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

Annotations already declare readOnlyHint=true, and the description adds valuable context beyond that: the required scope (hr:employees:read) and the fact that payroll/private fields are omitted. It does not describe the return shape, but without an output schema that gap is minor for a simple read tool.

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 short sentences, front-loaded with the action and resource, followed by the access condition and data-scope caveat. Every sentence carries useful information with no waste.

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 single-parameter read tool with annotations and full schema coverage, the description covers purpose, authorization, and data exclusions. It could be slightly more complete by explicitly directing users to list_employees when the ID is unknown, but nothing essential is missing.

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 fully documented with pattern and format. The description's mention of 'internal numeric ID or documented external reference' restates the schema rather than adding new syntax or constraints, so 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?

The description states a specific verb and resource ('Read operational employee metadata') and clarifies the lookup modes (internal numeric ID or documented external reference). It distinguishes retrieval-by-ID from the sibling list operations, though it does not explicitly name those siblings.

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 implies this is a single-record lookup by ID, contrasting implicitly with the list_employees sibling, and states the required permission. However, it does not explicitly say when to use this versus list_employees or how to discover an ID if unknown.

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