Skip to content
Get packs

Guide · Agent skill

How to use the Resend email channel agent skill (add-resend)

Updated · written with AI from the project's own documentation and checked against our catalogue data

The add-resend skill is an installation recipe for NanoClaw, a personal AI assistant framework. It adds a Resend email adapter to your NanoClaw project so the assistant can send and receive email, with each correspondent treated as a separate conversation. This guide explains what agent skills are, how to install this one, how to trigger it with plain requests, and what it needs and risks before you start.

Resend Email Channel Setupnanocoai/nanoclaw · MIT

Quick start

  1. 1Get the skill. Download the add-resend ZIP from this page and unzip it into ~/.claude/skills/ or into your project's .claude/skills/ folder.
  2. 2Prepare NanoClaw and Resend. Make sure you have a NanoClaw checkout with the channels branch, pnpm installed, and a Resend account with a verified sending domain and an API key.
  3. 3Ask the agent to run the skill. In your NanoClaw project, ask the agent in plain language to set up the Resend email channel using add-resend.
  4. 4Configure the Resend webhook. Point a Resend webhook at your public URL ending in /webhook/resend, select the email.received event, and copy the signing secret.
  5. 5Store credentials and connect your address. Give the agent your API key, webhook secret, from address and name when asked, then provide your own email to receive the hello.
  6. 6Restart and test. Restart the NanoClaw service so it loads the adapter and .env, confirm the hello arrives, and reply to check that messages reach the agent.

What is an agent skill and what does add-resend do?

An agent skill is a folder of instructions that an AI agent can read and follow to carry out a specific task. This one is named add-resend and is described as adding a Resend (email) channel integration via Chat SDK.

NanoClaw does not ship with email support in its main code. The skill copies the Resend adapter in from the channels branch of the project, registers it, installs a pinned adapter package, builds and tests the code, and then walks you through storing a Resend API key and webhook secret in the .env file.

  • Copies src/channels/resend.ts and a registration test into src/channels/
  • Appends one import line to src/channels/index.ts
  • Installs the @resend/chat-sdk-adapter package at an exact pinned version
  • Runs a build and a test, then guides credential and webhook setup
  • Optionally wires your own email address as the owner so the assistant emails you a hello

How do you install the add-resend skill?

Download the ZIP for the skill from this page. The archive contains SKILL.md, REMOVE.md and apply-fixtures.json.

To make it available to Claude Code for all your projects, unzip the folder into ~/.claude/skills/. To limit it to a single project, unzip it into that project's .claude/skills/ folder instead.

If you use the Claude apps rather than Claude Code, upload the skill under Settings, then Capabilities, then Skills.

  • Personal install: ~/.claude/skills/
  • Project install: the project's .claude/skills/ folder
  • Claude apps: Settings → Capabilities → Skills

How do you trigger the skill with a natural request?

You do not need a special command. Ask the agent in plain language, inside your NanoClaw project, to add email or Resend support. The agent should match your request to the skill's description and follow its steps.

Be specific about the goal. Say that you want the assistant reachable by email through Resend, and mention whether you already have a Resend account and verified domain. The skill's own prose covers the parts a human must do, so the agent will tell you when it needs your input.

  • Example: Set up the Resend email channel so I can email the assistant.
  • Example: Add Resend email to NanoClaw using the add-resend skill.
  • Example: Walk me through connecting email with Resend and store my API key in .env.

What do the setup steps do?

The mechanical steps are applied in order. Each one is designed to be safe to re-run, so running the skill again will not duplicate changes.

After the build, the test checks that the channel registry contains resend. The test fails if the import line is removed, if the barrel fails to load, or if the Resend adapter package is not installed. End-to-end delivery against a real domain is checked manually once the service runs.

  • Step 1: copy the adapter files from the channels branch into src/channels/ (existing files are overwritten)
  • Step 2: add the self-registration import to src/channels/index.ts if it is not already there
  • Step 3: install the pinned @resend/chat-sdk-adapter package
  • Step 4: run the build and the registration test
pnpm run build

How do you set up Resend and store the credentials?

Resend account and domain setup is done by you in the Resend dashboard. The agent cannot verify a sending domain or click through the Resend interface. Until these steps are complete, the adapter is registered but cannot receive messages.

The agent will then ask for your API key, webhook signing secret, sending address and display name. It writes them to .env only if those variables are not already set, so a value you have filled in is never overwritten.

  • Create an account at resend.com
  • Add and verify your sending domain
  • Go to API Keys and create a new key; it starts with re_ and is shown only once
  • Go to Webhooks, then Add webhook, with the URL https://your-domain/webhook/resend and the email.received event selected
  • Copy the webhook signing secret
  • The from address must be on your verified domain, for example bot@yourdomain.com

How do you connect your own email and test it?

The skill can register your address as the owner and have the assistant email you a short hello. You will need to give your email address and the folder name of the agent that should answer. Run ncl groups list to see folder names.

Your address becomes the conversation key, in the form resend:your-address. The hello arrives as a new email thread, and replying to it keeps the conversation going. Restart the service after setup so it loads the adapter and .env.

  • If the hello never arrives or lands in spam, confirm the domain is verified and the from address is on it
  • If replies never reach the agent, check the webhook URL, the email.received event and that the secret matches
  • Use the test command from the setup section to confirm the adapter is registered
ncl groups list

What people use it for

  • Giving a personal assistant an email address that you can write to from any mail client
  • Running longer, asynchronous conversations with an agent that replies when it has finished work
  • Keeping sensitive email correspondence in its own agent group, separate from your chat channels

Frequently asked questions

How do I install the add-resend skill?

Download the ZIP from this page and unzip it into ~/.claude/skills/ for all projects, or into a project's .claude/skills/ folder for one project. In the Claude apps you can instead upload it under Settings, then Capabilities, then Skills.

What do I need before using the Resend skill?

You need a NanoClaw project checkout with the channels branch, pnpm for the build and test commands, a Resend account with a verified sending domain, a Resend API key starting with re_, a webhook signing secret, and a public URL that reaches the local webhook server.

Is the add-resend skill free to use?

The skill is published under the MIT licence. The source does not describe pricing for Resend, so check Resend's own site for its plans before you rely on it.

Why can the bot not receive email?

Inbound email only arrives through the webhook. Check that the Resend webhook points at your public host at /webhook/resend, that the email.received event is selected, and that the signing secret matches RESEND_WEBHOOK_SECRET. Resend's webhook page lists delivery attempts, which helps find failures.

Why do my sends fail with a 401 error?

A 401 usually means the API key is wrong. Keys come from the API Keys page in Resend and start with re_. Because keys are shown only once, create a new one if you are unsure and update RESEND_API_KEY in .env.

Can anyone who emails the bot reach the agent?

Yes. The skill notes that an open inbox is a separate, not-yet-wired case, and unknown senders are not added automatically. Each correspondent must be wired explicitly, and mixing email with other channels could expose private content unless the agent group is isolated.

New agent skills, repos and AI tools — every week

The best new skills and open-source projects, the fastest-growing repos, and one free prompt. Five minutes to read. Unsubscribe anytime.

Our verdict

Use add-resend if you run NanoClaw, own a domain you can verify with Resend, and are comfortable running build commands and editing configuration. Pick something else if you do not have a domain you control, need a simple chat-based assistant, or handle sensitive mail that should stay away from your other channels.

Download the skill