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

With no annotations provided, the description carries the full burden of behavioral disclosure. It usefully discloses that the operation is free and that results are ordered by scanning from the top-left, but it does not explicitly state that the call has no side effects or that it does not claim/reserve any blocks.

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 extremely concise: one short noun phrase for behavior, one clause for ordering, and one word for cost. Every word adds value and there is no redundant information.

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 simple read-only-style list tool with one optional parameter and no output schema, the description adequately conveys output type, ordering, and cost. It could be more explicit about the coordinate format, but nothing essential is missing for an agent to call it correctly.

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 single parameter 'limit' is already fully described in the schema, including its default and min/max bounds. The description adds no parameter-specific meaning beyond confirming the tool returns coordinates, so the baseline of 3 applies.

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 title 'Find unclaimed blocks' and the description 'Coordinates of unclaimed blocks' clearly identify the tool's purpose and output. It is distinguishable from siblings like get_block and get_wall because it specifically addresses unclaimed blocks rather than individual or all blocks.

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 this tool is used to locate free blocks, and the phrase 'Free' suggests there is no cost to calling it. However, it does not explicitly state when to prefer this over alternatives like get_wall or get_block, nor does it mention exclusions.

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