Add Resend Email Channel

Connect NanoClaw to email via Resend for async email conversations. NanoClaw doesn't ship channels in trunk — this skill copies the Resend adapter in from the channels branch.

The mechanical steps under Apply carry nc: directive fences: an agent reads the prose and applies them, and a parser can apply them deterministically from the same document. Every directive is idempotent, so the whole skill is safe to re-run; anything a parser can't apply falls back to the prose beside it.

Apply

1. Copy the adapter

Fetch the channels branch and copy the Resend adapter into src/channels/ (overwrite — the branch is canonical):

src/channels/resend.ts
src/channels/resend-registration.test.ts

2. Register the adapter

Append the self-registration import to the channel barrel (skipped if the line is already present). This one line is the skill's only reach-in into core:

import './resend.js';

3. Install the adapter package

Pinned to an exact version — the supply-chain policy rejects ranges and latest:

@resend/chat-sdk-adapter@0.3.0

4. Build and validate

Build guards the typed createChatSdkBridge(...) core call and proves the dependency is installed (the adapter imports @resend/chat-sdk-adapter; if it isn't installed the barrel throws). End-to-end email delivery against a real domain is verified manually once the service runs.

pnpm run build

pnpm exec vitest run src/channels/resend-registration.test.ts

resend-registration.test.ts imports the real channel barrel and asserts the registry contains resend. It goes red if the import line is deleted or drifts, if the barrel fails to evaluate, or if @resend/chat-sdk-adapter isn't installed (the import throws) — so it also covers the dependency from step 3.

Credentials

Resend account and domain setup is human and interactive — these steps are prose, not directives (no parser can verify a sending domain or click through the Resend UI). A recipe rebuild produces a compiling, registered adapter that cannot receive a message until they're done.

1. Go to resend.com and create an account.
2. Add and verify your sending domain.
3. Go to API Keys and create a new key.
4. Set up a webhook:
   • Go to Webhooks > Add webhook.
   • URL: https://your-domain/webhook/resend.
   • Events: select email.received.
   • Copy the signing secret.

Store the credentials

Capture the secrets, then write them. prompt only asks and binds the answer to a name; a separate directive consumes it — so the same prompts could feed ncl or the OneCLI vault instead of .env by swapping only the consumer. Here they go to .env (set-if-absent — a value you've already filled in is never overwritten):

Paste the Resend API key — API Keys, starts with `re_`.

Paste the webhook signing secret — Webhooks, the value you copied above. NanoClaw's webhook server listens on 127.0.0.1 only; if the proxy or tunnel serving that URL runs on another machine or in Docker on Linux, add `WEBHOOK_HOST=0.0.0.0` to `.env` (it takes effect at the next restart).

The bot's sending email address on your verified domain (e.g. `bot@yourdomain.com`).

The display name to send as (e.g. `NanoClaw`).

RESEND_API_KEY={{api_key}}
RESEND_FROM_ADDRESS={{from_address}}
RESEND_FROM_NAME={{from_name}}
RESEND_WEBHOOK_SECRET={{webhook_secret}}

Connect yourself

Because email is direct-addressable, the bot can write to you first — so wire your own address as the owner and have it email you a hello. Tell it your address and which agent should answer your email (ncl groups list shows their folders):

Your email address — I'll wire you as owner and email you a hello.

Which agent should answer your email? Enter its folder (run `ncl groups list`).

Register yourself as the owner, wire your address so the agent answers your email, and send the hello:

ncl users create --id resend:{{owner_email}} --kind resend --display-name Owner
ncl roles grant --user resend:{{owner_email}} --role owner
ncl messaging-groups create --channel-type resend --platform-id resend:{{owner_email}} --is-group 0
ncl wirings create --channel-type resend --platform-id resend:{{owner_email}} --agent-group {{agent_folder}} --engage-mode pattern --engage-pattern .
ncl messaging-groups send --channel-type resend --platform-id resend:{{owner_email}} --sender-id resend:{{owner_email}} --sender Owner --text "Hi — I'm your NanoClaw assistant, reachable by email now. Reply to this thread anytime."

The hello arrives as a fresh email thread; reply to keep the conversation going. Your own address is the conversation key (resend:<your-address>).

Next Steps

If you're in the middle of /setup, return to the setup flow now. (Answering an open inbox — anyone who emails in, not just you — is a separate, not-yet-wired case: email is plain-message, so the router never auto-creates a group for an unknown sender; each correspondent's resend:<their-address> must be wired explicitly.)

Channel Info

• type: resend
• terminology: Resend handles email. The bot has one fixed sending identity (RESEND_FROM_ADDRESS, e.g. bot@yourdomain.com); every external correspondent the bot emails with is a separate conversation, keyed by their address.
• how-to-find-id: The platform ID is the correspondent's email address, prefixed — resend:<their-address> (e.g. resend:you@example.com) — not the bot's from-address. The adapter derives it from the reply-to party (channelIdFromThreadId returns resend:<address>); each distinct email thread from that person (by root Message-ID) is a sub-conversation under it.
• supports-threads: no (the adapter sets supportsThreads: false; replies still thread via email headers, but the router does not treat threads as the primary conversation unit)
• typical-use: Async communication -- email conversations with longer response expectations
• default-isolation: Same agent group if you want your agent to handle email alongside other channels. Separate agent group if email contains sensitive correspondence that shouldn't be accessible from other channels.

Troubleshooting

Sends fail with 401. The API key comes from the Resend dashboard's API Keys page and starts with re_. Keys are shown once at creation — if in doubt, create a new one and update RESEND_API_KEY in .env.

The hello email never lands, or hits spam. The sending domain must show as verified under Resend → Domains — until the SPF/DKIM DNS records propagate, sends are rejected or spam-foldered. RESEND_FROM_ADDRESS must be an address on that verified domain; a free-mail from-address will not work.

Replies never reach the agent. Inbound only flows via the webhook: Resend → Webhooks must point at your public host at /webhook/resend (shared webhook server, port 3000) with the email.received event selected, and RESEND_WEBHOOK_SECRET must match that webhook's signing secret. Resend's webhook page lists delivery attempts — a run of failures means the URL is unreachable or the secret mismatches.

Adapter installed but nothing flows. Run pnpm exec vitest run src/channels/resend-registration.test.ts — red means the barrel import or the @resend/chat-sdk-adapter install drifted, so re-run the Apply steps. If green, restart the service so it loads the adapter and .env, then re-send the hello.

A proxy or tunnel on another machine, or in Docker on Linux, gets connection refused or times out. The webhook server listens on 127.0.0.1 only. Add WEBHOOK_HOST=0.0.0.0 to .env and restart; Webhook server started in logs/nanoclaw.log shows the host it bound.