Is the xmark MCP server safe?

No scan can promise that. What its definitions show: 11 tools, 4 of which can change, send or delete something, and 0 findings from fixed checks. Allow the reads, ask before each change, and deny the deletes; the permissions block on this page does that.

Can the xmark MCP server delete data?

Yes. 2 tools can delete, cancel or revoke something: delete_bookmark and delete_conversation.

Can the xmark MCP server do things that cannot be undone?

No tool is classed as irreversible: none of them sends, pays, publishes or merges, going by their definitions.

What tools does the xmark MCP server have?

11 tools: 2 destructive, 2 write, 7 read. delete_bookmark, delete_conversation, sync_bookmarks, chat, list_bookmarks, get_bookmark, search_bookmarks, list_conversations and 3 more.

Does the xmark MCP server need sign-in or OAuth?

Its remote endpoint listed its tools to an anonymous client, without sign-in.

Does the xmark MCP server send data to outside services?

None of its tools sends, posts or publishes, or takes a recipient, channel or URL.

Has the xmark MCP server changed its tools?

Not since anlyon.dev started tracking it. Last scanned Nov 13, 2026.

xmark MCP server

io.github.JCLVSH/xmarkJCLVSHstreamable-httpv0.7.3Scanned 33 hours ago

Search and chat with your X bookmarks, with citations back to the original posts.

11 tools: 2 can delete or cancel things, 2 change things and 7 only read.

Reads private data · 4
Reads text others write · 3
Can send data out · 0
No findings

Tools listed without sign-in. Remote posture

With Anlyon

2 tools here can delete or cancel things. Govern them.

Anlyon lists the tools and adopts none.
Each tool you adopt gets approvals and receipts.
Your agent never holds the key.

Govern this server →

A tool your agent calls directly is not routed through Anlyon and is not governed by it. anlyon.dev only lists and labels, and these labels are the same either way.

What the xmark MCP server can do

The xmark MCP server is published by the GitHub account JCLVSH. It has 11 tools. It can delete or cancel things (2 tools: delete_bookmark and delete_conversation) and create or change data (2 tools: sync_bookmarks and chat). 7 tools only read.

4 tools read private data (list_conversations, get_conversation_messages, get_usage and 1 more); 3 tools bring in text other people can write (list_conversations, get_conversation_messages and get_usage).

None of the fixed checks matched anything in its tool definitions. That is not a safety guarantee.

Its remote endpoint lists its tools without sign-in.

Last scanned Nov 13, 2026, version 0.7.3.

Tools

Grouped by what each tool does, most consequential first. Open one for its reasons and full description; descriptions are the publisher's own words.

11 tools

Deletes or cancels 2Removes, cancels or revokes something.Claude Code: deny

delete_bookmarkRemove a bookmark.No findings
Why it is in this group
- The name "delete_bookmark" says "delete": a word for removing or ending something.
- The server marks it destructive (destructiveHint: true).
Description, as the server wrote it
Remove a bookmark. Local-only by default — the next sync re-creates anything still bookmarked on X. Set unbookmark=true to also remove it on X (sticks across syncs; requires a connected X account).
Annotations the server declares
- readOnlyHint: false
- destructiveHint: true
delete_conversationPermanently delete a conversation and its messages.No findings
Why it is in this group
- The name "delete_conversation" says "delete": a word for removing or ending something.
- The description says "Permanently delete".
- The server marks it destructive (destructiveHint: true).
Description, as the server wrote it
Permanently delete a conversation and its messages. Free tier allows one concurrent conversation, so deleting is how a free account starts a fresh chat.
Annotations the server declares
- readOnlyHint: false
- destructiveHint: true

Changes things 2Creates or changes something that can be changed back.Claude Code: ask

chatAsk a natural-language question about the user's X bookmarks.No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
Description, as the server wrote it
Ask a natural-language question about the user's X bookmarks. Returns an answer with citations back to the original tweets. Free tier includes 20 chat messages per month.
Annotations the server declares
- readOnlyHint: false
- destructiveHint: false
sync_bookmarksTrigger a fresh sync from X.No findings
Why it is in this group
- The name "sync_bookmarks" says "sync": a word for a change.
Description, as the server wrote it
Trigger a fresh sync from X. Pulls latest bookmarks, embeds new ones for semantic search. Free tier allows one sync per day.
Annotations the server declares
- readOnlyHint: false
- destructiveHint: false

Only reads 7Looks things up and changes nothing.Show 7 read-only tools

get_bookmarkFetch a single bookmark by ID.No findings
Why it is in this group
- The name "get_bookmark" says "get": a word for reading.
Description, as the server wrote it
Fetch a single bookmark by ID.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
get_changelogmachine-readable release history (public) - version, date, type, summary, migration notes on breaking entries.Reads private dataNo findings
Why it is in this group
- The name "get_changelog" says "get": a word for reading.
What it can reach
- private-dataThe description's first sentence says "note": it reads notes.
Description, as the server wrote it
machine-readable release history (public) - version, date, type, summary, migration notes on breaking entries. the X-Notice header's structured backstory.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
get_conversation_messagesA conversation's message history, oldest first.Reads private dataReads text others writeNo findings
Why it is in this group
- The name "get_conversation_messages" says "get": a word for reading.
What it can reach
- private-dataThe name "get_conversation_messages" says "get" and "conversation": it reads messages.
- private-dataThe description's first sentence says "conversation": it reads messages.
- untrusted-inputThe name "get_conversation_messages" says "get" and "conversation": it reads messages, which other people can write.
- untrusted-inputThe description's first sentence says "conversation": it reads messages, which other people can write.
Description, as the server wrote it
A conversation's message history, oldest first. Assistant messages carry the IDs of the bookmarks retrieved for that answer.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
get_usageThe authenticated user's plan and quota usage: chat messages this month, syncs today, bookmark count, and whether an X account is connected.Reads private dataReads text others writeNo findings
Why it is in this group
- The name "get_usage" says "get": a word for reading.
What it can reach
- private-dataThe description's first sentence says "chat": it reads messages.
- untrusted-inputThe description's first sentence says "chat": it reads messages, which other people can write.
Description, as the server wrote it
The authenticated user's plan and quota usage: chat messages this month, syncs today, bookmark count, and whether an X account is connected. Limits are null on unlimited plans.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
list_bookmarksList the authenticated user's X bookmarks.No findings
Why it is in this group
- The name "list_bookmarks" says "list": a word for reading.
Description, as the server wrote it
List the authenticated user's X bookmarks. Paginated.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
list_conversationsList the user's past chat conversations.Reads private dataReads text others writeNo findings
Why it is in this group
- The name "list_conversations" says "list": a word for reading.
What it can reach
- private-dataThe name "list_conversations" says "list" and "conversation": it reads messages.
- private-dataThe description's first sentence says "list" and "chat": it reads messages.
- untrusted-inputThe name "list_conversations" says "list" and "conversation": it reads messages, which other people can write.
- untrusted-inputThe description's first sentence says "list" and "chat": it reads messages, which other people can write.
Description, as the server wrote it
List the user's past chat conversations. Paginated.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false
search_bookmarksSemantic search over the user's bookmarks.No findings
Why it is in this group
- The name "search_bookmarks" says "search": a word for reading.
Description, as the server wrote it
Semantic search over the user's bookmarks. Returns ranked matches with relevance scores.
Annotations the server declares
- readOnlyHint: true
- destructiveHint: false

This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.

Exfil surface

Which tools read private data, which read text someone else can write, and which can send data out. One of each is a path a prompt injection can use.

No private-data, untrusted-input, outbound path in this server alone: no tool is tagged outbound.

Reads private data4: Reads files, mail, messages, databases, secrets, calendars or repositories.; get_changelog
get_conversation_messages
get_usage
list_conversations
Reads text others write3: Brings in text someone else can write: web pages, inbound email, messages, issues and comments.; get_conversation_messages
get_usage
list_conversations
Can send data out0: Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL.

Other servers in the same agent add their own tools to these paths. Audit your whole setup to see them together.

Remote posture

What anyone on the internet sees at the remote endpoint: an anonymous initialize and tools/list, and the public OAuth metadata.

Tools listed without sign-in

Looked at Nov 10, 2026, 08:19 UTC, unchanged since Nov 10, 2026. No credentials were sent and no tool was called. What is looked at.

Reachable: yes
HTTP status of an anonymous initialize: 200
tools/list served without credentials: yes
Tools that change things, listed without credentials: 4
Protocol version: 2025-06-18
WWW-Authenticate on 401: not observed
resource_metadata in WWW-Authenticate: not observed
RFC 9728 protected resource metadata: not observed
Authorization servers: not observed
Legacy HTTP+SSE transport: no
Dynamic client registration: not observed
Client ID metadata documents: not observed

HighThe whole server
The endpoint served tools/list without credentials, and the list has 4 tools that change things (2 destructive, 2 write). Whether a call also works without credentials was not tested: tools are never called.
Matched text
https://api.xmark.dev/mcp: tools/list returned 11 tools to an anonymous client, including delete_bookmark (destructive), delete_conversation (destructive), sync_bookmarks (write), chat (write)
What this check looks for

Findings

Matches of fixed checks, with the text they matched.

No check matched anything in these tool definitions. That is not a safety guarantee.

History

Changes to its tool definitions and to its remote endpoint, newest first.

No change seen yet. Its tools are rescanned every day, and a remote endpoint is looked at once a week.

All changes to this server

Install

Pinned to version 0.7.3. Values in angle brackets are yours to fill in.

claude mcp add --transport http xmark https://api.xmark.dev/mcp --header 'Authorization: <your-authorization>'

claude mcp add --transport http xmark https://api.xmark.dev/mcp --header 'Authorization: <your-authorization>'

Run in a terminal.

Claude Code permissions

Allow the reads, ask before a change or a way out, deny the deletes. Paste into .claude/settings.json.

.claude/settings.json

{
  "permissions": {
    "allow": [
      "mcp__xmark__list_bookmarks",
      "mcp__xmark__get_bookmark",
      "mcp__xmark__search_bookmarks",
      "mcp__xmark__list_conversations",
      "mcp__xmark__get_conversation_messages",
      "mcp__xmark__get_usage",
      "mcp__xmark__get_changelog"
    ],
    "ask": [
      "mcp__xmark__sync_bookmarks",
      "mcp__xmark__chat"
    ],
    "deny": [
      "mcp__xmark__delete_bookmark",
      "mcp__xmark__delete_conversation"
    ]
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. A read that can send data out (it takes a URL, say) asks first too. It assumes the server is installed as xmark. Review it before you use it.

Capability tags behind 4 rules

mcp__xmark__list_conversations private-data, untrusted-input
mcp__xmark__get_conversation_messages private-data, untrusted-input
mcp__xmark__get_usage private-data, untrusted-input
mcp__xmark__get_changelog private-data

Keep the decision: fail CI when the tools change, follow every change, or show a badge.

Pin in CI

Fail a build when the tools you reviewed are not the tools the server serves today.

curl -s "https://anlyon.dev/api/v1/servers/io.github.JCLVSH/xmark/verify?hash=e6189f759ccb8c0b81c2ae6242f30ef9d06c4b94920e05f036479c045e185173" | jq -e '.changed == false'

Pinned hash e6189f759ccb, from Nov 13, 2026, 17:18 UTC.

Watch

Get told when its tools change: a new tool, a new description, a new class.

https://anlyon.dev/servers/io.github.JCLVSH/xmark/changes.xml

An Atom feed. Works in any feed reader or Slack's RSS app.

Badge

[![anlyon.dev](https://anlyon.dev/badge/io.github.JCLVSH/xmark.svg)](https://anlyon.dev/servers/io.github.JCLVSH/xmark)

Source: MCP Registry. Synced Nov 13, 2026, 17:18 UTC.

xmark MCP server: questions and answers

Answered from the scan above, not from the publisher's description.

Is the xmark MCP server safe?: No scan can promise that. What its definitions show: 11 tools, 4 of which can change, send or delete something, and 0 findings from fixed checks. Allow the reads, ask before each change, and deny the deletes; the permissions block on this page does that.
Can the xmark MCP server delete data?: Yes. 2 tools can delete, cancel or revoke something: delete_bookmark and delete_conversation.
Can the xmark MCP server do things that cannot be undone?: No tool is classed as irreversible: none of them sends, pays, publishes or merges, going by their definitions.
What tools does the xmark MCP server have?: 11 tools: 2 destructive, 2 write, 7 read. delete_bookmark, delete_conversation, sync_bookmarks, chat, list_bookmarks, get_bookmark, search_bookmarks, list_conversations and 3 more.
Does the xmark MCP server need sign-in or OAuth?: Its remote endpoint listed its tools to an anonymous client, without sign-in.
Does the xmark MCP server send data to outside services?: None of its tools sends, posts or publishes, or takes a recipient, channel or URL.
Has the xmark MCP server changed its tools?: Not since anlyon.dev started tracking it. Last scanned Nov 13, 2026.