mfp_set_tracked_nutrients

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

Annotations already convey that the operation is non-read-only, non-destructive, idempotent, and open-world. The description adds no additional behavioral context (e.g., side effects, permission requirements, or impact on diary data). It does not contradict annotations, but also does not go beyond them, so a baseline score of 3 is appropriate.

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 sentence that immediately states the core purpose and includes a helpful example. The '[stable]' marker is extraneous but harmless. There is no waste; information is front-loaded and directly actionable.

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 setting tool, the description covers the essential purpose, and the output schema and annotations handle return values and safety. However, it does not mention any edge cases (e.g., invalid nutrient names, behavior when fewer than 6 are provided) or note that the operation only changes the diary view. Still, given its simplicity and available schema, it is reasonably 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 description coverage is reported as 0%, so the description must compensate. However, it only mentions 'up-to-6 nutrients' and gives an example, without listing valid values or explaining constraints. The schema itself does provide a list of nutrient IDs, but since coverage is 0% per context, the description fails to adequately explain parameter meaning.

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 action ('Choose') and the resource ('nutrients shown in the diary'), and gives a concrete example ('swap Sugar for Fiber'). It is unambiguous what the tool does, though it does not explicitly contrast with sibling tools—none of which are directly similar, so this is a minor gap.

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 provides no guidance on when to use this tool versus alternatives, nor any exclusions or prerequisites. It does not mention related tools like mfp_set_nutrient_goals or mfp_set_goals, leaving the agent to infer usage context. This is a clear omission.

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