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

Annotations already declare readOnlyHint=true, so the description's job is to add scope, and it does: it discloses the exact fields returned and that entries are account-scoped ('in your Operto account'). It omits pagination/result-size behavior, which is the main remaining unknown for a list endpoint with no parameters.

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 front-loaded sentences: what it returns, then why it matters as a first call, with the endpoint appended as a compact reference. No filler or redundancy.

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 output schema, the description must convey the return shape, and it enumerates the key fields plus the id's downstream utility, which is sufficient to call the tool correctly. Pagination or result-size limits are the only meaningful omission for a parameterless list.

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 zero parameters, so there is nothing for the description to disambiguate and the baseline of 4 applies. Schema coverage is 100% and empty, consistent with the description's framing as a parameterless account-wide listing.

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 the properties (units)'), names the fields returned (Operto id, partner_id, name, subscription state), and gives the underlying endpoint. The 'list' vs 'get' distinction from operto_get_property is clear without needing to open either schema.

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?

'Good first call: the ids feed the other tools' explicitly tells the agent when to reach for this tool and why. It stops short of naming an alternative or a when-not-to-use condition (e.g. use operto_get_property for a single unit's detail), so it is a clear context statement rather than a full routing rule.

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