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

Annotations already establish readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds genuinely new context: the $0.003 per-call cost, that results include a DefiLlama outlier flag, and an explicit caveat that this is not a risk rating. That is meaningful interpretation and cost context beyond the structured fields.

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 return contents are front-loaded, which is good, but the phrase "Not a risk rating" appears twice, the second time redundantly redundantly tacked onto the usage sentence. That repetition wastes space and slightly muddies an otherwise tight definition.

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 no output schema and five zero-coverage parameters, the description should carry more weight than it does; chain, limit, and the boolean flag semantics are unaddressed. It does describe returned fields and cost, which helps, but an agent still lacks enough to fully configure the call.

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% across five parameters, so the description must compensate. It implicitly covers stable_only ("stablecoin or all") and min_tvl ("TVL floor") and touches the outlier flag, but chain and limit are undocumented anywhere, leaving half the parameters unexplained.

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 gives a concrete verb-and-resource picture: it returns DeFi pools filtered to a TVL floor, with APY, 30-day mean APY, reward-token share, and an outlier flag. That is far more than a restatement of the name. It stops short of explicitly differentiating from siblings such as stablecoin_supply or the carry_* family, so it is clear but not fully self-routing.

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?

"Use for stablecoin pool APYs; not a risk rating" gives a positive usage cue and a boundary (not a risk assessment), which is useful. However, no alternative or sibling tool is named for when this is the wrong choice, so the guidance is implied rather than explicit.

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