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

No annotations are provided, so the description must carry the burden of behavioral disclosure. It does disclose the payment requirements (PAY: $0.01 via x402, retry with PAYMENT-SIGNATURE header) and the need to handle 402 challenges, which is critical. However, it does not disclose other behaviors like rate limits, whether the tool is read-only, or what happens if no districts are at a bottom. Since annotations are absent, this gap prevents a higher score.

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 description is compact yet information-dense, with only a few sentences covering purpose, payment, cold-start advantage, and sibling differentiation. It is front-loaded with the primary action and output. Every sentence 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 tool with a single optional parameter and no output schema, the description is remarkably complete. It explains what it returns, how it ranks, the payment process, and how to handle errors. No critical information is missing for an agent to call it effectively.

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 description coverage is 100%, so the only parameter 'limit' is fully described in the schema (default 5, max 25). The description does not add extra meaning beyond that, but with full schema coverage the baseline is 3. It could have clarified whether limit=0 or larger values have special meaning, but not needed.

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 clearly states the specific verb ('Scan') and resource ('all 25 Seoul districts'), and the output ('those currently at a bottom, ranked most-bottom first, with price-per-pyeong'). It is immediately distinguishable from siblings like 'scan_tops' and 'evaluate_symbol' by focusing on bottoms across the entire universe.

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?

Explicitly says when to use: 'BEST COLD START: you do not need to pick a symbol — this ranks the whole universe for you.' It also contrasts with the free 'pitch' tool: 'tells you HOW MANY are at a bottom right now; this names them.' This provides clear when-to-use and when-not-to-use guidance among siblings.

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