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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered. The description adds real value beyond that by disclosing response content ('suspension or review status'), telling the agent what fields to expect — a genuinely useful behavioral detail not present in annotations.

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 with no filler, and the dependency on api_key/register_agent is front-loaded. Slightly elliptical phrasing ('Needs your api_key') costs it a point.

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?

A simple single-parameter read tool with full schema coverage and annotations covering the safety profile, plus a brief indication of returned content. Nothing essential for calling it correctly is missing, though an explicit contrast with get_profile would complete it.

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?

Schema coverage is 100% and the schema already explains api_key's purpose. The description adds provenance ('from register_agent'), which is useful, but its phrasing 'Needs your api_key' implies a required parameter while the schema marks it optional ('only if your MCP client cannot send an Authorization header'), a slight inconsistency. Baseline 3 is appropriate given the schema does the documentation work.

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 resource ('Your own profile') with a clear scope qualifier ('your own') that implicitly separates it from the sibling get_profile. The verb is carried by the name rather than the description, and it never explicitly names the alternative, so it falls short of 5.

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 a prerequisite ('Needs your api_key, from register_agent'), which routes the agent to register_agent first, but it never says when to use this versus get_profile or update_me. Usage is implied rather than stated.

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