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

Annotations already declare readOnlyHint=true, openWorldHint=true and destructiveHint=false, so safety is covered. The description adds genuinely valuable behavioral context beyond that: bank details and NI number are never returned, and it names the underlying GET /employees/{id} endpoint, which helps an agent understand the data boundary.

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?

One tight sentence with the return-content detail and exclusion front-loaded, followed by the endpoint. Zero filler; every clause carries 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?

There is no output schema, so the description usefully compensates by sketching the returned fields and explicitly excluding sensitive ones (bank details, NI number). It is close to complete for a simple single-record read, though it omits error behavior for invalid/unknown ids.

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 there is only one parameter, so the schema already documents employee_id. The description restates 'by id' but adds no format, range, or lookup guidance beyond what the schema provides, making 3 the correct baseline.

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+resource: fetch one employee's record by id. It enumerates the returned content (personal/job details, contacts, manager, working pattern) and the id-based scope, which cleanly distinguishes it from breathehr_list_employees.

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?

'by id' implies the single-record use case versus the sibling list tool, and the never-returned fields give a hint about appropriate use. However, it never explicitly says when to choose this over breathehr_list_employees or breathehr_list_employee_jobs, so the routing is left to inference.

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