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

With no annotations present, the description carries the full behavioral disclosure burden. It warns that the client must be authenticated and that start_login is not a shortcut, which addresses the most likely failure mode. It does not describe response details, but for a zero-parameter list tool the access behavior is the key risk.

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?

The description is compact: two short paragraphs, three sentences total, all load-bearing. The core purpose is front-loaded, and the access note adds necessary operational context without repeating schema or annotations.

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 no-parameter tool with no output schema, the description adequately covers the return scope, authentication requirement, and a critical non-behavior. It does not explicitly contrast with get_my_profile or list_profile_templates, but an agent has enough information to invoke it correctly.

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 has zero parameters and schema description coverage is 100%, so there is nothing for the description to add about parameter semantics. The baseline of 4 applies because no parameter documentation is needed.

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 uses the specific verb 'List' with the resource 'profiles' and scopes it to the authenticated account, clarifying that it returns all profiles including primary and secondary. This clearly distinguishes it from singular-profile siblings like get_my_profile or get_profile.

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 description states the prerequisite clearly: a Proof account and authentication are required before the tool will work. It also gives an explicit exclusion—start_login does NOT open this tool—which helps an agent avoid a common wrong path, though it does not name alternative list/get tools.

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