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

Annotations already cover the safety profile (readOnly=false, destructive=false, openWorld=true, idempotent=false), and the description adds real context beyond them: an invite email is sent, the member joins only on accept, and host permission is required. It stops short of saying what happens on a duplicate invite (error vs. resend) or whether a pending invite must be cancelled first, which is the remaining behavioral gap given siblings like cancel_team_invite.

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 dense sentences, front-loaded with the action, then the requirement, then the sibling routing. Every sentence carries distinct information with no filler.

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 3-param mutation with no output schema, the description covers action, roles, prerequisites, side effect (email sent) and lifecycle (joins on accept). It omits the return value (e.g., pending invite id) and duplicate-invite behavior, which matter slightly given the surrounding invite-management tools.

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 carries the burden, and it does state that all three params are required and maps the enum values to human role names (host=Producer, promoter=Co-Host). It still leaves guest_list and door_person unexplained and adds nothing about what event_id must reference, so it compensates only partially.

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 staff/team member to a live event by email with a role') and enumerates the five valid roles. It explicitly points to list_event_staff / update_staff_role / demote_staff_to_guest for managing existing staff, so the agent can separate this from closely-named siblings without opening a schema.

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 names when to use it (new invite) versus the sibling set for existing staff, states prerequisites ('Requires event_id + email + role; you must be a host'), and notes plan availability ('Available on every plan'). Nothing about selection is left to inference.

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