-to-api-call

Tooling preference

When the Webhook Relay MCP server is available, use it first for account and configuration work: listing buckets/functions/logs, creating buckets, inputs and outputs, creating/testing/attaching transform functions, setting rules, and inspecting delivery logs.

Use the relay CLI only when it is genuinely needed:

• running a local relay agent for internal/private destinations
• exposing local services over tunnels
• using a capability that is not exposed by the connected MCP tools
• no MCP server is connected, but relay is authenticated and working

Before falling back to the CLI for configuration, confirm the MCP path is unavailable. If both MCP and CLI are used, keep them pointed at the same account and avoid recreating configuration in a second context.

CLI Prerequisites

For CLI fallback or agent/tunnel runtime work:

1. Install it: https://webhookrelay.com/docs/installation/cli
2. Log in: relay login (or set RELAY_KEY / RELAY_SECRET).
3. Verify: relay bucket ls.

Concepts at a glance

• Bucket — groups inputs and outputs.
• Input — a public HTTPS endpoint that receives webhooks.
• Output — a destination requests are relayed to; internal (delivered by a running agent, e.g. localhost) or public (delivered server-side).
• Function — server-side JavaScript/Lua that transforms requests/responses.
• Tunnel — a public hostname that proxies inbound HTTP/TCP to a local/ internal service.
• Cron — a scheduled, recurring webhook.

Links

• Docs: https://webhookrelay.com/docs
• Functions reference: https://webhookrelay.com/docs/webhooks/functions
• Cron webhooks: https://webhookrelay.com/cron
• Dashboard: https://my.webhookrelay.com
• LLM-friendly docs index (append .md to any docs URL for plain markdown): https://webhookrelay.com/llms.txt

Each skill's References section links the relevant docs as .md URLs that render as plain markdown — handy for agents to fetch and read directly.