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

Rich disclosure beyond the annotations: the two possible statuses, the invite email's origin and signing safety, the hourly resend limit, and specific error codes (STATE_CONFLICT, NO_OPERATOR, OPERATOR_AMBIGUOUS, RATE_LIMITED) with their fallback behaviors. This is exactly the kind of side-effect and precondition detail an agent needs before a non-idempotent, open-world mutation.

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 key action and status outcomes are front-loaded, which is good, but the whole thing is one dense paragraph and the fallback clause '(an alias or id add then invites without the email)' is repeated verbatim twice. The content earns its place, but the packaging does not.

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?

An output schema exists so return values needn't be spelled out, yet the description still covers permissions, side effects, rate limits, and every refusal condition. For a destructive, non-idempotent membership mutation, nothing an agent needs in order to call it safely is missing.

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 already 100%, so the baseline would be 3, but the description adds real meaning: it explains that alias/id adds only email when exactly one verified person is behind the account, and that email adds depend on a single verified sender. That behavioral differentiation of the 'member' argument goes well beyond the schema's plain type and maxLength.

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 opening clause gives a specific verb and resource ('Add someone to a team') plus the accepted identifier forms, so the action is unmistakable. It does not distinguish itself from the nearby sibling workspace_member_add, so an agent must still decide between team and workspace membership on its own.

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?

Clear operating context is given: 'any member may add', self-added accounts become 'member' immediately, everyone else is 'invited', and STATE_CONFLICT is returned when the account is already a member — effectively telling the agent when the call will not work. No sibling is named as the alternative for role changes or removals, so the comparison is inferred rather than explicit.

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