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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false and destructiveHint=false, so the safety profile is fully covered without the description. The description adds nothing beyond that - it does not say what happens when the id is unknown (error vs empty) or what a province object contains. For a simple read tool with complete annotations this is adequate but not additive.

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?

One short sentence with the resource and key front-loaded; every word earns its place and there is no padding. It is arguably too terse for the tool's needs, but nothing is redundant.

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 one-parameter read-only lookup with full annotation coverage and no output schema, the definition is complete enough to call correctly: resource, key, and example are all present. Remaining unknowns, such as not-found behavior, are minor for a tool of this simplicity.

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% and the single id parameter is documented with a concrete example ("11" for Aceh), so the schema does the heavy lifting. The description only restates that lookup is by id, adding no format, validation, or fallback detail beyond the schema.

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 verb and resource ("Get a single province") plus the lookup key ("by its id"), which implicitly separates it from wilayah_list_provinsi and wilayah_search. It does not name a sibling explicitly, so an agent must infer the single-vs-list distinction from the word "single".

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?

Usage is only implied: "by its id" signals a direct lookup when the id is already known, and "single" hints that listing tools exist elsewhere. There is no explicit when-to-use, when-not-to-use, or named alternative such as wilayah_list_provinsi or wilayah_search.

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