tilemap_fill_rect

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 but offers minimal information beyond the basic action. The 'Compatibility tool' label suggests legacy status but does not clarify whether the operation overwrites existing tiles, what the default fill value is, or execution side effects. For a mutation tool with significant undocumented parameters, this lack of behavioral context is inadequate.

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 consists of a single terse sentence with a parenthetical qualifier, containing no redundant or extraneous language. While appropriately brief, it may be excessively concise given the tool's apparent complexity and the undocumented parameter schema. The structure front-loads the action but sacrifices necessary detail for brevity.

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?

The description is inadequate for a tool that appears to require specific geometric and asset parameters not documented in the schema. With no output schema, no annotations, and incomplete input schema coverage, the description should compensate by explaining the fill behavior, expected parameters, and return values, but it does not. The '(Compatibility tool)' note raises questions about the tool's status that remain unanswered.

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 has 0% description coverage for its two defined parameters and uses additionalProperties: true to accept undocumented parameters likely required for the operation (presumably coordinates, dimensions, and tile ID). The description completely fails to mention what parameters define the rectangle or fill value, leaving agents with no guidance on required inputs. Given the schema's incompleteness, this silence on parameter semantics is a critical failure.

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 the tool fills a rectangular area in a tilemap, which provides a clear basic action distinct from siblings like tilemap_set_cell. However, it fails to specify what tile ID or value is used to perform the fill, and the '(Compatibility tool)' parenthetical lacks explanation. While the core verb and resource are present, missing specifics prevent a higher score.

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 provides no explicit guidance on when to use this tool versus alternatives like tilemap_set_cell for individual cells. The '(Compatibility tool)' notation hints at potential deprecation but does not explicitly state whether users should prefer newer tools or what those alternatives might be. Without clear when-to-use instructions, agents cannot make informed selection decisions.

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