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

The readOnlyHint=true annotation already establishes this is a safe read, so the description's burden is lower. It does add that group and permission-group data come back with each user, but says nothing about volume, pagination expectations, or that results are scoped to the caller's account permissions beyond the terse 'Scope: user'.

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 purpose followed by the scope and endpoint. The raw 'GET /users/.' is near-redundant but cheap, and nothing is padded.

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 simple read-only list tool with a fully documented schema and no output schema, the description covers what the tool returns at a high level (users with groups and permission groups). It stops short of describing the response shape or pagination behavior, which matters somewhat given there is no output schema.

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 schema already documents page, page_size, sort, and the nested filter object with comparisons and examples. The description adds no parameter-level meaning, which is acceptable at full coverage but earns only the 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 and resource ('List users of the Traffit account') and adds the notable payload detail that groups and permission groups are included. The plural 'List users' plus 'Scope: user' distinguishes it from the sibling traffit_get_user, though the contrast is implicit rather than stated.

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?

'Scope: user' hints at the permission context in which the call is valid, and 'List' implies enumeration rather than a single-record fetch. However, no explicit when-to-use guidance or pointer to alternatives like traffit_get_user for a single user is given.

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