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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely non-obvious behavior beyond that: results come from the same saved snapshot as the site's pool cards, the window is 7 days, freshness and confidence accompany the numbers, and estimates are explicitly not promises (fees not guaranteed, no wallet or token needed). That is meaningful added context on a read-only tool, so it clears the lower bar rather than exceeding it.

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 dense paragraph that front-loads the core definition before enumerating presets and per-preset outputs. Every clause carries information (preset widths, units, edge cases, disclaimer), though the tail-end disclaimer and freshness notes push it slightly long for one parameter.

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 fully compensates by naming each returned field: per-preset price bounds in B per 1 A, APR %, in-range volume share, fees per day at the $1,000 card basis, plus best-APR preset, window, freshness and confidence. An agent has enough to call it and interpret the response without further documentation.

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 coverage is 100% and the single poolId parameter is already documented, which sets the baseline at 3. The description goes slightly further by constraining valid values to listed pools from list_rwa_pairs on Raydium or Meteora, which tells the caller this is not an arbitrary address lookup.

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 ("Estimated 7-day fee APR of one listed pool") plus its scope: the 4 named range presets with their exact widths. It also pins the input domain (poolAddress from list_rwa_pairs, Raydium or Meteora), so an agent can distinguish it from position-level siblings without opening the 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?

Gives clear context for invocation: supply a pool address obtained from list_rwa_pairs, and it returns pricing per preset. It also documents the degenerate cases (new pools with too few days, missing snapshots) that yield a status with a reason and no APR. It stops short of explicitly contrasting itself with get_position_performance or get_position_range_status, so there are no stated exclusions.

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