reddit_get_subreddit

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

Annotations already provide readOnlyHint=true, and the description adds meaningful behavioral context: the 404 ambiguity between misspellings and banned subreddits, and what information the tool returns. This goes beyond the structured annotation without contradicting it.

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?

Two tightly written sentences with zero fluff. The core purpose is front-loaded, and the usage guidance follows naturally. Every sentence earns its place.

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 simple single-parameter read tool with readOnlyHint, the description covers what is returned and the key edge case (404 behavior). No output schema exists, but the description adequately summarizes the return content, making it complete enough for an agent to invoke correctly.

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?

The input schema already fully documents the parameter with pattern and example, achieving 100% schema description coverage. The description does not add parameter-specific meaning beyond what the schema provides, so baseline 3 is appropriate.

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 states a specific verb ('Get'), the resource ('subreddit'), and the exact data returned ('description, subscriber count and current active users'). It also distinguishes itself from siblings by positioning it as a pre-listing check, which differentiates it from reddit_list_posts and reddit_search.

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 gives a clear use case ('Useful before listing posts, to confirm the name is right and the community is the one you meant'). It does not explicitly name alternative tools, but the context makes it clear when to use this tool versus listing or searching.

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