Tile region

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

Given no annotations, the description fully carries the burden and excels: it discloses the clamp at 100x100 with truncated:true, the separate sparse liquids list, fog-of-war tiles never painted over, the self-describing legend, and the 'no fort loaded' error. It also clarifies that the grid is depth-blind. This is far more than typical behavioral disclosure.

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 long but every sentence earns its place. It is front-loaded with the core purpose, then systematically covers glyphs, liquid data, fog of war, optional parameters, clamping behavior, facts-only nature, read-only status, and error handling. There is no fluff or redundancy; the density is justified by the tool's complexity.

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?

With no output schema and no annotations, the description must explain return values and edge cases. It does: it describes the legend, the grid contents, the liquids list, the truncated/requested fields, the default window, and the error case. The description offers a complete mental model for an agent to use the tool safely and 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?

Although schema coverage is 100%, the description adds substantial meaning beyond the schema: it explains that all parameters are optional, what the default 60x40 window is, how passing z alone recenters on that level's centroid, and how an oversized request is clamped. This enriches the parameter semantics significantly, making it worthy of a 5.

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 opens with a specific verb+resource: 'A bounded window of ONE z-level rendered as an ASCII character grid plus a self-describing legend.' This clearly distinguishes it from sibling tools like map_overview or environment, and it goes on to enumerate exactly what is rendered and what classes of buildings are shown.

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 clear context on when to use the tool, including default behavior with no parameters, optional z-level focusing, and explicit rectangle selection. It also states exclusions: it is read-only, facts-only, never suggests layouts, and never shows per-building detail. However, it does not name alternative tools or directly contrast with them, stopping short of the explicit alternatives guidance needed for a 5.

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