measurements_create_head_circumference

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

With no annotations provided, the description carries the full behavioral burden, but it only says 'Record a head circumference measurement.' It does not disclose that it creates a new entry, any validation behavior, or what response to expect. The verb 'Record' only weakly implies creation, and the 'create' in the tool name is the main signal.

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 a single, front-loaded sentence that states the core purpose with no filler or redundant phrasing. It is as concise as possible while still conveying the essential action.

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 simple create tool with a fully described schema and an output schema, the core purpose is covered. However, it lacks any usage context, such as when a head circumference measurement should be recorded or any relationship to other measurement types suggestions. The absence of usage guidance leaves a gap in completeness.

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 schema already documents all parameters with types, formats, and helpful hints (e.g., 'Use list_children to get IDs'). The description adds no parameter information, but that is unnecessary given the schema's completeness. Baseline of 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 clear verb ('Record') and a specific resource ('head circumference measurement'), which distinguishes it from sibling create tools for height, weight, or BMI. The resource noun makes the tool's purpose unambiguous and differentiates it from list/update/delete variants.

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 measurements_update_head_circumference or other measurement creates. There are no prerequisites, exclusions, or context cues like 'for new measurements' or 'if the child has no existing head circumference entry'.

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