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

With no annotations, the description carries the burden and does well: it discloses the confirm-gating, the permission requirement (owner/admin), and that omitting roleId clears the role. It does not describe reversibility, failure behavior, or return format, hence not a 5.

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?

Two tight sentences, front-loaded with the core action, then the authorization and caution. No filler; 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?

For a 4-param mutation with no annotations and no output schema, the description covers purpose, permissions, gating, and a caution to confirm targets. Return/result behavior is left implicit, but the essentials for correct invocation are present.

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 coverage is only 25% (only confirm is documented), so the description must compensate. It adds key semantics for roleId (omitting it clears the role), but says nothing about memberUserId or organizationId beyond their obvious names.

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 (assign/clear) and resource (custom role for a gym member), and explicitly covers both directions of the operation, including that omitting roleId clears the role. The word 'custom' distinguishes it from the sibling update_organization_coach_role.

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 the condition for use (owner or admin performing an access-control change) and a clear instruction to confirm which member and role first. It does not name alternative siblings or state explicit when-not conditions, but the context is clear.

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