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

With no annotations present, the description must fully disclose behavioral traits. It only mentions 'via CoinGecko,' indicating an external data source, but does not describe any side effects, rate limits, authentication needs, or response behavior. As a price retrieval tool, it is presumably read-only, but this is not explicitly stated. The minimal disclosure leaves significant uncertainty about how the tool behaves beyond its basic function.

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 extremely concise at only four words, which aids quick scanning. However, it sacrifices critical information; every word should earn its place. The brevity here leads to omissions in usage guidelines, parameter semantics, and behavioral details, making it less effective than a slightly longer but more informative description.

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 (2 string parameters, no output schema) and the presence of many similar sibling tools, the description is incomplete. It does not describe the output format, possible error conditions, or example usage. An agent needs more context to integrate this tool reliably, especially without any annotations or schema descriptions.

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?

Schema description coverage is 0%, so the description should explain the parameters. The description does not mention 'coin' or 'currency' at all. Although the parameter names are somewhat self-explanatory, the tool offers no information about valid values (e.g., ticker symbols, full names) or default behavior. This fails to add value beyond the raw schema and leaves the agent with insufficient guidance to use the tool correctly.

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 that the tool retrieves cryptocurrency prices using CoinGecko, establishing a specific verb ('get price') and resource ('cryptocurrency price'). It is not a tautology and distinguishes itself from sibling tools like btc_address_balance and btc_mempool_fees, which serve different purposes. However, it lacks detail on whether it returns current, historical, or some other price type.

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 no guidance on when to use this tool versus alternatives. Given the large number of sibling tools, including other financial tools like currency_rates and polymarket_market_scan, the absence of usage context leaves the agent without clear criteria for tool selection. No when-not or alternative recommendations are provided.

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