add_calc_group_format

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

With no annotations, the description carries the full burden. It discloses key behaviors: use of SELECTEDMEASURE(), per-item format strings, and creation of the calc group if absent. But it omits what happens if the group already exists, any permissions required, or potential 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 three focused sentences, front-loaded with the essential concept, and free of unnecessary details. Every sentence contributes to understanding the tool's purpose and behavior.

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 tool with no annotations and no output schema, the description covers core functionality, item structure, and table creation behavior. It lacks details on precedence semantics and behavior when the group already exists, making it good but not complete.

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 covers 75% of parameters with detailed descriptions (including an example for items). The description adds semantic context about items preserving value and using format strings, but this is largely redundant with the schema's 'items' description. No significant new parameter guidance is provided.

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 builds a calc group that overrides displayed format as a currency/%/scale switcher. It distinguishes itself from generic calc group tools by specifying the exact mechanism (items keep value but reformat) and provides a concrete example via the schema.

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 identifies the use case ('currency / % / scale switcher') and explains that items preserve the value while reformatting, which implies when this tool is appropriate. However, it does not explicitly name alternatives or state when not to use it.

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