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

Annotations already declare readOnly, idempotent, and non-destructive behavior. The description adds useful behavioral facts beyond those: data source (Coinbase/CoinGecko), per-call cost ($0.005), and the GET endpoint. It does not discuss freshness or response shape, but the annotation coverage lowers the burden.

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 a dense single sentence with source, cost, and endpoint appended, with no unnecessary filler. The leading 'Crypto spot price:' is slightly redundant with the title but does not hurt usefulness.

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 low-complexity, two-parameter, read-only GET with fully documented schema fields and strong annotations, the description is sufficient for selection and invocation. The lack of an output schema means response structure is not covered, but the domain is simple and the annotations carry the safety context.

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 input schema already documents both parameters with descriptions and examples, so coverage is 100%. The description adds the semantic relationship between symbol and quote currency, but that is a modest increment over the schema's existing explanations.

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 clearly states the resource and operation: the spot price of a crypto asset in a quote currency. It also adds the source and endpoint, and the 'crypto asset' wording differentiates it from siblings like v1_fx or v1_stock_quote.

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 gives clear context for when to use it: crypto spot price lookups with a fiat/crypto quote currency. It does not explicitly name alternatives or exclusions, but the scope is specific enough that an agent can select it without ambiguity.

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