reddit-mcp-server

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

Annotations already declare readOnlyHint=true and openWorldHint=true, and the description adds value by stating what is returned (titles, scores, comments) and detailing sort options and defaults. This provides behavioral context beyond the structured fields, though it doesn't disclose potential errors or limits.

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

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

The description is compact and front-loaded: one purpose sentence followed by a clear argument list. Every sentence is informative and there is no redundancy, making it easy for an agent to parse quickly.

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

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

With no output schema, the description explicitly states the return fields (titles, scores, comments) and documents all parameters. It does not cover error cases or rate limits, but for a simple read-only tool this is sufficient and complete enough for invocation.

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

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

Schema description coverage is 0%, so the description carries full responsibility for parameter meaning. It does this well: it gives an example for subreddit, lists valid sort values ('hot', 'new', 'top'), and specifies defaults for both sort and max_results, adding significant meaning beyond the raw schema.

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

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

The description clearly states the verb and resource: 'Get posts from a subreddit' and even lists the return fields (titles, scores, comments). While it does not explicitly differentiate from sibling tool search_reddit, the purpose is specific enough to be understood.

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

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

The use case is implied: fetching posts from a specific subreddit. However, there is no explicit when-to-use or when-not-to-use guidance, and no mention of the sibling search_reddit as an alternative, leaving the decision to the agent.

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

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is clear. The description adds useful behavioral context by specifying the return content (titles, scores, comments, content) and the default max_results. However, it does not disclose rate limits, sorting behavior, or potential limitations.

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

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

The description is concise, with a clear opening sentence and a structured parameter list. Every element provides value, and the format is easy to scan.

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

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

For a read-only search tool with 3 parameters, the description covers the essential inputs and outputs. It lacks details about result ordering or result count limits beyond the default, but these are not critical given the straightforward nature of the tool and the presence of an output-free schema.

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

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

Schema description coverage is 0%, so the description fully compensates by explaining each parameter with examples: query ('best programming language'), subreddit ('programming'), and max_results (default 20). This goes well beyond the bare schema definitions.

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

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

The description clearly states the tool's function: 'Search Reddit posts' and what it returns ('titles, scores, comments, and content'). This distinguishes it from the sibling tool 'get_subreddit', which presumably retrieves subreddit metadata rather than searching posts.

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

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

The description implies usage through the optional 'subreddit' parameter and provides concrete query examples, but it does not explicitly state when to use this tool versus the sibling 'get_subreddit' tool. There is no exclusion or alternative guidance.

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