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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered; the description still adds real value with cost/auth ('Free, no payment or key; the same answer as the free Ethos API') and pagination behavior. It also discloses the returned fields and an example payload, which is well beyond what the annotations provide.

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?

The purpose is front-loaded in sentence one and the routing advice follows logically, but the definition carries a bulky inline example output payload that dominates its length. Since no output schema exists the example has value, yet the full JSON blob is heavier than needed to convey the return shape.

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 compensates by enumerating returned fields (credibility score, status, linked wallets, social accounts) and showing a concrete response with total/limit/offset. Combined with the free/no-key note, an agent has everything needed to call this correctly for a 3-parameter read tool.

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 query, limit and offset are already documented, and the baseline is 3. The description reinforces the accepted fragment types (name, partial handle, part of an address) but adds no syntax, matching rules, or paging semantics beyond what the schema states.

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 first sentence names a specific verb (find/search) and resource (person or project on Ethos) and states the discriminating input condition: 'when you only have a name, a partial handle or part of an address'. That condition implicitly but effectively separates it from the identifier-exact siblings ethos_user_by_address and ethos_user_by_x.

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?

It gives an explicit workflow trigger ('The starting point when a user asks about someone by name: search, pick the match, then score or profile it by userkey') and a secondary use case (disambiguating impersonators). It stops short of naming sibling tools or stating when NOT to use it, e.g. when an exact address or X handle is already known.

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