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

Goes well beyond the readOnlyHint/openWorldHint annotations by disclosing that this is a frozen cached snapshot at a specific commit verified on a specific date, that data derives from GeoNames under Unlicense, and that it costs no points. The privacy_consent_required error path is useful behavioral context, though the phrasing 'if you supply fields' is confusing when country is the only and required field.

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 purpose is front-loaded, but four sentences carry provenance, licensing, cost, and a consent caveat with visible repetition ('does not... does not...'). The privacy-consent sentence is the least useful relative to its length and is ambiguous about when it actually fires.

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 single-parameter read-only snapshot lookup, the description covers provenance, freshness, and cost well. With no output schema, though, it never says what comes back (a list of division names? codes? nested levels?), which is a real gap for an agent planning to consume the result.

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 0% and there is a single required parameter, yet the description never mentions it, its expected format, or an example. Only the schema's '^[A-Z]{2}$' pattern hints at an ISO-style two-letter code; the description contributes nothing to disambiguate valid values or casing.

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?

Names a specific resource and scope: 'First-level divisions for one country' from a named dataset, and explicitly disclaims being a live geocoder, which separates it from sibling hub_geocode. The verb is only implied ('returns'), and the sentence is padded with commit hashes and license provenance, which slightly dilutes the core statement.

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?

'This is a cached file read, not a live geocoder' gives an implicit use condition but never names hub_geocode as the alternative for live lookups, nor states when this snapshot should be preferred over it. 'Does not spend points and does not accept a URL' narrows expectations but is not when-to-use guidance.

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