Reddit MCP Server

get_subreddit_rules

Read-only

Retrieve a subreddit's posting rules: each rule's name, scope, and description. Use it before creating a post to check requirements and avoid automatic removal.

Instructions

Get a subreddit's posting rules (each rule's name, what it applies to, and its description). Read-only; works anonymously. Returns the rules list, or a note when the subreddit lists none. Call this before create_post to check requirements and avoid auto-removal. For available post flairs use get_post_flairs instead.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "subreddit_name": "<subreddit_name>"
    },
    "name": "get_subreddit_rules"
  }
}

Input Schema

Name	Required	Description	Default
`subreddit_name`	Yes	The subreddit name, without the r/ prefix (e.g. 'AskReddit').

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.5.3Aug 20, 2026

TDQS

A4.5/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, and the description reinforces 'Read-only' while adding 'works anonymously'. It also discloses the return behavior (rules list or a note when none exist) and the practical consequence of avoiding auto-removal, which goes beyond what annotations provide.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Four sentences, each earning its place: purpose, read-only/anonymous, return behavior, usage context, and alternative tool. It's front-loaded with the key action and free of filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple one-parameter tool with no output schema, the description is complete: it explains what the tool returns, when to use it, that it's read-only and anonymous, and how it relates to create_post and get_post_flairs. No gaps remain.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema fully describes the only parameter (subreddit_name, no r/ prefix, with example). Since schema coverage is 100%, the description doesn't need to add param-level detail; it stays at the tool-level purpose. Baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb 'Get' and the resource 'a subreddit's posting rules', and even breaks down what each rule includes (name, scope, description). It also distinguishes itself from sibling tools by explicitly pointing to get_post_flairs for flairs, making it unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives explicit when-to-use guidance: 'Call this before create_post to check requirements and avoid auto-removal.' It also names the alternative tool for flairs, providing a clear decision context versus siblings.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.