tilemap_fill_rect

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

No annotations are provided, so the description carries the full burden. It does disclose useful behaviors: the rectangle is inclusive and corners can be given in any order. However, it omits other behavioral details such as whether existing tiles are overwritten, how the layer parameter is used, or what the operation returns. It provides some transparency but not comprehensive.

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 a single sentence, front-loaded with the verb 'fill', and includes key behavioral caveats ('inclusive', 'corners in any order') without any wasted words. It is concise and well-structured.

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?

This tool has 10 parameters, no output schema, and no annotations, so the description must carry significant weight. It covers only the basic rectangle-filling concept and corner parameters, but leaves out essential context like node_path, tile atlas coordinates, and layer behavior. The description is too brief for the tool's complexity, resulting in an incomplete picture for the agent.

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 description explains the corner parameters (x1, y1, x2, y2) and their 'any order' property, but it does not clarify the remaining 7 parameters (node_path, layer, atlas_x, atlas_y, source_id, alternative). With schema description coverage at 0%, the description should compensate by explaining the tile-related parameters, but it doesn't, leaving most parameters semantically unexplained.

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 uses the specific verb 'fill' and clearly identifies the resource: an inclusive grid rectangle between two corner points, with the added detail that corners can be in any order. This distinguishes it from sibling tools like tilemap_set_cell (single cell) and tilemap_clear (empty the tilemap).

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 a clear use case: when you need to fill a rectangular region with a single tile. It does not explicitly name alternative tools or state when not to use it, but the context is evident from the operation described. Since it lacks explicit exclusions or alternative mentions, it falls short of a 5 but is above a 3.

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