Global market aggregates

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

Annotations already declare readOnlyHint=true and openWorldHint=true, indicating a safe, read-only operation. The description complements this by specifying the exact data returned (BTC dominance, total market cap, total volume), providing full behavioral clarity for a zero-parameter tool.

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, efficient sentence that front-loads essential information. Every word contributes: it names the resource, lists key metrics, and no 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?

Given zero parameters and an existing output schema, the description is complete. It succinctly covers what the tool does without needing to explain return values, as the output schema handles that. No gaps are evident.

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?

There are no parameters, so schema coverage is 100%. The description effectively adds value by naming the output fields, which is especially helpful when no parameters need explanation. Baseline for 0 parameters is 4, but the descriptive output earns a 5.

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 it provides global market aggregates, specifically naming BTC dominance, total market cap, and total volume. This distinguishes it from siblings like get_prices or get_market_health by specifying the exact metrics returned.

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 that this tool is for retrieving high-level market aggregates, but it does not explicitly state when to use it versus alternatives like get_market_health or get_prices. The purpose is clear, but usage boundaries are not delineated.

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