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

With no annotations, the description carries the full behavioral burden, and it does add real context beyond the schema: it explains that some rows come from an open-data portal with source_instrument prefixed 'Portal' and no decree number. It does not say what happens for an unknown regency_code, an uncovered region, or an empty history, nor does it confirm the return shape. Partial behavioral coverage.

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 opening clause is well front-loaded, but the bulk of the description is a single run-on sentence enumerating a long province/region/year list. That content is genuinely useful for knowing what data exists, but its unstructured prose form makes it hard to scan and crowds out tool-selection guidance.

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?

There is no output schema and no annotations, so the description must fully specify behavior and returns. It names source instrument and URL but never states whether the actual UMK amount and the year are among the returned fields, which is the single most important thing an agent needs to know. The coverage inventory is thorough, but the return contract is incomplete.

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?

The single parameter is already fully documented in the schema (Kemendagri kabupaten/kota code, with a two-segment numeric pattern), giving a baseline of 3. The description adds no extra meaning about the parameter itself, such as what to do with codes outside the covered regions.

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 states a precise verb+resource: every loaded year of the UMK for one kabupaten/kota, returned oldest first, with source instrument and URL. It clearly delimits the tool to historical UMK series. It never names or contrasts with the obvious siblings get_umk or get_ump_history, so an agent must infer the relationship from the name alone.

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?

No explicit when-to-use or when-not-to-use statement, and no alternative tool is named. However, the exhaustive coverage list doubles as an implicit constraint: it tells the agent that regions/years outside the enumerated set have no data, which helps avoid futile calls. That is useful but inferred, not stated.

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