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

With no annotations, the description carries the full behavioral burden but only partially meets it. It discloses the active-deals filter and that counts are included, but it does not say whether the operation is read-only, what the counts represent, or how results are ordered or returned.

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 description is a single front-loaded phrase with no filler, and every element earns its place. It is slightly under-specified rather than over-long, and the slash construction 'Countries/markets' is mildly ambiguous.

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?

Given zero parameters and no output schema, the description gives the core scope and mentions counts but leaves return-shape details unexplained. It is adequate for an agent to understand the general output, but not complete enough to know exactly what each count represents or how the result set is structured.

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 tool takes zero parameters, so parameter semantics are not applicable and the baseline is 4. The description does not need to explain any input parameters.

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 the resource (countries/markets) and a specific scope (currently have active deals) plus an output trait (with counts), which distinguishes it from sibling list tools like list_brands or list_hot_deals. It is clear but not framed as a full verb-resource statement, and it does not explicitly contrast with close alternatives such as get_market_overview.

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 explicit when-to-use or when-not-to-use guidance. The description implies the tool is for finding markets that have active deals, but it does not name the alternative tools or the conditions under which an agent should choose this over search_deals or get_market_overview.

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