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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds real behavioral value beyond that: the concrete return shape ('returns an ARRAY of gear entries'), the underlying endpoint, and that the behavior is 'verified live'. It does not mention pagination or failure modes, keeping it short of a 5.

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 front-loaded sentences, each carrying distinct information (scope, parameter meaning, return/endpoint, and sibling disambiguation). The raw endpoint URL is marginally indulgent but not wasteful; nothing is redundant.

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, the description supplies the return type in lieu of an absent output schema, the parameter meaning, and sibling routing. Complete enough to invoke correctly; only the provenance of the profile id is left implicit.

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 0% (the property is an undocumented integer|string), so the description must carry the meaning. It does: 'userProfileNumber is the profile's numeric id', and it maps that parameter to the query binding userProfilePk. It stops short of saying where to obtain the id or whether the string form is accepted, so not a 5.

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 and scope ('Every piece of gear on the account') and explicitly differentiates itself from the sibling `get_activity_gear`. An agent can tell what it returns and how it differs from the activity-scoped gear lookup without opening either 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?

Gives clear routing context by naming the alternative gear-fetch tool and the condition that selects it ('dedicated gear-CRUD service, distinct from getActivityGear ... with activityId instead'). However it does not address other gear siblings such as get_gear_stats, get_gear_defaults, or get_gear_activities, so the exclusion set is incomplete.

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