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

Annotations already establish read-only, idempotent, non-destructive, closed-world behavior, so the description's job is to add context — and it does: it discloses that the call needs no key and burns no quota, but that viewing the map consumes map tiles, and it warns to swap YOUR_KEY for a website-restricted key. Missing only edge details like whether the returned snippet is version-pinned or what the tile_url output looks like exactly.

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?

Two sentences, front-loaded with the deliverable, with no filler. The parenthetical library list is dense but earns its place by mapping libraries to output types; a slightly cleaner structure would separate the key/quota caveat from the output description.

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 two-parameter code-generation tool with no output schema, the description covers what is returned, the library choices, the placeholder key, and the billing implication. A small gap remains around how the style parameter interacts with the tile_url option and what exactly the snippet contains.

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 coverage is 100% with both enums fully described, so the schema already carries parameter meaning. The description reinforces the vector-vs-raster distinction ('MapLibre GL JS vector map, Leaflet or OpenLayers raster map') but adds no syntax or format detail beyond the schema; baseline 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?

States a specific deliverable (ready-to-paste HTML/JavaScript or an XYZ tile URL template) and the resource (interactive MapIron map), enumerating the concrete flavors (MapLibre vector, Leaflet/OpenLayers raster). This clearly distinguishes it from siblings like static_map or privacy_area_map, which produce images rather than code.

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?

Gives clear selection context: use maplibre for a vector map, leaflet/openlayers for raster, and tile_url when the user has 'any other library'. It does not explicitly name sibling tools (e.g. static_map) or state when NOT to request code, so it falls short of full when/when-not/alternatives coverage.

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