get_field_aggregation

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only mentions that counts, sums, averages, etc. are returned, but omits critical behaviors like default metrics (count), the need for valueField with non-count metrics, default limit of 20, time range handling, and exact match behavior. This is insufficient for a complex aggregation tool.

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 brief and front-loaded with the core action. It is two sentences with no fluff, though the phrase 'etc.' is vague and the second sentence somewhat restates the first. Still, it is efficiently sized for the clarity it provides.

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 11 parameters, nested objects, no output schema, and no annotations, making it high complexity. The description does not explain return structure, required valueField for non-count metrics, default limit, or relationships among parameters. It is too minimal to fully prepare an agent for correct usage.

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 the baseline is 3. The description adds examples of aggregate types (counts, sums, averages) that correspond to the metrics parameter, but does not explain relationships between parameters (e.g., valueField required for sum/avg/min/max) or defaults beyond what the schema already states. It adds marginal value over the schema.

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 states the tool aggregates log messages by field values with statistics like counts, sums, and averages. It identifies the action (aggregate) and resource (log messages/field values), but does not explicitly differentiate from sibling tools like get_field_time_aggregation or list_field_values, so it misses the sibling differentiation point.

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 is given on when to use this tool versus alternatives, such as get_field_time_aggregation for time-based aggregation or list_field_values for simple value listing. The description implies a use case but provides no explicit context or exclusions.

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