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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description goes slightly beyond the annotation by enumerating the exact data categories the profile contains (body measurements, HR zones, health conditions, injuries), which is useful behavioral context for what the agent can expect. The bar is lower due to annotations, and this description adds relevant scope context without contradiction.

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?

A single, efficient sentence that front-loads the verb and resource, then enumerates the result categories in a compact list. Every word earns its place; there is no filler or redundancy.

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 parameterless read-only tool with a full output schema and clear annotations, the description is fully complete. An agent needs nothing more to decide when to call it and what to expect from 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?

There are zero parameters, so there is no input schema to disambiguate. The description fully compensates by telling the agent exactly what data will be returned, making it clear there is nothing else needed to invoke the tool. With 0 params, the baseline for this dimension is 4, and the description exceeds it by specifying the result content.

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 a specific verb ('Get') and identifies a distinct resource ('the user's profile') with a concrete list of what it contains: body measurements, HR zones, health conditions and injuries. This clearly differentiates it from siblings like get_activity or get_schedule, and from the write-oriented update_profile, without needing to open the schema.

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 conveys a clear context: it is a read-only retrieval of profile information. It does not explicitly state when to prefer this over siblings such as list_custom_metrics or report_injury, but given zero parameters the tool is unambiguous in its scope. There is no exclusion guidance, so I cannot rate above a 3.

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