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

Annotations already declare readOnly, idempotent, openWorld, and non-destructive, so the safety profile is covered. The description adds real domain behavior beyond that: it scopes coverage to 7 chains, explains the utilization-above-optimal mechanism that spikes borrow APY, and discloses that frozen/paused market state is surfaced.

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?

Front-loads the return contents and scope before the edge-case note and the example queries, so the first sentence already answers what the tool does. The five example questions are longer than strictly necessary but each maps to a distinct query shape, so no sentence is pure filler.

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 enumerated, yet the description still names the key fields. Filters, chain coverage, and the optional-parameter behavior are all covered; the only omission is any note on data freshness or refresh cadence for what is inherently time-sensitive live rate data.

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%, with both optional filters documented including case-insensitivity and omit-for-all semantics, so the baseline is 3. The description's chain list re-confirms the enum but adds no format or syntax detail beyond what the schema already states.

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?

States a specific verb and resource (returns Aave V3 market utilization rates, supply APY, borrow APY across 7 named chains) and adds the frozen/paused status dimension. An agent can distinguish this from siblings like calculate_health_factor or simulate_liquidation, which are position-level tools, without opening either schema.

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?

Explicitly frames usage with 'Use this when asked:' followed by five concrete example questions covering per-asset, per-chain, cross-market, rate, and frozen-market intents. It never names a competing tool or states a when-not-to-use condition, which keeps it short of a 5.

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