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

Beyond readOnlyHint/openWorldHint it discloses exact-phrase matching semantics, per-network coverage caveats, that results never include the author, the full result field set, gating on paid plans with an upgrade-link response on Free, and precise credit pricing including the worked example for the default configuration. This is the kind of cost and coverage disclosure an agent needs before spending credits.

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?

One dense paragraph with no wasted sentences and the differentiation front-loaded; every clause carries factual weight (networks, fields, pricing). It would scan better as short labeled lines given the number of facts, but the content is 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?

For a 7-parameter, no-output-schema, multi-network search tool, the description covers purpose, alternatives, per-network limits, return fields, author exclusion, plan gating, and cost model — everything needed to invoke it correctly and predict the response shape.

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% with inline enum descriptions, so baseline is 3; the description adds meaning the schema does not — that the default platform set is Reddit only, that 'comments' means replies on X, and that limit drives per-page credit cost (default costs 10–25). It stops short of mapping each parameter individually, hence 4 rather than 5.

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 — monitors mentions of a brand/competitor/product/topic — and immediately contrasts with the named sibling search_viral_content (trending, sorted by reach) versus exact-phrase matching here. An agent can pick between the two without opening either 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 names the alternative and the condition that selects it ('unlike search_viral_content, which finds what is trending and sorts by reach'). It also specifies which networks support what (YouTube comments unsearchable, LinkedIn returns under errors at no cost) and the paid-plan prerequisite, so the agent knows when the call will and won't yield data.

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