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

Annotations already establish read-only, idempotent, non-destructive safety, so the description is not carrying that burden. It still adds real value beyond them: keyset pagination behavior, scoping to non-deleted ('living') profiles, and the warning that profile fields are respondent-provided and untrusted — a substantive trust caveat.

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?

Dense and front-loaded: the entity, its fields, the filter options, paging model, and a trust warning fit in three tight sentences with no filler. Slightly terse but every clause earns its place.

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 an output schema present, return values need not be described, and annotations cover the safety profile. The description adds filtering, paging, and a trust caveat, making it nearly complete for a read-only listing tool; only explicit routing to sibling listing tools is missing.

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%, so the description must compensate. It clarifies externalId (identify() users), email (as a filter), and cursor (via 'keyset paged'), but says nothing about the limit parameter or its 1–100 range, leaving one of four parameters undocumented anywhere.

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 the specific resource (living respondent profiles = identify() users) and enumerates the returned fields (external id, email, name, traits, verified flag). 'Living' usefully marks it as distinct from deleted-respondent operations and from sibling list_response tools, though it never names an alternative outright.

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?

No explicit when-to-use or when-not guidance. It mentions that you can filter by externalId or email, which implies lookup usage, but it never contrasts with siblings like fillo_list_responses or fillo_get_response, leaving the agent to infer which listing tool applies.

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