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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile needs no restating. The description adds one genuinely non-obvious fact — that the returned id is the default user_id for new records — but says nothing about failure modes, auth requirements, or what happens if the session has no 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 compact sentences with zero filler: the first establishes what is returned, the second immediately delivers the operational implication of the id. Nothing could be removed without losing 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?

With no parameters and no output schema, the description carries the burden of describing the response, and it does so by listing the fields. The main residual gap is that it doesn't state that the call is a single-object read rather than a list, though 'the signed-in user' makes that clear enough in practice.

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?

The tool takes no parameters, so the baseline is 4. The description's field list (id, name, email, flags) is return-value information rather than parameter guidance, which is the right thing to spend words on for a zero-arg tool.

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 names a specific resource and scope — the signed-in user — and enumerates the returned attributes (id, name, email, superadmin/accountant flags), which implicitly separates it from bexio_list_users. It stops short of naming the sibling explicitly, so the differentiation is inferable 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?

Usage is implied by 'Its id is the default user_id of new records' — an agent can infer this is the tool to call before creating records that need an owner. There is no explicit when-to-use/when-not framing and no reference to the bexio_list_users alternative.

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