Lettio MCP
NPM · @LETTIO/MCP · 2 COMPONENTS · SCANNED SEP 25
Private, EU-hosted email for AI agents over JMAP: read, search, reply, organize, send.
Available components
How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. How we score → Why this is hard to score →
Supply Chain Security98
- No malware found by supply-chain analysis.Pass
- No known CVEs affecting this package version or its production dependencies.Pass
- No install/post-install scripts declared.Pass
- 31 of 96 dependencies flagged as unhealthy. View diagnostics → Partial
Provenance & Transparency45
- Source repository is publicly reachable at the declared URL. View diagnostics → Pass
- Provenance check failed: no build-provenance attestation is published. See how to fix → View diagnostics → Fail
- Clear OSI-approved license (MIT).Pass
- Actively maintained (last published 9 days ago).Pass
- Disclosure check failed: no security disclosure policy was found in the source repository. See how to fix → Fail
Schema Quality & AI Usability82
- AI-judged instruction clarity (excellent).Pass
- Tool/resource definitions use about 626 tokens (~62/item across 10 items; 10 tools + 0 resources), lean.Pass
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management33
- Stability observed for 10 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
Tool Safety75
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- 0 of 1 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation; "send_email" implies "send" and declares no destructiveHint at all, which the MCP spec reads as destructive by default. See how to fix → Fail
- An AI judge read all 10 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
How do I install the Lettio MCP server?
Lettio MCP runs locally as an npm package, launched with npx -y @lettio/mcp. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
npm · @lettio/mcp
claude mcp add eu-lettio-mcp -- npx -y @lettio/mcp
{
"mcpServers": {
"eu-lettio-mcp": {
"command": "npx",
"args": [
"-y",
"@lettio/mcp"
]
}
}
} {
"servers": {
"eu-lettio-mcp": {
"command": "npx",
"args": [
"-y",
"@lettio/mcp"
]
}
}
} codex mcp add eu-lettio-mcp -- npx -y @lettio/mcp
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"eu-lettio-mcp": {
"type": "local",
"command": [
"npx",
"-y",
"@lettio/mcp"
],
"enabled": true
}
}
} openclaw mcp add eu-lettio-mcp --command npx --arg -y --arg @lettio/mcp
mcp_servers:
eu-lettio-mcp:
command: "npx"
args: ["-y", "@lettio/mcp"] {
"McpServers": {
"eu-lettio-mcp": {
"Transport": "stdio",
"Command": "npx",
"Arguments": [
"-y",
"@lettio/mcp"
]
}
}
} assistant mcp add eu-lettio-mcp -t stdio -c npx -a -y @lettio/mcp
{
"mcpServers": {
"eu-lettio-mcp": {
"command": "npx",
"args": [
"-y",
"@lettio/mcp"
]
}
}
} Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 25 Sept 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 24 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 27 to 30. That category is still filling its 30-day observation window: 8 days of observed history at the previous scan, 9 at this one. The score rises as the window fills, whether or not the server changes.
- 23 Sept 26 +3
- Stability: unverified → 0.27 ▲ functional
- 22 Sept 26 0
- Security disclosure: unverified → fail ▼ functional
- 21 Sept 26 0
- Security disclosure: fail → unverified ▼ functional
- 17 Sept 26 +15
- Malware scan: unverified → pass ▲ security
- 15 Sept 26 55
First indexed and scored.
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 25 Sept 2026 · Analysed npm/@lettio/mcp@0.1.2
Provenance No attestation
The registry publishes no build provenance for this version, so there is nothing to verify.
| Result | No attestation |
|---|---|
| Ecosystem | npm |
Background: How many MCP packages publish verified provenance →
Dependencies 96 packages
| Packages resolved | 96 |
|---|---|
| Stale | 31 |
| Tree resolution | Complete |
Background: SBOMs and build attestations, explained →
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
flag_email ~59
Flag (star) or unflag an email.
| Name | Type | Req | Description |
|---|---|---|---|
| account | string | – | Which configured account the email belongs to. |
| flagged | boolean | yes | true to flag/star, false to remove the flag. |
| id | string | yes | The email id. |
No output schema declared.
No examples provided.
list_accounts ~21
List the Lettio mailboxes this server is configured to access.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
list_mailboxes ~40
List the folders (mailboxes) in a Lettio account, with message and unread counts.
| Name | Type | Req | Description |
|---|---|---|---|
| account | string | – | Which configured account to use. |
No output schema declared.
No examples provided.
list_recent_emails ~84
List the most recent emails in a Lettio mailbox (defaults to the inbox).
| Name | Type | Req | Description |
|---|---|---|---|
| account | string | – | Which configured account to use. Omit to use the first. |
| limit | integer | – | How many messages (default 10). |
| mailbox | string | – | Mailbox role or name, e.g. "inbox", "sent". Default inbox. |
No output schema declared.
No examples provided.
move_email ~88
Move an email to another folder. Use "archive" to archive, "trash" to move to Trash (reversible), or a folder name.
| Name | Type | Req | Description |
|---|---|---|---|
| account | string | – | Which configured account the email belongs to. |
| id | string | yes | The email id. |
| mailbox | string | yes | Target folder: role like "archive", "trash", "inbox", or a folder name. |
No output schema declared.
No examples provided.
read_email ~50
Read the full content of one email by its id (get ids from list/search first).
| Name | Type | Req | Description |
|---|---|---|---|
| account | string | – | Which configured account the email belongs to. |
| id | string | yes | The email id. |
No output schema declared.
No examples provided.
reply_email ~87
Reply to an email, keeping it in the same conversation thread. Sends as the mailbox only.
| Name | Type | Req | Description |
|---|---|---|---|
| account | string | – | Which configured account the email belongs to. |
| body | string | yes | Plain-text reply body. |
| id | string | yes | The id of the email to reply to. |
| reply_all | boolean | – | Also reply to the other recipients (Cc them). Default false. |
No output schema declared.
No examples provided.
search_emails ~63
Search a Lettio mailbox by free-text query (matches sender, subject and body).
| Name | Type | Req | Description |
|---|---|---|---|
| account | string | – | Which configured account to use. |
| limit | integer | – | How many results (default 10). |
| query | string | yes | Text to search for. |
No output schema declared.
No examples provided.
send_email ~77
Send an email from a Lettio mailbox. Use deliberately — this really sends.
| Name | Type | Req | Description |
|---|---|---|---|
| account | string | – | Which configured account to send from. |
| body | string | yes | Plain-text body. |
| cc | array | – | Optional Cc recipients. |
| subject | string | yes | Subject line. |
| to | array | yes | Recipient email addresses. |
No output schema declared.
No examples provided.
set_read_status ~57
Mark an email as read or unread.
| Name | Type | Req | Description |
|---|---|---|---|
| account | string | – | Which configured account the email belongs to. |
| id | string | yes | The email id. |
| read | boolean | yes | true to mark read, false to mark unread. |
No output schema declared.
No examples provided.
What is the Lettio MCP server?
Lettio MCP is listed in the public MCP registry as eu.lettio/mcp. Private, EU-hosted email for AI agents over JMAP: read, search, reply, organize, send. This page covers its npm package (@lettio/mcp).
Is the Lettio MCP server safe to use?
Lettio MCP scores 74 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 25 September 2026. It declares no install or post-install scripts. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.
What tools does the Lettio MCP server expose?
Lettio MCP exposes 10 tools: list_accounts, list_recent_emails, search_emails, read_email, send_email, and 5 more. Their descriptions and schemas cost roughly 626 tokens of context every time the server is loaded.
Is the Lettio MCP server still maintained?
Lettio MCP is still listed as active in the MCP registry. We last reached this channel on 25 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.
What licence is the Lettio MCP server under?
Lettio MCP declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.