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

Annotations already carry the safety profile (readOnlyHint=true, idempotentHint=true, destructiveHint=false), so the description needn't repeat it. It adds the scope of data returned, but discloses no additional behavioral traits such as data freshness, latency, or whether the metrics reflect real-time or delayed data. Consistent with annotations — no contradiction.

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, front-loaded sentence with zero filler. The main purpose leads, and the four data points are listed compactly. 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, read-only tool with an output schema and rich annotations, the description covers what an agent needs to understand the tool's scope and expected result. The only gap is the absence of guidance for routing to overlapping siblings, but the low complexity keeps the bar modest.

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, so the baseline of 4 applies. The description usefully enumerates what the output includes, compensating for the otherwise empty parameter surface by setting expectations about the returned metrics.

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 names a specific verb ('Get'), resource ('global overview of the cryptocurrency market'), and enumerates concrete content (market cap, 24h volume, Bitcoin dominance, active cryptocurrencies). The 'global' scope helps differentiate it from market-exchanges and market-rates, though it doesn't explicitly name any sibling to compare against.

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?

No guidance is provided on when to choose this tool over its 12 siblings. The word 'global' implies a macro-level use case, but there are no explicit conditions, exclusions, or named alternatives (e.g., when to use market-analysis instead). An agent must infer the boundary from the title alone.

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