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

Annotations already cover the safety profile (readOnlyHint=true, openWorldHint=true). The description adds useful context that the returned ids serve as foreign keys elsewhere, but says nothing about pagination behavior, return size, or permissions beyond what the schema already declares.

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 what is returned before the usage note. No filler, though the phrasing 'Use an id as user_id or owner of...' is slightly terse and grammatically compressed.

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 two-param read-only list tool with full schema coverage and annotations, the essentials are present. The remaining gap is routing guidance against bexio_get_current_user and any note on what the list covers (active vs. all users).

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 100% and both params (limit, offset) are fully documented in the schema, including the next_offset hint. The description adds no parameter detail, 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 (list) and resource (company's bexio users) and names the returned fields (id, name, email). It distinguishes itself from bexio_get_current_user by scope ('the company's' users vs. current user), though that distinction requires inference from the sibling name.

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?

The second sentence gives a downstream purpose for the returned ids ('Use an id as user_id or owner of contacts, documents and timesheets'), which implies when to fetch them. But it never explicitly says when to use this versus bexio_get_current_user, and there are no exclusions.

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