top_losers

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

Annotations already declare readOnlyHint, openWorldHint, and destructiveHint, so the safety profile is covered. The description adds a clear success return type and a structured error envelope on any failure, which is useful and goes beyond the annotations. It does not contradict any annotation.

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 short sentences are front-loaded with the core purpose, followed by supported markets and the return/error contract. There is no filler or redundancy.

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 all parameters are optional with defaults and an output schema exists, the description covers the main selection logic and failure behavior. The remaining gap is the lack of enumerated timeframe values, which could cause an agent to pass an unsupported string, but overall the tool is callable from the description.

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?

With 0% schema description coverage, the description must carry parameter meaning. It adds concrete exchange choices and distinguishes crypto vs stock markets, but it still omits valid timeframe values and the meaning/range of limit. This is meaningful but incomplete compensation.

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 opens with a specific verb-resource pair, 'Return top losers for an exchange and timeframe,' which immediately distinguishes the tool from screening, price, and news tools. It also enumerates supported markets, so the agent knows its exact scope. This exceeds baseline clarity.

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 supported exchange list gives implicit guidance about where the tool applies, but there is no explicit 'use this instead of X' statement or exclusions. An agent must infer when to choose top_losers over top_gainers, futures_top_movers, or stock_screener. That is adequate but not strongly guided.

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