Email Resend

Send and receive emails using the Resend API. Use for: (1) sending emails directly via Resend API, (2) receiving email notifications via cron, (3) drafting replies with proper threading, (4) downloading attachments from inbound emails. Required env vars: RESEND_API_KEY (API key). Optional env vars: DEFAULT_FROM_EMAIL, DEFAULT_FROM_NAME (fall back to preferences file if not set). License: Apache-2.0 — See LICENSE file for details.

Ivelin Ivanov@ivelin

Install

openclaw skills install @ivelin/email-resend

License

Apache License 2.0 — See LICENSE file for full text.

Email via Resend

Send and receive emails using the Resend API.

Configuration

No config file needed. The skill auto-discovers settings from:

Environment variables — RESEND_API_KEY (required), DEFAULT_FROM_EMAIL/NAME (optional)
Preferences file — memory/email-preferences.md (from_email, from_name, telegram target)
OpenClaw context — channel, chat_id, thread_id (for cron delivery)

Required Environment Variables

bash

export RESEND_API_KEY="re_123456789"        # Resend API key (required)
# DEFAULT_FROM_EMAIL and DEFAULT_FROM_NAME are optional - loaded from preferences file if not set

Preferences File

The skill reads sender info from memory/email-preferences.md:

yaml

---
from_email: you@company.com
from_name: Your Name
telegram:
  target: "CHAT_ID"
  threadId: "THREAD_ID"
---

Scripts check env vars first, then fall back to preferences file.

First-Time Setup

When the skill is first invoked, the sub-agent should:

Check context — OpenClaw context already has:
- context.user.email (from USER.md)
- context.channel (from current session)
- context.chat_id
- context.thread_id (for topics)
Check memory — Use memory_get tool:
- Try: memory_get path="memory/email-preferences.md"
- If not found, ask user to create memory/email-preferences.md (NO fallback scanning)
If missing, ask user — Via chat message (IMPORTANT for cron jobs):
- "Which email should I send from?" (from_email)
- "What's your display name for sent emails?" (from_name)
- "Which channel/topic should I notify you on?" (telegram target + threadId)
Then create memory/email-preferences.md with their answers using the format above.

Commit to memory — Write preferences to persist across sessions:

bash

write path="memory/email-preferences.md" content="---
from_email: $EMAIL
from_name: $NAME
telegram:
  target: \"$CHAT_ID\"
  threadId: \"$THREAD_ID\"
---

# Email Notification Preferences
Saved auto-configured
"

This ensures memory_get finds it in future sessions. Use MD format with YAML frontmatter.

Format (MD with YAML frontmatter):

markdown

---
from_email: you@company.com
from_name: Your Name
telegram:
  target: \"123456789\"
  threadId: \"334\"
---

# Email Notification Preferences
- **Updated:** 2026-01-01
- **Purpose:** Default notification channel for email alerts

Important: Store in memory/email-preferences.md (NOT MEMORY.md) - isolated cron jobs can read this file via memory_get but NOT MEMORY.md.

Context Fields (Available in Sub-Agent)

Field	Source	Example
`user.email`	USER.md	`you@company.com`
`user.name`	USER.md	`Your Name`
`channel`	OpenClaw	from context
`chat_id`	OpenClaw	`123456789`
`thread_id`	OpenClaw	`334`

The skill uses these directly from OpenClaw context — no parsing needed.

Usage

Inbound (Receive)

Cron Setup

There are two ways to configure the cron:

Option 1: Static (Hardcoded Target)

Use this if you always want the same delivery target:

bash

openclaw cron add \
  --name "email-resend-inbound" \
  --cron "*/15 * * * *" \
  --message "Follow instructions in skills/email-resend/cron-prompts/email-inbound.md exactly. If new emails found, include them in your reply." \
  --session isolated \
  --announce \
  --channel telegram \
  --to "-1003748898773:topic:334"

Option 2: Dynamic (From Preferences) — Recommended

This reads your notification preferences from memory/email-preferences.md and configures the cron automatically.

Run:

bash

python3 ~/.openclaw/workspace/skills/email-resend/scripts/configure-cron.py

What it does:

Reads memory/email-preferences.md for your telegram target/threadId
Deletes any existing email-resend-inbound cron
Creates a new cron with your preferred delivery target

First-time setup: If preferences don't exist, it will tell you what to configure.

Parameters:

--schedule "cron */15 * * * *" — Run every 15 minutes
--session isolated — Required for agentTurn payloads
--announce — Enable delivery of results to chat
--channel telegram — Delivery channel
--to — Telegram target (format: chat_id:topic:thread_id)

Note: The cron prompt reads notification preferences from memory/email-preferences.md. On first run, if preferences are missing, it will ask you for:

Which channel for notifications (telegram, discord, etc.)
Chat ID and Thread ID (for topics)

Manual Check

bash

python3 ~/.openclaw/workspace/skills/email-resend/scripts/inbound.py

Notification Format

Each new email triggers a notification with:

From, Subject, Date
Body preview (~2000 chars)
Attachment list (if any)
Importance: 🔥 HIGH / 📅 MEETING / 📬 NORMAL

Acknowledge Flow (CRITICAL)

NEVER auto-acknowledge emails. Only the user can acknowledge by:

Replying to the notification message, OR
Typing: done / ack

Emails must remain in pending state until user explicitly acknowledges.

Use draft-reply.py to compose replies with proper quoting.

Important: Always use inline replies ([[reply_to_current]]) to keep messages linked in the thread. This enables:

Proper custody chain tracking
Reply-to-email tracing
Better conversation flow

CRITICAL: When responding via OpenClaw message tool, use replyTo parameter (not [[reply_to_current]] tag):

python

message(action="send", channel="<from-context>", replyTo="<msg_id>", ...)

Scripts

Script	Purpose
`inbound.py`	Check emails, send notifications
`draft-reply.py`	Draft reply workflow with quoting & threading
`outbound.py`	Send emails directly
`download_attachment.py`	Download attachments from inbound emails

Downloading Attachments

To download attachments from an inbound email:

bash

# List attachments (shows IDs)
python3 scripts/download_attachment.py <email_id> --list

# Download all to directory
python3 scripts/download_attachment.py <email_id> --output-dir ./attachments

# Download specific attachment
python3 scripts/download_attachment.py <email_id> --attachment-id <attachment_id>

Note: The API path is /emails/receiving/{email_id}/attachments (not the standard /emails/ path).

State Files

memory/email-resend-inbound-notified.json — pending/acknowledged emails
memory/email-message-map.json — notification message_id → email_id (legacy)
memory/email-custody-chain.json — Full DAG of email → notification → actions
memory/email-msg-to-chain.json — notification message_id → chain lookup
memory/email-draft-state.json — Active draft state (email_id, status, reply_content)

See docs/custody-chain.md for DAG design.

Outbound (Send)

bash

python3 ~/.openclaw/workspace/skills/email-resend/scripts/outbound.py \
  --to "recipient@example.com" \
  --subject "Hello" \
  --body "Message text"

# With attachments
python3 ~/.openclaw/workspace/skills/email-resend/scripts/outbound.py \
  --to "recipient@example.com" \
  --subject "Here's the file" \
  --body "See attachment" \
  --attachment ./file.pdf \
  --attachment ./image.png

⚠️ CRITICAL: Email Threading Rule (2026-02-22)

MANDATORY: Always use draft-reply.py for replying to emails.

This is non-negotiable. Failure to follow this rule will result in broken Gmail threading.

Why This Matters

Gmail threads emails based on In-Reply-To AND References headers
Using wrong headers = reply appears as NEW thread = context lost
There's no way to fix this after sending

✅ Correct Workflow (ALWAYS USE THIS)

bash

# Step 1: Start draft (fetches Message-ID automatically)
python3 ~/.openclaw/workspace/skills/email-resend/scripts/draft-reply.py start <email_id>

# Step 2: Set reply content
python3 ~/.openclaw/workspace/skills/email-resend/scripts/draft-reply.py content "Your reply"

# Step 3: Send
python3 ~/.openclaw/workspace/skills/email-resend/scripts/draft-reply.py send

⚠️ CRITICAL: Approval Execution Rule (2026-02-22)

When user approves a draft, you MUST execute the send command immediately.

The mistake to avoid:

❌ Show draft for approval → User says "send" → Only acknowledge, don't execute
✅ Show draft for approval → User says "send" → RUN draft-reply.py send → Then confirm

Correct workflow:

text

1. Show draft for approval
2. User replies "approve", "send", "yes", or "ok"
3. IMMEDIATELY run: draft-reply.py send
4. Only THEN confirm to user

Never:

Only acknowledge the approval without executing
Ask for confirmation after user already approved
Wait to send - do it immediately

❌ NEVER Do These Things

NEVER use outbound.py for replies:

bash

# WRONG - will break threading
python3 ~/.openclaw/workspace/skills/email-resend/scripts/outbound.py \
  --to "x@y.com" --subject "Re: Original" --body "Reply"

NEVER manually construct --reply-to flags:

bash

# WRONG - guessing Message-ID format never works
python3 ~/.openclaw/workspace/skills/email-resend/scripts/outbound.py \
  --to "x@y.com" --subject "Re: Original" --body "Reply" \
  --reply-to "<some-guess>@resend"

NEVER skip the workflow when subject starts with "Re:":

bash

# WRONG - replying without threading headers breaks thread
python3 ~/.openclaw/workspace/skills/email-resend/scripts/outbound.py \
  --to "x@y.com" --subject "Re: Previous Thread" --body "Quick reply"

outbound.py Only For New Emails

outbound.py is for new emails only (not replies):

First contact
Announcements
Emails where you intentionally want a NEW thread

For anything that could be a reply, use draft-reply.py.

Requirements

RESEND_API_KEY environment variable set
Python requests library

Draft Reply Best Practices

When composing a reply via draft-reply.py:

Always quote the original — Include the original message with > prefix so recipient knows what you're responding to
Use proper threading — Set In-Reply-To and References headers using the original email's Message-ID
Keep subject line — Start with Re: prefix to maintain thread (but avoid "Re: Re:")

Structure:

text

Your reply here

---

On [date] [original sender] wrote:
> quoted original message
> continues here

Multiple replies supported — After sending, draft is marked as "sent" so you can reply again to the same thread. Use resume command to continue.
No double Re: — If original subject already starts with "Re:", don't add another
Custody Chain — Track full lineage:
- Email → notification → All replies/actions
- DAG structure with parent links
- Any message traces back to original email

Draft Reply Commands

Command	Purpose
`start <email_id>`	Start a draft reply to an email
`resume`	Continue a sent thread to reply again
`content "text"`	Set reply content
`send`	Send the reply
`cancel`	Cancel the draft
`status`	Show current draft status

After sending, use resume to reply again to the same thread — threading headers are preserved.

Run tests:

bash

python3 skills/email-resend/tests/test_inbound.py

Expected: 43+ tests total (test_inbound.py: 37, test_threading.py: 6, test_attachments.py: varies).

If tests fail:

Check which test failed and why
Fix the feature/code to match expected behavior
Or update tests if feature intentionally changed

⚠️ Privacy & Security Considerations

Required Credentials

RESEND_API_KEY — Required. Get from https://resend.com API settings. Create with minimal permissions.
DEFAULT_FROM_EMAIL / DEFAULT_FROM_NAME — Optional. If not set, loaded from memory/email-preferences.md.

Memory File Access

The skill reads ONLY from explicit preferences file:

memory/email-preferences.md — Required for telegram target/threadId
No fallback scanning of MEMORY.md, USER.md, TOOLS.md, or memory/*.md

This restricted approach prevents information leakage from sensitive files.

Cron Job

The configure-cron.py script will create/delete a cron job named email-resend-inbound via OpenClaw CLI.

Recommendations

Run tests with a dummy RESEND_API_KEY before enabling in production
If you only need outbound email, don't enable inbound/cron
Audit memory/email-preferences.md to ensure it contains only necessary fields
Keep preferences file minimal - only include required fields (target, threadId)

Email Resend

Install

License

Email via Resend

Configuration

Required Environment Variables

Preferences File

First-Time Setup

Context Fields (Available in Sub-Agent)

Usage

Inbound (Receive)

Cron Setup

Option 1: Static (Hardcoded Target)

Option 2: Dynamic (From Preferences) — Recommended

Manual Check

Notification Format

Acknowledge Flow (CRITICAL)

Scripts

Downloading Attachments

State Files

Outbound (Send)

⚠️ CRITICAL: Email Threading Rule (2026-02-22)

Why This Matters

✅ Correct Workflow (ALWAYS USE THIS)

⚠️ CRITICAL: Approval Execution Rule (2026-02-22)

❌ NEVER Do These Things

outbound.py Only For New Emails

Requirements

Draft Reply Best Practices

Draft Reply Commands

⚠️ Privacy & Security Considerations

Required Credentials

Memory File Access

Cron Job

Recommendations

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