Protocol fees

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds genuinely useful behavioral context: the data source (DefiLlama) and its nightly refresh cadence, which tells the agent the data is cached and not real-time. It does not describe return format or any rate limits.

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?

A single tight sentence with the resource and time granularity front-loaded and no wasted words. It is efficient, though the data-source parenthetical could be seen as slightly secondary information.

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?

There is no output schema, and the description does state the return shape (per-protocol fees plus totals) reasonably well. However, with 0% parameter coverage it omits how chain filtering and limit/pagination behave, which an agent needs to call the tool correctly.

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 full burden for the two parameters. It never mentions 'chain' or 'limit', leaving the agent to guess that chain scopes results and limit caps the number of protocols returned. The time windows mentioned are output dimensions, not parameters.

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 names a specific resource (protocol fees) with its granularity (by protocol) and time windows (24h/7d/30d) plus totals, so the agent knows exactly what data comes back. It does not, however, explicitly differentiate itself from near siblings like top_defi_protocols, chains_tvl, or dex_volumes.

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?

There is no explicit when-to-use guidance, no statement of when NOT to use it, and no named alternative among the many DeFi/TVL siblings. The agent can only infer usage from the tool name and the parenthetical time windows.

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