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

With no annotations, the description carries the full burden, and it does meaningful work: it discloses the paid x402/USDC-Base cost ($0.005) up front and documents default behavior (10 majors) and the 25-pair cap. It does not describe the response shape or latency/rate-limit behavior, so the disclosure is solid but not complete.

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?

One compact sentence with the paid-access cost front-loaded, then capability, then defaults and audience. Every clause (cost, batching, default list, target agents) carries information an agent needs; nothing is padding.

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 single-parameter read tool with no annotations or output schema, the description covers cost, defaults, limits, and audience well. It omits what the response actually contains (price fields, timestamps, fiat denomination), which is the main remaining 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?

Schema coverage is 100%, so the single parameter's BASE-QUOTE format is already documented. The description still adds value the schema lacks: the default value (10 majors) and the maximum of 25 pairs, which materially affects 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+resource (multi-asset USD price snapshot) plus scope (up to 25 pairs, default 10 majors) in a single sentence. The phrase 'Batch beats per-pair calls' implicitly separates it from sibling tools like get_crypto_price and get_coin_convert, so an agent can route correctly without opening the schema.

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?

Explicitly targets 'portfolio and dashboard agents' and frames the batch advantage over per-pair calls, which is genuine when-to-use guidance. It stops short of naming the sibling tools it supersedes or stating exclusion cases, so it is clear context rather than a full decision rule.

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