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

Annotations already declare readOnlyHint and idempotentHint, so the safety profile is covered. The description adds meaningful behavioral context beyond annotations: the profile 'follows them across companies' and defaults to the caller unless member_id is passed. This helps the agent understand scope and default resolution.

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 sentences, each earning its place: what it returns, when to use it, and how the parameter default works. The most important information is front-loaded before the parameter note.

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?

Even without an output schema, the description compensates by naming the output dimensions ('character level + per-topic strengths') and possible levels. Combined with annotations for safety and complete schema coverage, nothing essential is missing for an agent to call this 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?

Schema description coverage is 100%, so the schema already documents both parameters well. The description mostly restates the member_id default ('Defaults to the caller') rather than adding new semantic detail. Per the baseline for high schema coverage, a 3 is appropriate.

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 names a specific verb and resource ('Get a person's OPERATOR FLUENCY (reader profile)') and concretely defines the output as 'overall character level + per-topic strengths (novice/fluent/expert).' This clearly distinguishes it from siblings like get_voice_profile or update_reader_profile without needing to inspect schemas.

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 clear usage context: 'Use before writing cards/FYIs so speech matches their level.' It also explains the default caller behavior and how to target another person. It stops short of explicitly naming alternatives or when-not-to-use conditions, so it earns a 4 rather than a 5.

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