yahoo_market_data

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

No annotations are provided, so the description must carry the full burden. It only says 'Get' which implies read-only, but does not explicitly state it is non-mutating, nor does it disclose response format, potential delays, or limitations. This is insufficient without annotations.

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 two sentences, front-loaded with the tool's purpose and a clear usage statement. Every word earns its place, with no redundancy or unnecessary detail.

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?

The description is somewhat incomplete: it doesn't specify what 'information' about indices is returned (e.g., current value, change) and no output schema exists to clarify. It also omits mention of the default indices, though that is in the schema. For a simple tool, it works but has clear gaps.

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 schema provides full coverage (100%) for the single optional parameter 'indices', including a clear description with examples. The tool description adds no extra parameter details beyond echoing 'major market indices', so baseline 3 is appropriate.

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 gets current market data from Yahoo Finance, specifically for major market indices. It distinguishes itself from siblings (stock quotes and history) by focusing on broad market overview and sentiment.

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 provides explicit usage context: 'Use this for broad market overview and current market sentiment.' This indicates when to use the tool, though it does not explicitly name alternative tools or state when not to use it.

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