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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and external-data behavior are covered. The description usefully clarifies the analytical semantics (grouping by shared funding source), but says nothing about result size, rate limits, or how deep the funding graph is traversed.

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 sentences, front-loaded with the core operation and followed by the use case. No filler, no restatement of the tool name.

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?

For a one-parameter read tool with safety annotations, most of what an agent needs is present. But with no output schema, the description never indicates what the returned cluster looks like (address list, counts, depth limits), which an agent needs to plan the call.

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?

There is a single parameter and schema description coverage is 100%, so the schema already documents 'funder' as a 0x-prefixed address. The description's phrase 'funded by a single funder' echoes the parameter rather than adding format or validation detail, so 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?

States a specific verb ('Detect') and resource (the set of addresses sharing one funder), and defines the underlying concept in parentheses so the agent knows exactly what a 'cluster' means here. It does not explicitly differentiate itself from the sibling tools, but their purposes are unrelated, so the risk of confusion is low.

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?

'Useful for sybil / entity detection' gives a clear analytical context in which to reach for the tool. However, it states no prerequisites, no when-not condition, and no alternative tool to prefer for overlapping investigations.

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