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

No annotations exist, so the description carries the burden, and it does disclose the return shape ('price per unit each way') and the breadth of supported currencies (~35). It does not disclose the rate source or freshness, whether this is a pure computation or a billable call, or how multi-currency conversion is expressed — meaningful gaps for an unannotated 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?

Two tight sentences: capability first, then use cases. Every clause carries information — accepted token formats, currency breadth, and output shape — with no filler.

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?

An output schema exists, so return values need not be described, and the tool is a simple 3-parameter read/compute with defaults. What remains missing is the mechanism for requesting multiple currencies and the source/freshness of the conversion rate, which would matter for accounting use cases the description itself invokes.

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%, and the description partially compensates: it explains that `token` accepts symbols or chain:address and that `to` supports ~35 fiat codes beyond the listed ones. However, it says 'one or more fiat currencies' while `to` is a single string with no enum, leaving the multi-value syntax (comma list? repeated key?) unresolved — the single most important ambiguity for correct invocation.

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 (convert) plus resource (token amount into fiat currencies) and the shape of the result ('price per unit each way'). That is clearly distinguishable from adjacent siblings like crypto_token_prices (raw prices) and fx_rates (fiat-only), which an agent can infer from the crypto-to-fiat framing.

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?

'Use for invoices, accounting or pricing in local currency' gives concrete scenarios that tell the agent when this tool is the right pick. It stops short of naming alternatives or exclusions (e.g., 'for historical prices use crypto_price_history'), so it is clear context without explicit routing.

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