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

With no annotations, the description carries the full burden, and it does disclose the key side effect (an email is sent, containing a signup link) and that the action is confirm-gated. However it omits permissions/auth requirements, whether an invitation can be revoked or duplicated, and what happens to unused invitations — significant gaps for a mutation that sends external email.

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 that front-load the action and recipient, with no filler. The parenthetical '(confirm-gated)' partly duplicates the schema description of 'confirm', but it earns its place as a structural cue.

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 three-parameter tool with no annotations, no output schema, and only 33% param coverage, the description is too thin: it says nothing about expiry behavior, the preview-vs-execute return difference beyond the parenthetical, error cases (e.g., duplicate invite), or required permissions.

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 33%: only 'confirm' is documented in the schema, while 'email' and 'expiresInHours' have no descriptions. The description only alludes to the email recipient ('by email') and never explains the expiry window, so it fails to compensate for the coverage gap.

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 and resource (invite a prospective client by email) plus the scope ('under this coach') and the mechanism (email with a signup link). It implicitly distinguishes prospect-invites from client-invites, but never names the close siblings invite_client_to_organization / invite_coach_to_organization, leaving the agent to infer which invite tool applies.

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?

There is no statement of when to use this versus invite_client_to_organization or invite_coach_to_organization, nor any prerequisites (e.g., must the inviter be a coach, must the prospect already exist via create_prospect). The '(confirm-gated)' note hints at a preview flow but does not route the agent among alternatives.

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