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

readOnlyHint=true is consistent with a 'Get' tool, and the description goes beyond the annotation by disclosing the authentication prerequisite and the fact that a failed call should be retried after authenticating. It omits any error/not-found behavior or rate-limit context, so it is good but not complete.

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 tight sentences followed by a clearly delimited ACCESS note; the purpose is front-loaded before the operational caveat. The ACCESS block is slightly verbose relative to the rest but every line is load-bearing.

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 read-only single-parameter tool with no output schema, the description covers what it returns, what it requires, and how to recover from an auth failure. Nothing critical is missing, though sibling routing could be tighter.

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?

Only one parameter and schema coverage is 100%, so the schema fully documents profile_id. The description adds no format, source, or lookup hint beyond what the schema already states, which is the baseline 3 case.

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?

States a specific verb+resource ('Get a specific profile by ID') and previews the payload (theme, custom links, verification display settings). The phrase 'specific profile by ID' implicitly contrasts with the sibling get_my_profile, but it does not name that alternative, so 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?

The ACCESS block gives a real precondition (a Proof account plus client authentication) and warns that start_login does not open this tool, which is genuinely actionable. It says nothing about when to prefer this over get_my_profile, list_profiles, or get_profile_assets, so the use-vs-alternative question is left to inference.

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