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

The description discloses behavioral traits beyond annotations: 'Counts against the weekly invite limit; sends real emails/push' aligns with destructiveHint=true and adds specifics. It also states 'host only' as a prerequisite. No contradiction with annotations.

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 sentences, front-loaded with core action and options. Every sentence adds value: first describes what and how, second mentions limits, third gives prerequisites. No wasted words.

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 the tool has 10 parameters and no output schema, the description covers the essential aspects: purpose, recipients, delivery methods, optional features, limits, and requirements. Minor omission of dry_run behavior, but overall sufficient for an agent to understand invocation.

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?

With 0% schema description coverage, the description adds meaning for major parameters: recipient types (recipient_uids, distribution_list_ids, external_contacts), delivery method, custom message, promo code, scheduling, and community linking. It misses dry_run, but overall compensates well for most of the 10 parameters.

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 description clearly states the tool sends invitations to a live event via app, email, or both, specifying recipient types (people, saved lists, manual contacts). It distinctly separates this from sibling tools like add_guest or invite_team_member by focusing on the invitation delivery process.

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?

The description tells when to use the tool (to send event invitations) and includes important constraints: counts against weekly invite limit, sends real emails/push, requires event_id, and host only. It does not explicitly mention alternatives but the context of siblings implies this is the primary invitation tool.

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