list_local_users

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

With no annotations, the description carries the burden, and it does add one genuinely useful behavioral fact: passwords are never returned by FortiOS, which tells the agent not to expect credentials. It says nothing about read-only nature beyond "List", permission requirements, pagination, or how vdom scoping affects results.

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?

Front-loaded purpose sentence, then short parameter and return sections with no filler. Mildly redundant with the schema, but the structure is easy to scan and nothing is padding.

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?

No output schema exists, and the description compensates partially by saying the return is "one line per user" and naming the fields shown. For a simple two-parameter list tool that is nearly enough; the only gap is unstated default vdom behavior.

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%, so both parameters are already documented in the schema. The description's restatement ("device_id: Identifier of the FortiGate device", "vdom: Virtual Domain name (optional)") adds no semantics beyond it, 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?

States a specific verb and resource ("List local user accounts defined on the FortiGate") and enumerates the fields returned (status, type, two-factor, email), so the agent knows exactly what entity is being fetched. It does not explicitly distinguish itself from near neighbors like list_admins, list_api_users, or list_user_groups, which keeps it from a 5.

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?

There is no when-to-use guidance, no exclusion of alternatives, and no prerequisites (e.g., whether the device must be reachable or which vdom applies by default). The agent must infer from the name that this is for local user accounts rather than administrators, API users, or user groups.

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