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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false), and the description adds genuinely useful context beyond them: that notes and limitations are NOT shared with the client (a privacy/visibility property) and that a Cotlet API key with app access is required. It stops short of describing pagination or response structure, but adds real behavioral value.

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?

Content is front-loaded, but the middle is redundant: the first sentence lists the fields and the second sentence re-lists nearly the same fields ('Returns what the client overview page shows: profile, goals, limitations or injuries, your private notes...'). One of these sentences could be cut without losing information.

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?

With no output schema, the description correctly carries the return-value burden by enumerating the fields, and it discloses the auth requirement. For a single-parameter read tool this is nearly complete, missing only pagination/error behavior that is unlikely to matter here.

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% and the single parameter is already documented ('Client ID from list_clients'), so the schema carries the burden. The description adds no syntax or format detail beyond the schema; baseline 3 applies.

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 and resource ('Get client') and then enumerates the exact payload (profile, goals, limitations/injuries, private notes, 7/30-day workout counts), which cleanly separates it from the sibling everfit_list_clients. An agent can tell it returns one client's overview page rather than a roster.

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 client_id is sourced from list_clients, so the relationship to that sibling is implied, but there is no explicit when-to-use or when-not-to-use guidance and no naming of alternatives such as everfit_list_clients or everfit_get_body_metrics. Usage is inferable rather than stated.

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