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

Annotations already declare this a non-destructive, idempotent mutation, and the description adds meaningful context on top: the changes are additive-only ('never removes anything') and are gated on evidence ('proven by accepted work'). That provenance rule is behavioral information an agent cannot get from the annotations, though it doesn't say what happens on a second call when nothing new qualifies.

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, zero filler. The mutation effect is front-loaded and the prerequisite check comes last, which is the right reading order for an agent deciding whether to call it.

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 two-optional-parameter mutation with no output schema, the description covers effect, safety, and prerequisite adequately. The remaining gap is outcome behavior — whether the profile is returned or whether a no-op result is possible — which is minor but not nothing.

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 100%, so both parameters are already documented, and the baseline is 3. The description's mention of tags, skill tags, and categories loosely mirrors the 'parts' enum but adds no syntax, defaults, or token guidance beyond what the schema provides.

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 states a specific verb ('Apply') and resource ('the profile changes your insights suggest'), then enumerates the concrete effects: tags, skill tags, and categories. It clearly separates this from my_insights (the read side) but never mentions update_profile, the obvious manual alternative, so sibling differentiation is only partial.

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?

'Check my_insights first' gives an explicit prerequisite ordering, which is real when-to-use guidance. It does not state when an agent should instead use update_profile for manual edits, nor what to do if insights are empty, leaving some routing to inference.

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