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

Without annotations, the description bears the full burden of behavioral disclosure. It mentions filtering by TVL and APY, but does not explain the default sorting order, whether results are live or cached, how 'top' is determined, or any limitations. This leaves significant behavioral ambiguity.

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, well-structured sentence that is easy to parse and directly states the tool's purpose. It is appropriately concise for the core function, though it omits supporting details that would improve usability.

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 tool has 4 parameters, no annotations, and no output schema, the description is incomplete. It does not explain what the output looks like, what the filters mean in practice, or how to interpret the results. The single sentence is insufficient for an agent to reliably use the tool without additional inference.

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 description coverage is 0%, and the description does not mention any of the four parameters (limit, min_apy_pct, max_apy_pct, min_tvl_usd). The description adds no meaning beyond the parameter names themselves, so it entirely fails to compensate for the lack of schema documentation.

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 identifies the tool as returning 'Top DeFi yield opportunities on BNB Chain' with filtering by TVL and APY. This distinguishes it from the sibling tools (e.g., bnb_gas, bnb_protocol_tvl) by focusing on yields rather than gas or aggregate TVL. The verb is implied rather than explicit (e.g., 'list'), but the resource and scope are clear.

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?

No guidance is provided on when to use this tool versus alternatives. The description implies usage for finding yield opportunities, but does not mention when to prefer this over bnb_overview or bnb_protocol_tvl, nor any prerequisites or data freshness caveats.

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