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

Annotations already declare destructiveHint=true, idempotentHint=false and a non-read-only profile, so the safety burden is largely covered. The description adds the useful behavioral fact that input is free-form natural language and that the tool is deprecated, but says nothing about confirmation, partial-failure, or what exactly a swap destroys. Moderate added value against low annotation burden is a 3.

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, ~25 words, with the deprecation/routing guidance front-loaded ahead of the capability statement. Every clause earns its place and nothing is padded.

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 single-parameter, no-output-schema, fully annotated tool, this covers purpose, routing, and input style adequately. It stops short of explaining what the agent sees back after a mutation or how conflicts in a free-text command are resolved, which is a minor remaining gap.

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?

There is only one parameter and schema description coverage is 100%, with the schema already supplying example strings ('add thorne-vitamin-d-k2', 'swap thorne-creatine for momentous-creatine'). The description restates the natural-language input style but adds no syntax, naming, or format constraint beyond the schema, so the baseline 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?

It states a specific verb set and resource ('Add, remove, or swap products in user's supplement stack') and explicitly distinguishes itself from the very siblings it overlaps with (add_to_stack, remove_from_stack, swap_products). An agent can decide whether this legacy tool or a specific sibling applies without opening any 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?

The first sentence is an explicit routing instruction: 'Legacy: prefer suppco_add_to_stack / suppco_remove_from_stack / suppco_swap_products.' It names the exact alternatives by tool id and tells the agent when not to use this tool, which is the strongest form of usage guidance.

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