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

Annotations correctly declare this as a non-destructive, non-idempotent write (readOnlyHint: false, destructiveHint: false, idempotentHint: false). The description adds critical behavioral context not in annotations: it requires owner privileges and describes role capabilities. However, it does not mention the 26-character constraint or side effects like notifications.

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 tightly written sentences with zero waste. The most critical constraint (Owner only) is front-loaded, followed by role semantics and the fallback path.

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 two parameters, no output schema, and explicit annotations, the description covers purpose, permissions, role meanings, and an alternative tool. It is complete for invocation, though it omits expected outcome (e.g., success response or errors).

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 0%, so the description must supply parameter meaning. It clarifies that 'user_id' must be a known 26-character ID and defines the 'role' enum values (owner, editor, viewer). This compensates well for the schema's lack of descriptions.

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 (add) and resource (member) with scope ('this workspace') and references the required user_id. It is clearly distinguishable from siblings like remove_member, set_member_role, and invite_teammate.

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?

Explicitly states 'Owner only', describes the permission scope subject to role, and names the alternative for unknown user IDs ('use invite_teammate instead'). It explains the role meanings to help select the correct role parameter.

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