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

Annotations already cover the safety profile (readOnlyHint, destructiveHint=false, openWorldHint=false), so the bar is lower. The description adds genuinely valuable epistemic context the annotations cannot: "invisible" means zero pickup in Horizon-tracked Western feeds, not a claim about all media. That is a meaningful caveat about how results should be interpreted, though it says nothing about how counts are ranked or how far back the corpus reliably goes.

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?

Three sentences, each doing distinct work: definition first, decision-framing question second, methodological caveat last. The core definition is front-loaded and nothing is repeated.

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 an output schema present, return shape needn't be described, and annotations cover safety. Between them, the description, schema and output schema give the agent enough to decide when to call it, what the numbers mean, and the limits of the claim.

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% and both parameters (days, limit) carry defaults and ranges in the schema itself, so the description needs to add little. It adds nothing about parameter semantics — no hint about how widening days affects blind-spot detection or why limit caps at 50. 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?

The description defines the resource with unusual precision: companies, models and people covered by Chinese/East-Asian, European and Latin-American press but absent from Western/global feeds, ranked with per-region item counts. That is far more than a restatement of the name. It stops short of a 5 because it never contrasts itself with the overlapping siblings get_region_signal / get_china_signal, leaving the agent to infer that this is the cross-region gap view rather than a single-region view.

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 framing question "what is Western tech media missing right now?" gives a concrete trigger for selecting this tool, which is clear usage context. It offers no exclusions or named alternatives, so an agent weighing this against get_region_signal or search_news gets no explicit routing rule.

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