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

Annotations already tell the agent this is read-only, idempotent, and safe. The description adds meaningful behavior beyond that: it explains what fields appear depending on detail, identifies the token field as a chaining ID for lend_deposit, and frames lending as a passive-return strategy. This is solid supplementary context for an already well-protected tool.

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?

Four compact sentences: purpose, row structure, per-parameter detail behavior, and workflow context. Every sentence adds information, and the main purpose is front-loaded. No filler or repetition.

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 there is an output schema and all annotations declare a safe read-only operation, the description covers the essential remaining context: what data is returned, how detail changes the payload, downstream chaining via token, and fit within the workflow. Nothing crucial is missing for selection and invocation.

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%, so the description carries the burden. It explains detail='concise' vs 'full' and the exact fields dropped, which goes well beyond the bare schema. caller_id is not described, but it is optional and its name is self-explanatory, so this is a minor gap rather than a blocking one.

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 a specific verb-resource pair: 'Compare supply/borrow rates across Kamino + Marginfi.' It also lists exactly which fields each row contains, and it explicitly related to get_lst_yields, making the tool's role in the toolset 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?

The description places this in a workflow ('YIELDS step -- the passive-return option for idle/low-conviction capital') and names related tools (get_lst_yields, get_trading_workflow), which provides strong contextual guidance. It doesn't explicitly state 'when not to use' or the exact decision rule between lending and other yield options, so I'd not give a full 5.

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