get_latest_price

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

Annotations already declare readOnlyHint=true, and the description does not contradict that. It adds useful behavior beyond annotations: the exact return fields (date, value, type, source) and the null-when-no-price behavior, which an agent needs to interpret the response correctly.

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 scannable: a one-line summary, a short Args section, and a Returns section. Every sentence contributes useful information, and no filler or repetition is present.

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 read-only lookup tool, the description covers all elements needed to invoke it correctly: required parameters, optional parameter semantics, return shape, and the null case. The read-only safety profile is already in annotations, and the return contract is stated explicitly.

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 carries the full burden of explaining the three parameters. It provides a concrete example for commodity and namespace and clearly explains the currency default and when to pass it explicitly. This fully compensates for the schema's bare names.

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 clear action and object: 'Get the most recent price for a commodity,' with commodity, namespace, and currency parameters. It is specific enough to be distinguishable from price-mutating siblings like create_price and delete_price, but it does not explicitly contrast with get_prices, so it falls short of full sibling differentiation.

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?

No guidance is given about when to choose get_latest_price over get_prices or other siblings. The only usage-related context is the currency default behavior, which explains how the optional parameter behaves rather than when to use this tool versus alternatives.

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