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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered elsewhere. The description adds only that filtering is optional, saying nothing about result ordering, what happens when no filter is supplied (all years?), or the response shape. Adequate but thin beyond the annotations.

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?

A single front-loaded sentence with the resource first and the optional filter second. No filler, nothing 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 two-optional-parameter, read-only list tool with full schema coverage and a complete annotation set, this is nearly sufficient. The only real gap is the default behaviour when neither filter is supplied and how results differ from the sibling libur_* tools.

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%: both parameters carry descriptions ("Month 1-12", "Year (e.g. 2026)"). The description restates that year and month are the filter axes but adds no semantics such as default range or how a month alone is interpreted. Baseline 3 applies when the schema already does the work.

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 gives a specific verb and resource ("List Indonesian public holidays") plus scope (optionally by year/month), so an agent knows exactly what it returns. It does not name or distinguish itself from the closely related siblings libur_get and libur_upcoming, which keeps it below a 5.

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?

The phrase "optionally filtered by year and/or month" implies how to use the parameters, but there is no explicit guidance on when to choose this over libur_get (single holiday) or libur_upcoming (upcoming holidays). Usage is inferable but never stated.

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