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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the safety profile is covered. The description adds meaningful context beyond annotations: authentication requirements, where members create API keys, what output data is exposed, and how strategyIds feed back into subsequent calls.

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: one dense sentence describing the return payload and strategy narrowing, followed by a short authentication note. It is somewhat run-on but front-loads the core result and contains no obvious 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 nine parameters, rich schema coverage, and no output schema, the description does enough by explaining the returned count, strategy cards, and property signals. It also covers the API-key requirement and strategyIds reuse, though it leaves the choice between sibling tools implicit.

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 parameter meaning is already well documented. The description reinforces the strategyIds workflow and narrowing behavior, but does not add much beyond the schema and does not mention recipientMode or the location alternatives.

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 what preview_market returns: a measured count, strategy cards, and measured property signals for a trade and area. It is specific enough to distinguish this preview/strategy-selection operation from a simple count, though it does not explicitly name or contrast the sibling tools.

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 gives useful context that strategyIds can be sent from a previous preview_market answer to narrow results, and states the API-key prerequisite. However, it does not explicitly say when to use this tool instead of count_homes or start_checkout, nor when not to use it.

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