Look up a coin

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

Annotations already mark the tool as read-only and open-world. The description adds transparency by specifying the return includes price, trend, and metadata, which is useful beyond annotations. No behavioral traits contradicted.

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 sentence that efficiently conveys the purpose, scope, and identifier options without extraneous 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 the presence of an output schema, full parameter coverage, and informative annotations, the description adequately completes the picture by summarizing the tool's return (core metrics). No gaps remain.

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 baseline is 3. The description restates that contract addresses are supported but does not enrich parameter meanings beyond the schema's 'by', 'chain', and 'identifier' descriptions.

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 action 'Look up' and the resource 'a single coin', explicitly listing the core metrics (price, trend, metadata) and multiple identifier types. It distinguishes from siblings like resolve_coin or get_prices by specifying the scope and data returned.

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 explains when to use the tool by listing identifier types (symbol, name, id, contract), which implies appropriate contexts. However, it does not explicitly state when not to use it or directly compare to siblings like resolve_coin or get_prices.

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