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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, but the description adds valuable context beyond them: 'No key required,' 'Rates are variable and not advice,' and the risk-weighted ranking scope. These details help an agent understand authentication needs, data volatility, and selection logic without contradicting any annotation.

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 front-loaded with the core result and then covers filters, caveats, and authentication requirements. It is slightly dense but every sentence contributes meaningful information. No wasted words, though the final two short clauses could arguably be merged without loss.

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?

With an output schema present, return values need not be described in the text. The description covers scope, ranking, filtering, authentication, and risk caveats, making it complete for an agent to invoke the tool correctly. No required information is missing.

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 100%, so the schema already documents all three parameters. The description adds a small amount of extra context by explaining max_risk's letter meaning and filtering behavior, but it does not materially improve on the schema's parameter descriptions. Baseline 3 is appropriate.

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 returns one entry per asset with its best current yield, risk grade, and a comparison link. It names the exact asset classes covered and the ranking methodology, making the tool's purpose unambiguous. With no sibling tools, no differentiation is needed, and the description fully defines what the tool does.

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 gives explicit usage guidance for the max_risk filter and clarifies that no API key is required. It does not list alternative tools or exclusion criteria, but with no sibling tools present, this is not a significant gap. The context is clear enough for an agent to know when to invoke this tool.

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