List TestFlight testers

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

readOnlyHint=true and openWorldHint=true already tell the agent this is a non-mutating, externally-scoped read, so the description's burden is light. It adds that results include invite state, which is genuinely useful, but says nothing about pagination behavior or the fact that omitting all filters surveys the whole account.

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?

A single front-loaded sentence naming the resource first, then the filters, then the returned attribute. Zero filler; it is slightly terse for a five-parameter filtered list but nothing is wasted.

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?

With five all-optional parameters, no output schema, and no required-parameter anchor, the agent needs to know how filters interact and what happens with none supplied. The description covers the filter dimensions but leaves combination and default-scope behavior unaddressed.

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 100%, so appId, email, betaGroupId, limit and cursor are all documented in the schema, making baseline 3 appropriate. The description echoes three of the five parameters without adding combination semantics or clarifying that limit/cursor drive pagination.

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 (List) and resource (TestFlight testers) plus the filter dimensions and that invite state is returned. It is clearly distinguishable from mutating siblings like invite_beta_tester and remove_beta_tester_from_groups, though it never names those siblings 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?

Usage is only implied: the agent infers 'call this to enumerate testers, optionally filtered.' There is no statement about when to prefer this over list_beta_groups or list_users, and no guidance on whether filters are optional or combinable.

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