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

Annotations provide readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is fully covered. The description clarifies that the result is scoped to 'Agent Pro' requests specifically, which narrows the tool's domain beyond what annotations state. Given strong annotation coverage, the description adds reasonable additional context about the tool's scoped domain.

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 focused sentence that states the tool's function, source domain (Agent Pro), and required input (upgrade identifier). Zero wasted words and perfectly front-loaded with the key action 'Return the current state.'

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?

This is a simple 1-parameter, read-only, idempotent status-check tool with a full schema, output schema, and comprehensive annotations. The description covers the tool's purpose and scoping adequately. It could name the sibling request tool inline for clarity, but the schema already references account_request_upgrade as the identifier source, and a status tool at this complexity doesn't need extensive behavioral disclosure.

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%, and the single parameter upgrade_id is well-documented in the schema ('The upgrade identifier from account_request_upgrade'). The description adds that the status is queried 'by upgrade identifier,' reinforcing the parameter's purpose but not adding new semantic detail beyond the schema already provides. 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 states it returns the current state of an Agent Pro request by upgrade identifier. It has a clear verb (return) and resource (state of an Agent Pro request), but it doesn't differentiate from siblings like account_request_upgrade, which is its direct counterpart. The purpose is reasonably clear for a status-check tool.

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 it's used to check the status of a previously made upgrade request ('by upgrade identifier'), referencing account_request_upgrade as the source of the identifier. This indirectly connects to the request tool but doesn't explicitly state when to use it vs. alternatives or what conditions warrant checking status.

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