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

With no annotations, the description carries the full burden, and it discloses that prices are live, cached up to 15 minutes, and quoted per troy ounce in USD and CAD. This gives the agent useful behavioral expectations, though it does not describe the exact response shape or field names since no output schema is provided.

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 sentences, all informative and front-loaded with the core purpose, followed by usage guidance and key caveats. No fluff or redundant restatement of the tool name.

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 getter, the description covers the subject metals, currencies, unit of measure, and data freshness. It is slightly incomplete because it does not hint at the output structure or field names, but the lack of parameters and the simplicity of the tool make this a minor gap.

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 has zero parameters, so the baseline is 4. There is nothing for the description to clarify about parameter semantics, and the schema coverage is effectively complete because no parameters exist.

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 specific verb ('Get'), a precise resource (current spot price), and scopes it to silver and gold in USD and CAD per troy ounce. This clearly differentiates it from the sibling calculate_coin_melt and calculate_melt_value tools, which perform calculations rather than retrieve live prices.

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 explicitly says to use this tool for questions about silver spot price, gold spot price, or the USD→CAD exchange rate used in melt value calculations. It provides clear context for when the tool is appropriate, though it does not explicitly state when not to use it or name a preferred alternative.

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