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

Annotations already declare readOnlyHint=false, destructiveHint=false and idempotentHint=false, so the description's job is to add context — and it does: an invitation email is dispatched to the employee, and the creation cannot be undone through this server. It does not address duplicate-email/code behavior or required permissions, which matter for a 14-required-param mutation.

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?

Four compact sentences, front-loaded with the WRITE marker and the core action, then prerequisites and constraints. The endpoint string is the only arguably expendable element and it costs nothing.

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 17-parameter, 14-required mutation with no output schema, the description covers the essentials: side effect (email invite), irreversibility, prerequisite lookups, and the two-part-name constraint. It omits what the call returns (employee id?) and how duplicates are handled, which leaves a small but real gap.

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 88%, so the schema already documents each field including the 'jisr_list_lookup' provenance for the four id parameters. The description restates that lookup dependency rather than adding new meaning, and says nothing about the optional contract_end_date / outsourcing_company_id interactions. Baseline 3 is appropriate.

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?

Opens with an explicit verb and resource ('WRITE: register a new employee in Jisr'), and the parenthetical clarifies the mechanism (invitation by email). It is unmistakably distinct from the read/list siblings and from jisr_create_attendance_punches.

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 a concrete prerequisite workflow: 'Get department_id, employment_type_id, location_id and nationality_id from jisr_list_lookup first.' It also rules out an expectation ('no delete tool'), which shapes how cautiously the agent should act. It stops short of stating when NOT to use this tool (e.g., employee already exists), so not a full 5.

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