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

Annotations flag destructiveHint=true and idempotentHint=false, but the description adds crucial behavior beyond them: the default is a non-mutating preview and only confirm:true touches real Apple resources, plus explicit idempotency/retry semantics via request_key. This is meaningful context an agent could not derive from the structured fields alone.

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?

The core safety rule (preview default vs confirm:true) is front-loaded and every sentence carries operational weight, but the paragraph is dense with multiple distinct concerns (scope sourcing, supported domains, attestations, retry, routing) that could be more tightly grouped.

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 open-world destructive write with an output schema present, the description covers everything an agent needs: preview/confirm gating, parameter sourcing, idempotency recovery, and sibling routing. Return values are correctly left to the output schema.

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 the baseline is 3, but the description adds sourcing guidance the schema lacks: scope/references come from read_store, operation/body follow get_store_capabilities, and request_key must be reused identically on retry rather than regenerated. That elevates it above a pure schema restatement.

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+resource ('Execute a discovered Apple write using its exact JSON:API body') and enumerates the covered domains (pricing/offers, product creation, replies, release settings, asset reservations). It explicitly distinguishes itself from publish/update_review/manage_testflight, so an agent can route without opening sibling schemas.

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 explicit when-to-use ('execute a discovered Apple write'), when-to-defer ('Use publish/update_review/manage_testflight for their dedicated actions'), a dependency ('Copy scope and relationship references from read_store'), and a recovery rule ('On pending, retry identical arguments with the returned request_key'). Nothing is left to inference.

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