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

Goes well beyond the readOnly/openWorld annotations by disclosing operational behavior: a 503 with Retry-After means throttling and should be retried after that delay, and native-source failures can fall back to Redlib with source.type and public fields/credit weights preserved. These are genuinely useful runtime traits not present in structured fields.

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?

Four sentences, front-loaded with the core purpose before operational details; each sentence earns its place. Slightly dense but not padded.

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?

An output schema exists, so return values need not be described, and the description covers the key runtime concerns (throttling, fallback, source labeling). Complete for an agent to call it correctly, with only minor sibling disambiguation missing.

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 100% (after, limit, subreddit all documented), so the schema already carries parameter meaning. The description's word 'flat' hints at structure but adds no syntax or format detail beyond the schema, matching the baseline 3.

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?

States a specific verb (Returns), resource (flat public comment entries) and scope (from a subreddit latest-comments feed), and explicitly names the sibling it is not (reddit_comments for post comments). An agent can distinguish it without opening the schema.

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?

Explicitly routes the agent to reddit_comments for post comments, giving a clear when-to-use alternative. It does not, however, distinguish itself from reddit_user_comments or reddit_subreddit_posts, leaving some sibling ambiguity.

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