Is the CommunityMentions connector free?

Yes. It needs no account, no API key and no card. CommunityMentions sells a done-for-you service, but the data tools cost nothing to use.

Does Claude need permission to post on Reddit?

No, because the connector can't post. Both tools are read-only and only return subreddit data.

Which Claude plans can add it?

Anthropic says custom connectors work on Free, Pro, Max, Ultra, Team and Enterprise plans, with Free limited to one (read November 6, 2026). On Team and Enterprise an Owner adds it first.

Why does Claude return different picks for the same prompt?

The tools return the same data, but the model decides how to use it. In our test Claude also looked up subreddit details to fill in its answer. Ask for the ranking you want in the prompt.

Connect Claude to CommunityMentions: MCP Setup Steps (2026)

Quick picks: what are you using?

Claude Code: run the one command below.
Claude on the web or Claude Desktop: add a custom connector with the URL below (these are Anthropic's steps; we did not run them).
A Team or Enterprise plan: an Owner adds the connector first, by Anthropic's rule.
Your own client, or you want the raw JSON: read the MCP server reference.
You only need one answer: the subreddit finder gives it with no setup.

Connect Claude Code

Run this in the project where you want the tools:

claude mcp add --transport http communitymentions https://communitymentions.com/api/mcp
claude mcp list

What done looks like in Claude Code

The list command prints the server with a Connected status. This is the line we got on November 6, 2026, on Claude Code 2.1.318:

communitymentions: https://communitymentions.com/api/mcp (HTTP) - ✔ Connected

Connect Claude on the web or Desktop

Add the URL as a custom connector with No sign in. These steps are Anthropic's, for an individual Pro or Max plan, read from its help center on November 6, 2026. Free plans can add one custom connector. On Team and Enterprise, an Owner (or, on Enterprise, someone with a custom role that includes Manage access to Libraries) first adds it under Organization settings > Connectors > Add > Custom > Web with the same URL, and members then connect it under Customize > Connectors. We ran the Claude Code steps above and did not click through any of these in a signed-in account.

Go to Customize > Connectors.
Click + Add, then Add custom connector.
Name it CommunityMentions.
Paste https://communitymentions.com/api/mcp and click Continue.
Under Authentication, choose No sign in, then click Add.
In a chat, open the + button, then Connectors, and turn CommunityMentions on.

A real prompt and what Claude said

We asked this in Claude Code on November 6, 2026, with Claude Haiku 5.5 and only the CommunityMentions server connected:

> Using the CommunityMentions tools, which subreddits fit a project management tool for small agencies? Name the top 3 with their AI citation counts.

Ranked by closest match, the top 3 are:

1. **r/smallbusiness**: 210 AI citations (204 answers citing it, 77 threads cited)
2. **r/smallbusinessowner**: no aggregate citation count. The tool returned null, which means no data, not zero. Its most-cited threads have 1 citation each.
3. **r/AiForSmallBusiness**: no aggregate citation count (null). Its most-cited thread, "How to create employee training videos," has 6 citations.

r/smallbusiness is the only one of the three with a reported total. If you rank strictly by citations across all matches, r/AI_Agents (117) is the next highest, followed by r/generativeAI (68) and r/automation (62). Most of those fit less well as a project management audience, though r/AI_Agents may be worth a look.

Why some counts come back empty

A subreddit with fewer than 50 AI citations comes back with no count, because we don't publish counts under 50. That's why Claude said null for two of its three picks above. It means under 50, and the subreddit can still be a good fit. To rank by citations instead of fit, ask for that in your prompt. Of the 211 subreddits in the data, 105 carry a published citation count.

What Claude can't do with it

Post, comment or change anything. Both tools only read.
See your account, your comments or any client's data. The tools take no login.
Tell you what Claude itself cites. The data covers OpenAI models, Perplexity and Gemini.
Quote our prices. The tools carry subreddit data only; prices are on our pricing section.
Look at health, legal-help or adult communities, which are left out.
Return live numbers. Each find_subreddits result carries the date of its data, and the current data is dated November 1, 2026.

Errors we hit while testing

If you call the endpoint by hand rather than through Claude, these are the ones we ran into on November 6, 2026. A curl call without the JSON content type header got 415 Unsupported Media Type, and one without an Accept header naming both application/json and text/event-stream got 406 Not Acceptable. A call that sent query where the tool wants description got a -32602 input validation error. Opening the URL in a browser sends a GET, which answers 405; that's normal, because the server only takes POST. The server reference has working calls.

Sources

Anthropic: get started with custom connectors using remote MCP, read November 6, 2026.
Official MCP registry entry, read November 6, 2026.
The live endpoint, called from Claude Code 2.1.318 on November 6, 2026. Totals come from its initialize response, on data dated November 1, 2026.

Connect Claude to CommunityMentions