Market Summary

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

No annotations are present, so the description carries the full burden. It discloses the output concept (daily breadth counts) and the temporal scope ('today'), but does not mention whether the operation is read-only, requires authentication, or has any latency or side effects. This is minimal behavioral disclosure.

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?

A single sentence with no filler, front-loading the core concept ('overall market breadth') and then defining it concretely. Every word earns its place.

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 zero-parameter tool with an output schema, the description covers the essential purpose and return concept. It is adequate, though without annotations it omits any caveats about data scope, update frequency, or interpretation of 'today' — but these are minor given the simplicity of the tool.

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 input schema is empty (0 parameters), so the baseline is 4. The description does not need to explain parameters because there are none, and it does not introduce any implicit parameter confusion.

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 uses a specific resource ('overall market breadth') and a clear metric (counts of shares rose/fell/flat). It is easily distinguished from siblings like get_stock, top_movers, and search_stock, which focus on individual stocks or rankings.

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 guidance or mention of alternative tools. The description implies usage through the phrase 'overall market breadth,' but it does not state when to choose this over top_movers or get_stock.

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