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

With no annotations present, the description carries the full behavioral burden, and it does disclose genuinely non-obvious traits: pay-per-call at $0.005 USDC on Base, and that unpaid calls return a 402 challenge. However, it says nothing about what the required url parameter represents, whether results are cached or live, or whether the call is a safe read.

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 payload description is front-loaded, followed by provenance and payment terms in compact sentences. Nothing is padded, though the payment sentence packs several distinct facts (price, currency, chain, protocol, 402 behavior) into one dense clause.

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 output schema, the description does a reasonable job sketching return contents (totals, breakdowns, price bands, growth). But for a tool whose only input is an unexplained url and whose semantics differ from three similarly named siblings, the definition is not sufficient on its own to call it correctly.

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 nominally 100%, but the sole property description is the vacuous string 'required', which conveys no meaning. The description does not compensate at all - it never mentions what url should contain (endpoint? resource? filter?) for this single required parameter.

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 states a concrete resource and enumerates its contents: total paid resources indexed, breakdown by source/network, price bands, new endpoints in last 24h, daily growth. That is specific enough to tell it apart from census_search or census_price-changes in substance, though it never names those siblings explicitly. The one gap is that it never says what the tool actually does operationally with the required url argument.

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?

There is no statement of when to choose this over the three sibling census tools, even though the 'new endpoints in last 24h' content visibly overlaps census_new and the price-band content overlaps census_price-changes. The agent is left to infer routing from field lists alone.

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