invite_beta_tester

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

Adds substantial context beyond annotations: a real email is dispatched, the write may need an explicit user confirmation, and the confirmToken is single-use and only valid after user approval. It also flags a prompt-injection risk explicitly. It does not address reversibility/undo or rate limits, so it stops short of full behavioral disclosure for a destructiveHint=true tool.

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?

Purpose is front-loaded in the first sentence and every clause carries information (side effects, confirmation flow, safety constraint). The final sentence is long and clause-stacked, which slightly hurts readability, but nothing is wasted or redundant.

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 6-param, open-world, confirmation-gated write with no output schema, the description covers the full call lifecycle: what triggers a preview, what the confirmToken response looks like, and when a repeat call is legitimate. An agent has enough to invoke it correctly and safely.

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 baseline is 3; the description goes further by explaining the confirmToken's role in the phase-1/phase-2 flow and the email/build/group parameters' combined effect, which the schema fields alone do not convey as a workflow.

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?

Specific verb+resource: 'Invite a new beta tester by email', with scope clarified ('sends a real email') and optional side effects (beta groups, builds). This is clearly distinguishable from sibling add_testers_to_beta_group (existing testers) and invite_user (App Store Connect users), though neither sibling is named explicitly.

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?

It gives clear conditions for how to invoke the tool: confirmation prompt when the client supports it, otherwise a preview + confirmToken round trip. However, it never states when to prefer this over add_testers_to_beta_group or invite_user, so alternative selection is left implicit.

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