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

With no annotations, the description carries the burden and does disclose the main behaviors: optional coin prices with defaults, fear-and-greed index, and gas. It leaves unspecified details such as gas network, coin-list format, pricing currency, and output structure.

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 compact and front-loads the tool's purpose before the parameter instruction. The only waste is the near-duplicate 'Crypto Brief:' prefix preceding 'Crypto brief'.

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 simple one-optional-parameter aggregator, the description is mostly adequate and tells the agent what data the brief includes. Without an output schema, though, it leaves the return shape, units, and chain/currency context implicit.

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 already covers the sole parameter at 100%, so the baseline is 3; the description adds that coins are optional and default to bitcoin,ethereum. It does not clarify whether the list is comma-delimited or another format, but the added default and optionality are useful.

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 states a useful aggregation: one call returning coin prices, fear-and-greed index, and gas. This distinguishes it from single-purpose siblings like x402-crypto-price, x402-fear-greed, and gas tools, though it never uses an explicit verb like 'get' or 'generate'.

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?

'Crypto brief in one call' implies the tool should be used when the user wants a combined snapshot instead of separate calls, and it explains the coins parameter default. However, it never explicitly names alternatives or states when not to use it.

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