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

Annotations cover the safety profile (readOnly, openWorld, idempotent, non-destructive), yet the description adds material behavior the schema cannot: $0.03 per call via x402/USDC on Base, no charge for refusals/errors/under-30 decided posts, and returns of links only with no text or usernames. This is well beyond the annotation baseline.

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?

Front-loads the identity ('Online discourse sample, NOT a poll') then packs pricing and constraints into one dense block with no filler sentences. It reads as a run-on in places, but every clause carries information.

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?

No output schema exists, so the description compensates by sketching the return shape (per-side share with 95% interval and n, counts per source, links, caveats). Combined with the refusal and billing rules, an agent has everything needed to call and interpret it.

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 coverage is 100%, so q, sides and window are already fully documented in the schema with the same ranges, defaults and refusal notes. The description largely restates them (q required, sides 2-4, window 1-30d), adding little new semantic detail, so the baseline 3 applies.

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 and resource ('see how public Hacker News and Bluesky posts split on a question') and explicitly disclaims being a poll. The named sources and the split-per-side output make it unmistakable against any sibling, none of which do sentiment/discourse aggregation.

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?

Gives clear when-to-use ('use to see how public Hacker News and Bluesky posts split on a question') plus hard exclusions (elections, health, a named person's conduct). It does not point to an alternative sibling for questions outside scope, which keeps it short of a 5.

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