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

Annotations already establish read-only, idempotent, non-destructive closed-world access. The description adds important behavior beyond them: Pro/Max entitlement with 403 plan_required otherwise, rounded amounts, and anonymized trader identity via handle and PnL band. It still omits freshness, ordering, and pagination, so not a 5.

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?

Two compact sentences, front-loaded with scope and then access and output qualifications. Every clause adds useful information; no repetition 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?

The description covers access gating and some return-value characteristics, which matters because no output schema exists. However, it does not state the time window, ordering, pagination, or full result shape, and it gives no sibling routing, so an agent lacks some context needed to interpret results.

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%, including minUsd allowed values and smart flag semantics, so the schema carries parameter meaning. The description adds no parameter-specific guidance and only speaks to output-side rounding and anonymization. Baseline 3 is appropriate.

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 the resource concretely: large taker fills across the whole market, not just "radar". It is clear what the tool returns, but it does not explicitly contrast with the sibling fills tool or explain when radar is preferable.

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 implied by "large taker fills across the whole market" and by plan gating, but there is no explicit when-to-use or when-not guidance versus fills or leaderboard. An agent can infer the large-fill use case, but must infer alternatives.

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