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

With no annotations, the description carries the full burden and does disclose one important trait: no wallet and no signature are required, implying a public unauthenticated read. It also names the underlying GET endpoint, reinforcing read-only semantics. It omits staleness/refresh cadence, rate limits, and whether prices are cached, which matter for a 'live' price feed.

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?

Three short sentences, front-loaded with what the tool returns, which is the right ordering. The raw endpoint path 'GET /api/prices' adds little for an agent and is the one sentence that doesn't fully earn 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 tool this covers purpose, auth requirements, and a deployment caveat, which is nearly enough. However, with no output schema the description should say more about the return shape—e.g., whether it is a list of coin/price pairs and which coins are included—and it says nothing about how fresh 'current' prices are.

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 takes zero parameters, so there is nothing to disambiguate; baseline is 4. The description correctly implies no filtering or symbol selection is possible and that the result set is fixed to the coins shown on Escrova.

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?

States a specific verb and resource: current USD prices of coins shown on Escrova. An agent can immediately tell this is a price lookup rather than anything covered by the sibling tools (categories, deals, fees, terms, products). It doesn't explicitly name a sibling it is not, so it falls just short of a 5.

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?

Usage is only implied: an agent infers it should call this to see current coin prices, and the note that checkout takes USDC only hints at why prices matter. There is no explicit when-to-use, when-not-to-use, or named alternative among the siblings.

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