Expire a build

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

No annotations are present, so the description must carry the disclosure burden. It adds a meaningful behavioral consequence ('can no longer be installed by testers') beyond the title, but it omits side effects such as irreversibility, permission requirements, and impact on testers who already installed the build.

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 sentence that front-loads the action and outcome with no filler and no repetition of schema information. Every word earns its place.

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 one-parameter mutation without an output schema, the description covers the essential operation and its intended effect. It is slightly incomplete on behavioral caveats such as reversibility and permissions, but those are secondary to actually invoking the tool.

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?

The sole parameter buildId is already fully documented in the schema as 'The build resource ID' (100% coverage). The description adds no additional parameter-level meaning, so baseline 3 is appropriate.

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 uses a specific action, 'Mark', names the resource ('a TestFlight build'), and states the goal ('can no longer be installed by testers'). This clearly distinguishes it from read-oriented siblings like list_builds and get_build, as well as from review-submission tools.

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 implies the trigger for use—when a build should stop being installable—but it does not state prerequisites, cautions, or cases where expiration should not be used. No sibling tool covers expiration, so the usage context is self-evident but not made explicit.

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