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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds the auth requirement ('Needs sign-in') and scopes the reveal count to 'this week', both of which are behavioral facts the annotations do not carry.

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 tightly packed sentence plus a short prerequisite clause, with the resource front-loaded and no filler. Every listed item (plan, reveals, shortlists, saved searches) earns its place as a return-value preview.

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, the description carries the burden of saying what comes back, and it does list the returned content plus the auth requirement. The only gap is that it does not clarify the overlap with my_saved_searches / my_saved_listings, which an agent choosing among these tools would want.

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 and the schema is fully self-describing, which is the baseline-4 case. The description adds nothing about parameters because there is nothing to add, and it correctly implies the account is inferred from the session rather than passed in.

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 names the specific resource (the signed-in person's account) and enumerates what that account view contains: plan, weekly seller-reveal balance, shortlists, saved searches. That is concrete rather than tautological, but it never distinguishes itself from siblings like my_saved_searches or my_saved_listings, which also surface saved-search/list data.

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 closing 'Needs sign-in' gives one prerequisite, which is useful. However, there is no statement of when to prefer this overview over the more specific sibling tools (my_saved_searches, my_saved_listings), so usage is only implied.

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