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

Annotations indicate readOnlyHint=true. The description reinforces this with 'Read-only: members, roles, teams and SSO are not changeable through MCP by design — a human does those in the web app,' adding context about the design rationale. No contradiction exists.

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 description is two sentences that directly state the purpose, usage condition, and read-only nature. It avoids fluff and is well-structured with a clear first sentence on function and a second on constraints.

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?

Given the tool has no parameters and no output schema, the description covers the function, the usage context (organization members), the alternative (list_teams), the requirement (organization context), and the read-only nature. This is sufficient for an agent to decide when to call it.

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?

The tool has no parameters, so the schema covers all parameters (100%). The description does not need to add parameter semantics, and indeed does not mention any parameters. The mention of 'organization context' is a usage requirement rather than a parameter explanation.

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 description clearly states that the tool lists organization members with their role, custom role, join date, and last login. It also distinguishes itself from list_teams, making its purpose unambiguous.

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 explicitly says 'Use this for the organization's members' and contrasts with 'for the teams they belong to use list_teams.' It also notes 'Requires organization context,' providing clear when-to-use and when-not-to-use guidance.

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