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

The readOnlyHint annotation already covers the safety profile, and the description adds meaningful behavioral detail: it lists the exact metrics returned (24h/7d/30d volume, period-over-period changes, share of global volume) and the source. It does not contradict the annotations or hide any obvious side effects beyond what a read-only tool implies.

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 two tight sentences: the first front-loads the primary purpose, and the second enumerates the key metrics and filtering/ranking options. Every phrase earns its place with no redundancy or 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 a read-only annotation, a fully documented 3-parameter schema, and an output schema present, the description provides sufficient selection and invocation context. It names the data source, return metrics, filtering options, and ranking window, leaving no obvious gaps for an agent to misuse the tool.

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?

The input schema already provides 100% coverage of all three parameters with clear descriptions, so the description does not add significant meaning beyond the schema. It restates the filtering/ranking semantics, but the schema already documents limit, protocols, and lookback_days accurately, warranting the baseline score.

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 ('Compare') and resource ('decentralized exchange activity from DeFiLlama'), making the tool's purpose immediately clear. It also distinguishes itself from siblings like get_dex_quote and get_protocol_tvl by focusing on volume comparison metrics.

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 clearly establishes when to use the tool (when comparing DEX activity from DeFiLlama) and how to tailor it via protocol filters and lookback windows. However, it does not explicitly name alternative tools or state when not to use this tool, so it stops short of full exclusion guidance.

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