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

Adds substantial context beyond the annotations: the agentic planning over real administrative boundaries, the return shape (GeoJSON plus per-part sources), the 422 failure mode explaining unmapped text, latency of 30 s to minutes, and an auth requirement (API key or connected account). The one gap is that 'create' implies a persisted resource, but the description never says whether the area is stored in an account, retrievable later, or reusable — relevant since readOnlyHint is false.

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?

Four sentences, front-loaded with the core transformation, then output, then latency, then the routing alternative and auth. Each sentence carries distinct decision-relevant information with no repetition of the title or schema.

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, the description compensates by naming the return format and error case. Combined with latency, auth, and the alternative path, an agent has everything needed to decide and call correctly for a slow, open-world, non-idempotent generation tool.

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 description coverage is 100%, so the schema already documents all four parameters including the seed point constraint and country code. The description only reinforces the meaning of `text` via an inline example; it adds nothing about seed semantics, the source field, or how country scopes the mapping. Baseline 3 is appropriate.

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 transformation (plain-language description → one validated land-only polygon) with a concrete example input, and explicitly contrasts itself with search_boundaries + get_boundary for simple lookups. An agent can distinguish this from every sibling without opening the schema.

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 an explicit alternative and the condition that selects it ('For a single named place use search_boundaries + get_boundary instead'), even quantifying the tradeoff as instant and 1 unit versus minutes here. Also states the input sources it accepts (free prose, contract or policy wording), which frames when this tool is the right choice.

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