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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds real behavioral context beyond them: an empty collection is the expected result when no membership exists, meaning the agent should not treat an empty list as an error.

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 short sentences, both load-bearing: the first states scope, the second states the empty-result behavior and the recovery path. No preamble or restatement of the title.

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 explaining the return, and it does so at least for the empty case. It never says what a populated result contains (identifier, name, role), so the agent knows when it is empty but not what it can extract when non-empty.

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 there is nothing for the description to disambiguate. Baseline 4 applies; the empty-schema situation is handled correctly.

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 gives a specific verb and resource ("List the organizations this sign-in belongs to") and scopes it to the caller's own memberships, which distinguishes it from business-search siblings like find_business. It does not, however, reconcile the name (list_subjects) with the term "organizations," nor distinguish it from select_subject, so an agent must infer that a subject is an organization.

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?

It supplies a clear calling context (fetch the memberships tied to the current sign-in) and an explicit follow-up branch: when the result is empty, call setup_account before claiming a business. It stops short of naming select_subject as the downstream consumer of these results, so the routing between the two is left implicit.

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