get_token_prices

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

No annotations are provided, so the description carries the burden. It discloses the input format and that it returns USD prices, but doesn't mention output structure, error behavior, rate limits, or read-only status. This is acceptable for a simple lookup but not comprehensive.

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?

Two sentences, no fluff. The first states purpose, the second provides formatting directives. Every word adds value.

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 tool with no output schema, the description covers the essential input mechanics well. It lacks an explicit return-structure description, but the phrase 'Current USD price' implies the output. A small gap given no output schema.

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 schema only says 'Comma-separated DefiLlama coin ids'. The description adds meaningful examples ('coingecko:bitcoin' and 'ethereum:0x...'), showing both accepted forms and clarifying the chain:contract pattern, which goes beyond the schema.

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 opens with 'Current USD price for one or more tokens', providing a specific verb+resource and clear scope. It distinguishes itself from sibling tools (get_chains_tvl, get_protocol, get_yield_pools, etc.) by focusing on token pricing.

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?

It explicitly teaches the caller how to format the input, including examples of both supported formats. It does not explicitly state when not to use the tool or name alternatives, but the purpose is unambiguous and the usage context is clear.

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