Get global market overview

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

Annotations already indicate readOnlyHint=true and destructiveHint=false, and the description adds valuable context by specifying the exact metrics returned (market cap, volume, BTC/ETH dominance, counts). This goes beyond the basic safety profile, though it does not disclose potential limitations or rate limits. No contradiction with 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 a single sentence that is concise, information-dense, and front-loaded with the core purpose. It lists all key outputs without unnecessary verbosity.

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 low complexity (one optional parameter, output schema provided, annotations present), the description is complete enough. It clearly states what the tool does and the specific data it returns, meeting all needs for agent selection and invocation.

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 fully describes the only parameter (vs_currency) with a clear description and default value, so the description does not need to add parameter details. The baseline of 3 applies given the high schema coverage.

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's purpose with a specific verb ('Get') and resource ('aggregate statistics for the whole crypto market'), and enumerates the specific metrics returned. This distinguishes it from sibling tools that focus on individual coins or lists, such as get_coin_details or list_top_coins.

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 implies usage for market-wide aggregate statistics but does not explicitly state when to use this tool instead of alternatives like list_top_coins or get_coin_price. There are no explicit exclusions or alternative recommendations, so the guidance remains implicit.

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