Centralizes Thunderbird email operations as MCP tools: read, send, draft, search, attachments.
Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type @ followed by the MCP server name and your instructions, e.g., "@thunderbird-mcp-server read the last 5 emails from my Inbox"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
Centralizes Thunderbird email operations as MCP tools: read, send, draft, search, attachments.
Aspect | State |
Core development | Complete |
Unit tests | 5/5 PASS |
Deployment | Active (opencode MCP) |
Agent integration |
|
Related MCP server: thunderbird-cli
Tool | Description | Agent access |
| List available Thunderbird mail folders | ✅ read |
| Read messages from a folder with pagination | ✅ read |
| Search messages by keyword | ✅ read |
| Download attachments from a message | ✅ read |
| Create a draft email in Thunderbird | ✅ write |
| Send email via Thunderbird compose command | ❌ forbidden |
Environment variables:
THUNDERBIRD_PROFILE_DIR — Thunderbird profile directory (default: ~/.thunderbird)
THUNDERBIRD_MAIL_DIR — Local mail data directory (default: ~/Downloads/thunderbird.tmp)
THUNDERBIRD_SEND_COMMAND — Command to invoke Thunderbird (default: thunderbird)
THUNDERBIRD_DEFAULT_ACCOUNT — Default account identifier (optional)
THUNDERBIRD_DRAFT_FOLDER — Drafts folder name (default: Drafts)
Due to PEP 668 restrictions, use PYTHONPATH approach:
export PYTHONPATH=src
python3 -m thunderbird_mcp_serverOr use the provided wrapper:
bash run.shDevelopment:
.venv/bin/pip install -e ".[dev]"bash run.sh
# or directly with PYTHONPATH:
PYTHONPATH=src python3 -m thunderbird_mcp_serverPYTHONPATH=src .venv/bin/pytest tests/ -vTest coverage:
test_list_folders — discovers mbox folders from temp mail dir
test_read_messages — parses mbox with verified subject/body extraction
test_search_messages — keyword search across folders
test_list_folders_uses_unique_relative_names — multi-account path dedup
test_modified_utf7_folder_name_decoding — IMAP modified UTF-7 decoding (e.g. Chinese folder names)
Registered in .opencode/opencode.json:
{
"mcp": {
"thunderbird-mcp-server": {
"type": "local",
"command": ["bash", "/home/gw/opt/thunderbird-mcp-server/run.sh"],
"enabled": true,
"environment": {
"THUNDERBIRD_PROFILE_DIR": "/home/gw/snap/thunderbird/common/.thunderbird/34p30y9x.default",
"THUNDERBIRD_MAIL_DIR": "/home/gw/snap/thunderbird/common/.thunderbird/34p30y9x.default/ImapMail",
"THUNDERBIRD_SEND_COMMAND": "/snap/bin/thunderbird"
}
}
}
}Agent integration: communication-drafter is the sole authorized agent, granted read/search/draft tools only. tb_send_message is forbidden at the static check level (scripts/check_agent_tool_budget.py). Sending remains a manual user action.
config.py — ThunderbirdConfig dataclass, reads from env vars
client.py — ThunderbirdClient: reads mbox folders, parses messages, sends via CLI
server.py — MCP Server with 6 tool definitions and stdio transport
tools/ — Shared tool parameter schemas
Large mbox timeout: Folders with thousands of messages (e.g. INBOX) may exceed MCP timeouts during read/search. Mitigation: use limit and offset for pagination, or target smaller subfolders.
Local mbox dependency: Read operations require Thunderbird to have downloaded mail locally (offline storage enabled). Folders with only .msf indexes return placeholder messages.
Send is interactive: tb_send_message opens the Thunderbird compose window; it is not fully automated. This tool is explicitly denied to all agents — sending is a manual user action.
MSF-only folders: Return [MSF index only — no message data] placeholder.
PEP 668: pip install -e . is blocked; use PYTHONPATH=src approach.
tb_send_message denied: Static check in scripts/check_agent_tool_budget.py prevents any agent from being granted this tool.
This server cannot be deployed
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Your mailbox for MCP clients: search, read, draft, send, rules and notes. Sending is off by default.
Your agent needs a mailbox of its own — to receive, thread, draft and send, with attachments, without borrowing your personal inbox or your company's SMTP. **What you can ask for** • "Create an inbox for this agent and tell me its address." • "Read the new messages in this thread and draft a reply." • "Send this message with the attachment and wait for the response." • "Search this inbox for everything from that domain." • "Show delivery metrics and the events on this inbox." **How to use it** Point any MCP client at https://mcp.aisa.one/mail/mcp and sign in with OAuth — there is no key to create or paste. 49 tools: create and delete inboxes, list and read messages, raw message bodies, attachments, threads, drafts and draft attachments, send and reply, message search, inbox events, metrics, and list entries — reads and writes. **Why this rather than the source** A real inbox an agent owns, rather than an SMTP credential it borrows from a human. **It is also a door to the rest** The same login reaches 26 sources and 580+ operations. Find the contact elsewhere in the catalogue, then write to them from here — without adding a second server. **What it costs** Finding and inspecting an operation is free. Running one is billed per call at API prices, with no seat and no monthly minimum, and every call takes max_price_usd so an agent cannot overspend by accident. **Where else it reaches** https://mcp.aisa.one/sales/mcp finds the person to write to.
