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

readOnlyHint=true already establishes this is a safe read, and the description adds genuinely useful context beyond that: the default active-records scoping, the free-text search coverage, the full filtermode vocabulary and the underlying GET /members endpoint. It does not mention pagination limits or sorting behavior, but those are covered by the schema.

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 dense sentences, front-loaded with the resource definition and search scope before the filter detail. Every clause carries information, though the filtermode enumeration is a long inline list that borders on schema duplication.

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 does not explain the return shape, but it compensates with resource semantics, default scoping and the endpoint. Pagination and sorting are left to the fully-documented schema, so an agent has enough to call this correctly.

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 baseline would be 3; however the description adds real meaning by listing the searchable fields and the complete set of filtermode values (including with_pending_activities, with_live_opportunities, bookable) that the schema's generic 'e.g.' description omits.

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 (members), and crucially explains that a 'member' is Current RMS's unified record type for Organisations, Contacts, Venues and Users — a semantic clarification an agent cannot infer from the name alone. It is easily distinguishable from get_member, create_member and update_member siblings.

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 states the default behavior ('Defaults to active records') and enumerates the filtermode values, which effectively tells the agent how to scope the query. It does not explicitly contrast this with get_member for single-record retrieval, so it stops short of full when-not/alternatives guidance.

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