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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds genuine scope information about what the payload contains and what is deliberately omitted, but nothing about auth/permission needs or the shape of the preset list beyond its existence.

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?

Two sentences, front-loaded with the payload contents, followed by a precise boundary statement about the excluded resolved gram targets. Every clause carries information; nothing is redundant with the schema or annotations.

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?

With no input parameters and no output schema, the description does the heavy lifting by enumerating the returned fields and pointing at the tool that holds the excluded ones. It is largely complete for a simple read, missing only return-shape detail such as how presets are structured.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate and the baseline of 4 applies. The text correctly adds no parameter chatter, though it could have clarified what the single-user scope implies for callers.

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?

Concretely names the resource: the signed-in user's macro philosophy/targets (protein floor, carb cap) plus available presets. It also implicitly distinguishes itself from the day view, which carries resolved per-day gram targets, so an agent can tell what this tool does and does not return.

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 second sentence effectively states when this tool is the wrong one: if you need resolved per-day gram targets including fat, the day view carries them as `macros`. That is a clear routing signal, though it never names the sibling tool explicitly and gives no converse 'use this when' framing.

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