Prepare an App Store version

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

Annotations already declare readOnlyHint=false, idempotentHint=true and destructiveHint=false, but the description adds real behavioral detail beyond them: metadata is copied from the previous version, an in-progress version may be renamed, and the write flag is required. The one gap is that it doesn't say what the call returns or how the rename branch affects an already-submitted version.

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?

Front-loaded with the core behavior, then a separate sentence for auth and idempotency. The parenthetical about Apple copying metadata is high-value and every clause 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 7-parameter mutation tool with no output schema, the description covers prerequisites, side effects and re-run safety well. It stops short of describing the result of a successful preparation (e.g. the created/renamed version identifier), which an agent may need to chain into submit_for_review.

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 71%, so most parameters are already documented. The description adds semantics for the build attachment and release type, but says nothing about earliest_release_date, platform defaults, or dry_run beyond what the schema states, so it only marginally exceeds the schema baseline.

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 names a specific verb (prepare) and resource (App Store version) and enumerates the three concrete branches the tool takes: reuse an existing version, rename the currently prepared one, or create a new one. No sibling tool (submit_for_review, get_listing, etc.) overlaps, so the agent can route to it without ambiguity.

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 states the operating prerequisite (changes App Store Connect, needs ASC_WRITE=1) and that re-running is safe, which tells the agent when invocation is allowed. It doesn't explicitly name a sibling alternative or a when-not-to-use case, but no sibling competes for this job, so the guidance is adequate.

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