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

Annotations only declare readOnlyHint/openWorldHint, but the description adds substantial behavior: role-dependent result visibility (administrator sees all, master sees only their created users, anyone else gets an empty list), that passwords are never returned, and that results are not paginated. The read-only restatement duplicates the annotation but the added context far outweighs it.

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?

Front-loaded with purpose, then read-only confirmation, then usage, then visibility rules, then return shape. Every sentence carries decision-relevant information, including the field enumeration that substitutes for the missing output schema.

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 compensates by listing returned fields, their formats (status role values, yyyy-MM-dd endDate), and the absence of pagination. Permission-scoped visibility and the cross-session business caveat are also covered, so an agent has everything needed to call and interpret this 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 the single optional 'business' parameter is already fully documented in the schema, including cross-references to list_businesses and switch_business. The description touches business scoping indirectly but adds no syntax or format detail beyond the schema, so the 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 (List) and resource (user accounts of the current business) with the scope spelled out. It is immediately distinguishable from siblings like list_businesses, list_names, and current_business without opening any schema.

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?

Gives explicit when-to-use cases (who has access and with what role, finding a user's email or team) and names the alternative for the session user (current_business instead). It also routes business switching to switch_business, leaving nothing to inference.

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