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

Annotations already cover the safety profile (readOnlyHint=true, idempotentHint=true, destructiveHint=false), so the description adds value beyond them by disclosing operational facts: no auth required, the 1-2 indicator code cap, and the CC BY-SA 4.0 attribution/share-alike obligation. It does not describe response size or pagination behavior, which the schema partly covers via the geo_unit note.

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 definition is front-loaded with the core purpose, then the discovery prerequisites, then a concrete example, then access/licensing facts. Each sentence carries information, though the licensing clause adds length that could be trimmed without losing much.

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?

An output schema exists, so return-value explanation is not required. Combined with annotations, the description covers the essentials an agent needs — discovery prerequisites, filtering options, auth requirements, and license terms — with only minor gaps around expected response volume.

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 all seven parameters are already documented with their own examples and constraints (including the 'can be large' warning on geo_unit and the discovery pointer on indicator). The description's example (indicator='LR.AG15T24', geo_unit='IND', start=2015, end=2022) largely restates what the schema provides, so the baseline 3 applies.

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 uses a specific verb ('Fetch') with a precise resource ('time-series values for 1-2 UNESCO Institute for Statistics indicator codes') and states the domain of coverage (education, science, culture, demographic statistics). It is easily distinguished from its in-namespace siblings unesco-data.reference.indicator_search and unesco-data.reference.geounit_list, which it explicitly routes to for code discovery.

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?

It gives clear prerequisites — call unesco-data.indicator_search first to confirm a valid indicator code and unesco-data.geounit_list to confirm geo_unit codes — and names those siblings as the discovery path. It also states the optional filtering context (geo unit and year range), though it offers no explicit 'when not to use this tool' condition.

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