Can the Reddit Subreddit Posts, Search & Comments API 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.

Does the Reddit Subreddit Posts, Search & Comments API MCP Server send data to outside services?

6 tools can carry data out (it sends, posts or publishes, or takes a recipient, channel or URL): reddit_subreddit_posts, reddit_posts_search, reddit_post_detail, reddit_post_comments, reddit_popular_posts and reddit_user_posts.

Reddit Subreddit Posts, Search & Comments API MCP Server

io.redditdataapi/mcp-serverredditdataapi.iostreamable-httpv1.0.1Scanned 4 hours ago

Real-time Reddit posts, subreddit search, comments & brand mentions MCP. OAuth or API key.

9 tools: 7 change things and 2 only read.

Reads private data · 0
Reads text others write · 9
Can send data out · 6
7 findings

With Anlyon

7 tools here change 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 Reddit Subreddit Posts, Search & Comments API MCP Server can do

The Reddit Subreddit Posts, Search & Comments API MCP Server is published by redditdataapi.io, a domain the MCP Registry verified. It has 9 tools. It can create or change data (7 tools: reddit_subreddit_posts, reddit_posts_search, reddit_post_detail, reddit_post_comments and 3 more), but cannot delete data. 2 tools only read.

9 tools bring in text other people can write (reddit_subreddit_posts, reddit_subreddit_info, reddit_posts_search and 6 more); 6 tools can send data out of your system (reddit_subreddit_posts, reddit_posts_search, reddit_post_detail and 3 more).

The fixed checks matched 7 findings (annotation-conflict). Each one comes with the text it matched.

Last scanned Nov 5, 2026, version 1.0.1.

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.

9 tools

Changes things 7Creates or changes something that can be changed back.Claude Code: ask

reddit_popular_postsFetch front-page trending posts from r/popular across all of Reddit.Reads text others writeCan send data out1 finding
Why it is in this group
- The name "reddit_popular_posts" says "post": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
What it can reach
- untrusted-inputThe server marks it openWorldHint: true: it reaches things outside the server's own data.
- outboundThe name "reddit_popular_posts" says "post": it sends or publishes something to other people.
Findings
- Warn
  The server marks "reddit_popular_posts" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_popular_posts" says "post": a word for a change.
  What this check looks for
Description, as the server wrote it
Fetch front-page trending posts from r/popular across all of Reddit. Cost: 1 Credit ($0.0001) per returned post.
Annotations the server declares
- title: Get Trending r/popular Posts
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: true
reddit_post_commentsExtract up to 200 flattened nested comments per call with integer depth, parent_id, author, and upvote score (no recursive MoreComments calls needed).Reads text others writeCan send data out1 finding
Why it is in this group
- The name "reddit_post_comments" says "post": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
What it can reach
- untrusted-inputThe server marks it openWorldHint: true: it reaches things outside the server's own data.
- outboundThe name "reddit_post_comments" says "post": it sends or publishes something to other people.
Findings
- Warn
  The server marks "reddit_post_comments" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_post_comments" says "post": a word for a change.
  What this check looks for
Description, as the server wrote it
Extract up to 200 flattened nested comments per call with integer depth, parent_id, author, and upvote score (no recursive MoreComments calls needed). Cost: 1 Credit ($0.0001) per returned comment.
Annotations the server declares
- title: Get Nested Post Comment Tree
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: true
reddit_post_detailFetch full metadata, selftext body, upvote_ratio, score, and comment count for a single Reddit post by post_id or URL.Reads text others writeCan send data out1 finding
Why it is in this group
- The name "reddit_post_detail" says "post": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
What it can reach
- untrusted-inputThe server marks it openWorldHint: true: it reaches things outside the server's own data.
- outboundThe name "reddit_post_detail" says "post": it sends or publishes something to other people.
Findings
- Warn
  The server marks "reddit_post_detail" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_post_detail" says "post": a word for a change.
  What this check looks for
Description, as the server wrote it
Fetch full metadata, selftext body, upvote_ratio, score, and comment count for a single Reddit post by post_id or URL. Cost: 2 Credits ($0.0002).
Annotations the server declares
- title: Get Reddit Post Detail
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: true
reddit_posts_searchSearch Reddit posts globally or within a subreddit using boolean keywords/brand mentions and optional ?since= Unix timestamp polling.Reads text others writeCan send data out1 finding
Why it is in this group
- The name "reddit_posts_search" says "post": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
What it can reach
- untrusted-inputThe server marks it openWorldHint: true: it reaches things outside the server's own data.
- outboundThe name "reddit_posts_search" says "post": it sends or publishes something to other people.
Findings
- Warn
  The server marks "reddit_posts_search" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_posts_search" says "post": a word for a change.
  What this check looks for
Description, as the server wrote it
Search Reddit posts globally or within a subreddit using boolean keywords/brand mentions and optional ?since= Unix timestamp polling. Charges 0 Credits when 0 posts match! Cost: 1 Credit ($0.0001) per matched post.
Annotations the server declares
- title: Search Reddit Posts & Brand Mentions
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: true
reddit_subreddit_postsFetch real-time posts from any public Reddit subreddit (hot, new, top, rising) without Reddit OAuth 100 QPM limits.Reads text others writeCan send data out1 finding
Why it is in this group
- The name "reddit_subreddit_posts" says "post": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
What it can reach
- untrusted-inputThe server marks it openWorldHint: true: it reaches things outside the server's own data.
- outboundThe name "reddit_subreddit_posts" says "post": it sends or publishes something to other people.
Findings
- Warn
  The server marks "reddit_subreddit_posts" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_subreddit_posts" says "post": a word for a change.
  What this check looks for
Description, as the server wrote it
Fetch real-time posts from any public Reddit subreddit (hot, new, top, rising) without Reddit OAuth 100 QPM limits. Cost: 1 Credit ($0.0001) per returned post (min 2 Credits; 0 Credits on error/empty).
Annotations the server declares
- title: Get Subreddit Posts Feed
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: true
reddit_user_commentsFetch public comments posted by a specific Reddit username.Reads text others write1 finding
Why it is in this group
- The name "reddit_user_comments" says "comment": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
What it can reach
- untrusted-inputThe server marks it openWorldHint: true: it reaches things outside the server's own data.
Findings
- Warn
  The server marks "reddit_user_comments" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_user_comments" says "comment": a word for a change.
  What this check looks for
Description, as the server wrote it
Fetch public comments posted by a specific Reddit username. Cost: 1 Credit ($0.0001) per returned comment.
Annotations the server declares
- title: Get User Comment History
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: true
reddit_user_postsFetch public posts submitted by a specific Reddit username.Reads text others writeCan send data out1 finding
Why it is in this group
- The name "reddit_user_posts" says "post": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
What it can reach
- untrusted-inputThe server marks it openWorldHint: true: it reaches things outside the server's own data.
- outboundThe name "reddit_user_posts" says "post": it sends or publishes something to other people.
Findings
- Warn
  The server marks "reddit_user_posts" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_user_posts" says "post": a word for a change.
  What this check looks for
Description, as the server wrote it
Fetch public posts submitted by a specific Reddit username. Cost: 1 Credit ($0.0001) per returned post.
Annotations the server declares
- title: Get User Submitted Posts
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: true

Only reads 2Looks things up and changes nothing.Show 2 read-only tools

reddit_subreddit_infoGet subreddit metadata, subscriber count, active online users, creation date, and community description.Reads text others writeNo findings
Why it is in this group
- The description's first verb is "get": a word for reading.
What it can reach
- untrusted-inputThe server marks it openWorldHint: true: it reaches things outside the server's own data.
Description, as the server wrote it
Get subreddit metadata, subscriber count, active online users, creation date, and community description. Cost: 2 Credits ($0.0002) per lookup.
Annotations the server declares
- title: Get Subreddit Metadata & Subscribers
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: true
reddit_user_profileFetch public Reddit user profile metadata, link/comment karma, account age, and verification status.Reads text others writeNo findings
Why it is in this group
- The description's first verb is "fetch": a word for reading.
What it can reach
- untrusted-inputThe server marks it openWorldHint: true: it reaches things outside the server's own data.
- untrusted-inputThe description's first sentence says "fetch" and "comment": it reads comments, which other people can write.
Description, as the server wrote it
Fetch public Reddit user profile metadata, link/comment karma, account age, and verification status. Cost: 2 Credits ($0.0002).
Annotations the server declares
- title: Get Reddit User Profile & Karma
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: true

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 private-data.

Reads private data0: Reads files, mail, messages, databases, secrets, calendars or repositories.
Reads text others write9: Brings in text someone else can write: web pages, inbound email, messages, issues and comments.; reddit_popular_posts
reddit_post_comments
reddit_post_detail
reddit_posts_search
reddit_subreddit_info
reddit_subreddit_posts
reddit_user_comments
reddit_user_posts
reddit_user_profile
Can send data out6: Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL.; reddit_popular_posts
reddit_post_comments
reddit_post_detail
reddit_posts_search
reddit_subreddit_posts
reddit_user_posts

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

Findings

Matches of fixed checks, with the text they matched.

7 warn

Warnreddit_subreddit_posts
The server marks "reddit_subreddit_posts" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_subreddit_posts" says "post": a word for a change.
What this check looks for
Warnreddit_posts_search
The server marks "reddit_posts_search" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_posts_search" says "post": a word for a change.
What this check looks for
Warnreddit_post_detail
The server marks "reddit_post_detail" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_post_detail" says "post": a word for a change.
What this check looks for
Warnreddit_post_comments
The server marks "reddit_post_comments" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_post_comments" says "post": a word for a change.
What this check looks for
Warnreddit_popular_posts
The server marks "reddit_popular_posts" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_popular_posts" says "post": a word for a change.
What this check looks for
Warnreddit_user_posts
The server marks "reddit_user_posts" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_user_posts" says "post": a word for a change.
What this check looks for

Show 1 more finding

Warnreddit_user_comments
The server marks "reddit_user_comments" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "reddit_user_comments" says "comment": a word for a change.
What this check looks for

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 1.0.1. Values in angle brackets are yours to fill in.

claude mcp add --transport http redditdataapi https://api.redditdataapi.io/mcp

claude mcp add --transport http redditdataapi https://api.redditdataapi.io/mcp

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__redditdataapi__reddit_subreddit_info",
      "mcp__redditdataapi__reddit_user_profile"
    ],
    "ask": [
      "mcp__redditdataapi__reddit_subreddit_posts",
      "mcp__redditdataapi__reddit_posts_search",
      "mcp__redditdataapi__reddit_post_detail",
      "mcp__redditdataapi__reddit_post_comments",
      "mcp__redditdataapi__reddit_popular_posts",
      "mcp__redditdataapi__reddit_user_posts",
      "mcp__redditdataapi__reddit_user_comments"
    ],
    "deny": []
  }
}

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 redditdataapi. Review it before you use it.

Capability tags behind 9 rules

mcp__redditdataapi__reddit_subreddit_posts untrusted-input, outbound
mcp__redditdataapi__reddit_subreddit_info untrusted-input
mcp__redditdataapi__reddit_posts_search untrusted-input, outbound
mcp__redditdataapi__reddit_post_detail untrusted-input, outbound
mcp__redditdataapi__reddit_post_comments untrusted-input, outbound
mcp__redditdataapi__reddit_popular_posts untrusted-input, outbound
mcp__redditdataapi__reddit_user_profile untrusted-input
mcp__redditdataapi__reddit_user_posts untrusted-input, outbound
mcp__redditdataapi__reddit_user_comments untrusted-input

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.redditdataapi/mcp-server/verify?hash=f7eb2e3170e85d77cfdf5e4327726e90d4cfcbe2dd3695ca15c130abc043fbfe" | jq -e '.changed == false'

Pinned hash f7eb2e3170e8, from Nov 5, 2026, 15:18 UTC.

Watch

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

https://anlyon.dev/servers/io.redditdataapi/mcp-server/changes.xml

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Badge

[![anlyon.dev](https://anlyon.dev/badge/io.redditdataapi/mcp-server.svg)](https://anlyon.dev/servers/io.redditdataapi/mcp-server)

Source: MCP Registry. Synced Nov 5, 2026, 15:18 UTC.