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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile needs no restating. The description does add one genuinely useful behavioral fact – results are automatically scoped to the signed-in user, so no user identifier is needed – but it says nothing about ordering, completeness (all scheduled doses vs only logged ones), or result shape.

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?

A single front-loaded sentence with the actor, resource, and time scope in that order. No filler and nothing that could be trimmed without losing meaning.

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 output schema, no parameters, and full annotation coverage, the definition is minimally sufficient to call the tool correctly. However, the agent is left guessing what an 'intake log' entry contains and whether the response is granular per-dose or an aggregate summary – relevant given siblings like stackwell_get_nutrient_totals and stackwell_get_day_detail that do aggregate.

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 the baseline is 4. The description reinforces this by explaining that the 'signed-in user' and 'today' dimensions are implicit rather than passable arguments, which matches the empty 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 pairs a specific verb ('Get') with a specific resource ('Stackwell supplement intake logs') and a clear scope ('for today', 'signed-in user'). It is unambiguous on its own, but does not name any sibling (e.g. stackwell_get_day_detail or stackwell_get_adherence) that could return overlapping data, so the agent must infer the boundary.

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 'for today' scope implicitly signals when the tool is appropriate versus a range/productivity tool, but there is no explicit when-to-use statement and no alternative is mentioned. Nothing tells the agent what to call instead if it needs yesterday or a multi-day view.

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