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

Annotations already declare readOnly, idempotent, openWorld, and non-destructive behavior, so the description does not need to repeat these. The added source note (CoinDesk Data) provides minor context. No contradictions with annotations, but the description adds little extra behavioral transparency beyond what annotations provide.

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 single, compact sentence that efficiently lists the data fields and the direction of the mapping. It is well-structured and to the point, with no superfluous information.

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?

Given that the tool has an output schema (though not shown in the provided snippet), the description does not need to detail the return structure. It provides sufficient context for the data source and the scope of the snapshot. However, it could be slightly more explicit about the multi-pair capability being a list of symbols and currencies.

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 description states 'fsyms → tsyms' indicating a mapping from crypto symbols to currency codes, giving a hint. However, it does not explain the optional 'e' parameter at all, and the parameters have no schema descriptions. The description partially clarifies the direction but leaves key semantics ambiguous.

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 tool fetches a full market snapshot for multiple crypto pairs, enumerating the specific data points (price, 24h change, volume, market cap, open/high/low). It distinguishes itself from simpler price tools by emphasizing 'full' and 'multiple' pairs.

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 implies usage when a comprehensive snapshot is needed (including volume, market cap, etc.) rather than just price, and it supports multiple cryptocurrency pairs. However, it does not explicitly contrast with sibling tools like 'price' or 'price_multi', so the guidance is implicit rather than explicit.

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