Categories

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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so safety is covered. The description adds real behavioral content beyond them: counts are live, results are ordered biggest-first, and output shape varies by mode. It stops short of noting combination behavior (e.g. query plus category) or rate/latency characteristics.

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 tight sentences, front-loaded with the resource, then the mode-to-argument mapping. No filler, no repetition of the title or schema.

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 2-parameter read-only browser with a full output schema, the description covers all primary invocation paths and need not explain return fields. The only gap is the undefined interaction when query and category are supplied together, which an agent might reasonably attempt.

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 both parameters are already documented and the baseline would be 3. The description goes further by tying each parameter (or its absence) to a distinct result mode and stating the sort order for the query case, which is meaning the schema itself does not convey.

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 concrete resource (999.md category tree with live ad counts) and spells out three operating modes keyed to the arguments supplied. It is clearly distinct from search/ad-lookup siblings, though it never names an alternative tool, which keeps it short of the top mark.

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 explicit trigger conditions: no arguments for top-level categories, a category for its subcategories, a query to find where matching ads live. It does not say when NOT to use it or route the agent to search/get_filters instead, so it lacks the exclusion/alternative half of a 5.

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