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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description adds real value by enumerating the returned metrics, but says nothing about sorting, pagination, or what happens when limit truncates the result set.

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 front-loaded sentence that leads with the defining filter (two or more exchanges) before listing outputs. Dense but every clause carries information; no boilerplate.

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, listing the returned metrics is necessary and done well. However, for a listing tool with a `limit` default of 30, the absence of any guidance on ordering, pagination, or the group filter leaves an agent guessing about result semantics.

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% and the description never mentions either parameter. The `group` enum (crypto/equity/commodity/index/fx) and the `limit` bounds (1-500, default 30) are only inferable from the raw schema, so the description fails to compensate for the coverage gap.

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 and a precise scope: coins with a perp on two or more exchanges, plus the fields returned (exchange count, open interest, funding APR range, best after-fee pair). That distinguishes it from siblings like coin_overview or funding_rates, though it never names an alternative explicitly.

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?

Usage is only implied: an agent can infer this is the discovery/screener view for multi-venue coverage. There is no statement of when to pick this over coin_overview or funding_rates, and no mention of prerequisites or exclusions.

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