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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so safety is covered. The description adds genuine interpretive context the annotations cannot: the sign convention for net flow and the fact results are ranked by net USD flow rather than raw volume.

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?

One front-loaded sentence states purpose, output shape and sign semantics, followed by a single concrete example call. No sentence is redundant and nothing important is buried.

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, the description carries the burden of describing returns and does so (tokens ranked by net USD flow, positive/negative meaning). Minor omissions such as the default limit of 20 or that results are a bounded ranked list are left entirely to the schema.

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%, so chain, limit, timeframe and _apiKey are all documented in the schema itself. The description reinforces the timeframe concept ('over a time window') and supplies an example call, but adds no syntax or constraints beyond the schema — baseline 3 applies.

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?

It states a precise verb and resource: ranks tokens by net USD flow from Nansen 'Smart Money' wallets over a time window, with sign semantics (positive = accumulation, negative = distribution). It implies but never explicitly contrasts with the sibling nansen_smart_money_holdings, so an agent must infer the holdings-vs-flow distinction.

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 framing question ('What is smart money buying or selling on chain X') signals the use case, but there is no explicit when-to-use / when-not guidance and no named alternative among siblings (e.g., nansen_smart_money_holdings for positions rather than flow). Usage is implied rather than directed.

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