Littlebird Mail

Littlebird's independent mailbox - a Cloudflare Worker that acts as a remote MCP server for send, read, reply, and search.

What it does

• Outbound: Sends email as [email protected] via Cloudflare's send_email Worker binding. DKIM-signed, so it lands as Littlebird - not Shane.
• Inbound: Receives email via Cloudflare Email Routing, parses with postal-mime, and stores in D1.
• MCP Tools: Six tools exposed over a stateless HTTP endpoint (/mcp):
  • send_email - Send mail as Littlebird
  • reply - Reply to an existing thread
  • list_inbox - Paginated inbox list, optional unread-only filter
  • read_message - Full message body + marks as read
  • search_inbox - Text search across subject, body, and from
  • inbox_stats - Total and unread counts

Architecture

• Stateless: No Durable Objects or session state. All persistence is D1.
• Auth: /mcp is guarded by a Bearer token (MCP_TOKEN secret).
• Threading: Unified messages table with thread_id and in_reply_to. Replies attach to the parent thread.

Deploy

1. Domain setup (alive-node only)

• Onboard workslo.ai to Cloudflare Email Service (Dashboard: Compute & AI > Email Service > Onboard Domain).
• Add SPF + DKIM records as instructed.

2. Install & generate types

npm install
npx wrangler types  # Generates worker-configuration.d.ts with runtime types

3. Deploy

npx wrangler deploy

4. Set secrets

npx wrangler secret put MCP_TOKEN
# Enter a long random string (this guards /mcp)

5. Inbound routing rule

Dashboard: Email Service > Email Routing > Create rule

• Custom address: [email protected]
• Action: Send to a Worker
• Worker: littlebird-mail

6. Wire up the MCP client

In Littlebird Settings > Integrations, add a Remote MCP server:

• URL: https://littlebird-mail.<your-subdomain>.workers.dev/mcp
• Auth: Bearer token = the value you set in step 4

Schema

D1 database littlebird-mail was provisioned manually. If you start fresh, run:

CREATE TABLE IF NOT EXISTS messages (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  direction TEXT NOT NULL, -- 'inbound' or 'outbound'
  from_address TEXT,
  to_address TEXT,
  subject TEXT,
  body_text TEXT,
  body_html TEXT,
  thread_id TEXT,
  in_reply_to TEXT,
  message_id TEXT UNIQUE,
  created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
  read_at DATETIME,
  labels TEXT,
  raw_headers TEXT
);

CREATE INDEX IF NOT EXISTS idx_thread ON messages(thread_id);
CREATE INDEX IF NOT EXISTS idx_created ON messages(created_at);
CREATE INDEX IF NOT EXISTS idx_in_reply_to ON messages(in_reply_to);

CREATE TABLE IF NOT EXISTS config (
  key TEXT PRIMARY KEY,
  value TEXT
);

D1 Database ID

• Name: littlebird-mail
• ID: dbc3a61d-e581-4b03-9296-eee97dfb5851
• Region: WNAM

Environment

Binding	Name	Purpose
D1	DB	Message store + config
send_email	EMAIL	Outbound mail
var	LB_ADDRESS	Default From address
secret	MCP_TOKEN	Bearer auth for /mcp