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

Annotations already cover safety (readOnlyHint, openWorld=false), so the description's real value is the data-quality disclosure: most_blocked_category is legal gambling-blocking not political, and China is under-counted (GFW=anomaly). These honest caveats materially change how an agent should interpret results and are not recoverable from annotations. It lacks detail on output shape, but no parameters and a snapshot scope limit that concern.

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?

The core purpose is front-loaded in the first clause, followed by a tight enumeration and then the honesty caveats. It is dense and runs long across two sentences, but nearly every clause carries information an agent needs; minimal waste.

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 no parameters and no output schema, the description carries the full burden and delivers by listing the return contents and qualifying their reliability. An agent has everything required to decide to call it, call it with no args, and interpret the response.

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 schema has zero parameters and 100% coverage, so there is nothing to document and the baseline for 0 params is 4. The description correctly adds no parameter noise.

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+resource ("One-call snapshot of the state of global censorship Voidly measures") and then enumerates exactly what the snapshot contains: countries measured, confirmed national blocks, deepest censor, broadest-blocked category, depth, coverage, freshness. This makes it immediately distinguishable from the many sibling per-metric endpoints (e.g. get_most_censored, get_national_blocklist).

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 ideal first call" plus the example query routes the agent to this as the entry point, and naming "links to the per-metric endpoints" signals the alternatives for drill-down. However, it never states an explicit when-not condition, so the selection guidance is strong but not complete.

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