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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behaviorate, so the description is not required to restate safety. It adds valuable context beyond the annotations: the data source endpoint (api.uis.unesco.org), no auth requirement, and the CC BY-SA 4.0 license. It does not describe rate limits or pagination, but those are not critical given the safe read-only nature and schema details.

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?

Four short sentences deliver a large amount of information: scope, size, themes, search modes, usage order, example, data source, auth, and license. Every sentence earns its place, and the core action is front-loaded. No filler or repetition.

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?

The tool has zero required parameterscars, an output schema exists, and the description covers the essential workflow context (when to call it, example usage, source, and legal terms). Given the presence of a detailed input schema and output schema, nothing critical for correct invocation is missing.

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 coverage is 100%, so the baseline is 3. The description goes beyond the schema by giving a concrete example of how to use the query and theme parameters together ('query='literacy' or theme='EDUCATION''). It also clarifies that the limit is relevant to narrowing large result sets, though this is already implied in the schema's description.

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 opens with the verb 'Search' and clearly identifies the resource: the UNESCO Institute for Statistics indicator catalog, including its size (~5,063 codes) and thematic scope. It also states the search capabilities—by name, code, or theme—and the intended outcome (finding a valid indicator code). This fully distinguishes the tool's purpose and uses specific language.

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 description explicitly tells the agent to call this tool before unesco-data.get_data, providing a clear ordering and a workflow context. It gives concrete example inputs (query='literacy', theme='EDUCATION'). However, it does not state when not to use it or mention any alternative search tools, so it stops short of a full exclusion/alternative set.

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