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

Annotations already cover readOnlyHint, openWorldHint and destructiveHint, but the description adds genuinely useful behavioral context beyond them: it discloses the auth requirement ('Needs an agent token') and the return shape ('profile fields (no credentials)'), which is important for a user-listing tool. It stops short of describing rate limits or result caps.

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?

Three short sentences, front-loaded with the purpose and searchable fields before auth and endpoint details. The raw endpoint string (GET /api/v1/users/search?expand=true) is marginally extraneous but still earns its place for debugging, so structure is efficient overall.

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 return-value burden and does so at a high level ('profile fields (no credentials)'), plus it flags the auth requirement. Pagination is handled by the schema (next_page reference), leaving only minor gaps like result ordering or exact field list.

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 all three parameters (query, page, per_page) are already documented in the schema, including pagination defaults. The description's list of searchable fields loosely echoes the query parameter but adds no syntax or format guidance beyond what the schema provides, 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 (search) and resource (users) and enumerates the searchable attributes (name, e-mail, login, phone, organization), so the agent knows exactly what this matches. The resource name distinguishes it from zammad_search_tickets and zammad_search_organizations, though the relationship to zammad_get_user (single lookup vs search) is left implicit.

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 description implies its usage context (find customers/agents by attribute) but never states when to prefer it over zammad_get_user for a known ID or over the organization search. No exclusions or prerequisites for selection are given beyond the implicit 'search vs fetch' distinction.

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