discovery

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, covering the safety profile. The description adds the scoping fact that it doesn't need tickers or countries, but it doesn't disclose other behavioral aspects like pagination behavior or response shaping beyond what's in the schema. With annotations provided, this meets a baseline but adds limited extra context.

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 concise: a short purpose statement followed by a list of 27 indicators. The list is necessary to inform the agent of valid choices and avoids excessive prose. It front-loads the core purpose and is structured clearly, though the indicator list could have been linked to the enum rather than 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?

For a tool with 21 parameters, the description is notably incomplete. It does not explain that parameters like price_lower, volume_higher, etc., are filters applied only to certain indicators, nor does it clarify which indicators accept which filters. The schema's placeholder descriptions ('Value for price_lower') add little. While an output schema exists, the description still fails to give the agent a coherent picture of how to combine the indicator with the other parameters. This is a significant gap given the complexity.

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 description coverage is 100% (though most are trivial 'Value for X'), so the baseline is 3. The description itself adds no parameter semantics beyond listing possible indicator values, which are already in the enum. The schema's indicator description (with the example and behavior of omission) is helpful, but it's not from the tool description. Thus, no added value from the description.

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 clearly states the tool provides 'market discovery tools' (lists, screeners, gainers/losers, etc.), and the 'No tickers or countries needed' hint distinguishes it from sibling tools dealing with specific instruments or metrics. It's specific enough about the resource category, though it covers a broad set of sub-functions via the 'indicator' parameter.

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 description explicitly says 'No tickers or countries needed', which tells agents when to use this tool (for market-wide discovery without specific instrument identifiers). It lists available indicators, giving a clear menu of use cases. However, it doesn't explicitly name alternative tools for scenarios with tickers or countries, so guidance is clear but not exhaustive.

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