market_snapshot

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

No annotations are provided, so the description carries the responsibility for behavioral disclosure. It mentions 'Powered by Yahoo Finance' and lists data categories, which adds some transparency about source and coverage, but it does not disclose latency, update frequency, or return behavior.

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 and well-structured, with the first sentence front-loading 'Global market overview' and enumerating covered asset classes, and the second sentence crediting Yahoo Finance. Every word adds value with no 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 the tool's simplicity (zero parameters, no output schema, no annotations), the description adequately conveys the data scope and source. It could mention the return format, but for a broad snapshot tool with low complexity, the provided detail is largely sufficient.

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 has zero parameters, and the input schema is empty. The baseline score of 4 applies because there are no parameter semantics to enhance; the description correctly does not attempt to explain nonexistent 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 clearly identifies the tool's scope as a global market overview, listing specific indices, cryptos, FX rates, and ETFs. However, it lacks an explicit verb such as 'fetches' or 'lists', and does not differentiate itself from the similarly named sibling tool egx_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?

The phrase 'Global market overview' implies usage for obtaining a broad market snapshot, but there is no explicit guidance on when to choose this tool over alternatives like market_sentiment or egx_market_overview. No exclusions or alternative suggestions are provided.

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