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

With no annotations, the description carries the burden and does disclose meaningful behavior: the invite is an email, it expires in 3 days, and it creates/grants team membership. It stops short of stating required privilege level (admin/account holder), what happens on a duplicate invite for an existing member, or whether an invite can be revoked, which matter for a mutation of this kind.

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 short sentences, each earning its place: capability, precondition, and exclusion. The purpose and the sibling exclusion are front-loaded 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 an 8-parameter, 4-required mutation with no annotations, no output schema, and low schema coverage, the description is adequate on intent but thin on mechanics. An agent still cannot tell from the definition what confirm_invite_team_member or limit_visible_apps/visible_app_ids do or that role assignment affects scope.

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 only 25% across 8 parameters, so the description must compensate and it does not: it never mentions confirm_invite_team_member (the required confirmation gate), visible_app_ids, limit_visible_apps, or the name/email fields. Only asc_roles is partially self-documented in the schema, leaving the majority of parameters with no semantic guidance anywhere.

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 user to your App Store Connect team') with the delivery mechanism and timing ('email invitation, 3-day expiry'). It explicitly distinguishes itself from the nearest sibling, invite_testflight_testers, so an agent can choose without opening either 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?

Gives an explicit when-to-use condition ('Required for internal TestFlight when they are not already a team user') and an explicit when-not ('Does not replace invite_testflight_testers (external beta emails)'). The two siblings that could be confused are separated by named intent.

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