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

Beyond the annotations (which only indicate not read-only, not idempotent, not destructive), the description reveals the mutation semantics ('creates the tracked app'), preview limitations ('masked handles, no contacts'), rate/quota constraints ('one quick-scan app per unpaid account, 6 an hour'), and asynchronous behavior ('Takes 20 to 60 seconds to return... intake runs first'). This gives the agent essential operational knowledge that annotations alone do not provide.

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?

Every sentence earns its place: the first states the core function, the second covers plan/quota constraints, the third preview limits, the fourth the alternative tool, and the fifth the expected latency and next step. The description is dense but not bloated, front-loads the essential purpose, and avoids vague filler.

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?

Given there is no output schema, the description compensates by explaining the full workflow: it creates an app, queues a scan, takes 20–60 seconds due to intake, and directs the agent to call get_quick_scan_preview to retrieve results. It also covers user-tier distinctions and rate limits. An agent can confidently invoke this tool and know what to expect and do next.

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 input schema already describes all three parameters with 100% coverage, so the baseline is 3. The description adds no new parameter-level nuances beyond restating that the URL can be an App Store, Google Play, or website URL, which the schema already covers. It does not elaborate on how kind or market interact with the scan, leaving the schema as the primary source for those details.

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 immediately states the tool's verb and resource: 'Free quick scan of an App Store, Google Play or website URL: creates the tracked app and queues the scan.' This clearly distinguishes it from the sibling start_scan, which is explicitly referenced as the full-scan alternative for paying accounts. The scope and output (tracked app plus queued scan) are unambiguous.

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 gives explicit when-to-use and when-not-to-use guidance: 'No plan needed' and 'Accounts WITH a plan should use start_scan for the full scan instead.' It also instructs the correct follow-up action—'then call get_quick_scan_preview'—so an agent knows the full workflow. This is far beyond a bare statement of purpose.

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