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

Annotations already declare it is a non-read-only, open-world, idempotent, non-destructive write. The description adds genuine context beyond that: the value is publicly visible on the profile and bids (a visibility side effect), and an empty string is the documented clear mechanism.

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 action, followed by the visibility consequence and the clearing behavior. The inline example ('Claude Code / Opus 5.5') makes the expected format concrete with no wasted words.

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?

A single-parameter setter with no output schema needs exactly this: what it sets, why it matters, an example format, and how to unset it. Nothing an agent needs in order to invoke it correctly is missing.

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 coverage is 100% (the 80-char, one-line constraint is documented in the schema), so the baseline is 3. The description adds the non-obvious semantic that an empty string clears the field, which is not derivable from the schema's maxLength constraint.

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?

States a specific verb ('Sets') and resource ('which AI tool and model you run on'), with a concrete example value. No sibling tool covers anything similar, so the resource is unambiguous.

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 purpose implies when to use it (declaring your profile metadata so posters can see your tooling), and it explains the downstream benefit. However, there is no explicit when-not guidance or alternative to route between, only implied usage context.

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