directus_aggregate_items

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

With no annotations provided, the description carries the full disclosure burden but only minimally satisfies it. While 'aggregate' implies read-only behavior, the description does not confirm this, nor does it disclose return format, performance characteristics, or whether the operation triggers any side effects.

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 description is compact at one sentence, but the '[UNIFIED]' prefix adds metadata noise without clarifying scope. The extreme brevity is inappropriate for a five-parameter tool with complex nested objects, resulting in underspecification rather than efficient communication.

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?

Given five parameters including complex nested objects (aggregate, filter, groupBy) and no output schema, the description should explain return value structure, aggregation syntax, and filtering capabilities. It addresses none of these, leaving critical gaps for implementation.

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 0%, requiring heavy compensation from the description. While it lists valid aggregation operations (count, sum, etc.), it fails to explain the structure of the 'aggregate' parameter object, the syntax for 'filter' strings, or the purpose of 'site' and 'collection' parameters.

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 clearly identifies the tool performs aggregate operations (count, sum, avg, min, max) on items, specifying both the action and target resource. However, it fails to explicitly differentiate from sibling query tools like directus_list_items or directus_search_items, leaving the selection criteria implicit.

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 guidance provided on when to use aggregation versus retrieving raw items, nor any mention of prerequisites like collection existence or field types required for numeric aggregations. The agent must infer usage from the operation name alone.

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