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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds genuinely new behavior beyond the annotations: result ordering ('the default first') and the organizational scoping of the API key. It stops short of pagination or volume hints, so it falls just shy of full marks.

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?

Three tight sentences, each earning its place: purpose and ordering first, then a definition of the resource, then the follow-up routing. Everything is front-loaded with no filler.

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 zero-parameter read-only list tool with annotations covering safety and no output schema, the description supplies everything an agent needs: what a profile is, that output is default-first, and how to use the result. Nothing required for correct invocation 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?

Zero parameters, so there is no schema semantics for the description to augment, which sets the baseline at 4. The mention of 'without one' concerns the sibling list_accounts rather than this tool's own inputs, so it neither helps nor hurts.

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+resource ('List every profile in your API key's organization') with a clear scope, then defines the domain term ('A profile is one customer or brand'). This distinguishes it from the sibling list_accounts, which the description explicitly references as a different discovery path.

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 gives explicit routing: 'Use a profileId from here for profile-specific tools, or call list_accounts without one to discover connected accounts across the organization.' It names the alternative and the condition that selects it, leaving nothing to inference.

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