Invite guests

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

Goes well beyond the annotations by disclosing real-world side effects ('they reach real people'), hard quotas (1,000 invites per event, 500 by email), a refusal condition (canceled event), an auth prerequisite (Hosts only), and the meaning of the return field invited_total. This is exactly the context destructiveHint=true and openWorldHint=true imply but do not explain.

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 purpose and the two invite channels are front-loaded, and each subsequent sentence carries distinct operational information (limits, refusals, return value, permissions). No sentence merely restates the name or the schema.

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 destructive, open-world mutation with no output schema, the description supplies everything an agent needs: valid input sources, quotas, failure modes, permission requirement, and the meaning of the single returned count. Nothing material is left to inference.

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 100%, so the baseline is 3, but the description adds genuine meaning: user_ids must come from list_past_guests, emails carry a name 'the invite greets,' and message is the personal note delivered with the invite. The phone-sign-in note further clarifies why email invitees still need a phone number.

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?

Opens with a specific verb and resource plus its two delivery modes: 'Invite past guests and mutuals through Partiful, or anyone by email.' This clearly separates it from siblings like approve_guests, send_text_blast, and export_guest_list without the agent needing to open 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 routes the agent to source lists (user_ids from list_past_guests, emails for anyone else) and states an exclusion: phone numbers cannot be invited, only Partiful's app takes phone contacts. It also gates on 'Hosts only.' It stops short of naming sibling alternatives (e.g. approve_guests for pending requests), so it is clear context rather than a full when/when-not matrix.

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