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

Annotations only declare readOnlyHint=true; the description carries the rest and adds real value by enumerating the data each agent record returns (online status, last seen, OS, hardware, logged-in user) and mapping to the two concrete REST endpoints. It still omits rate limits, result-size/pagination behaviour and whether hardware detail is expensive to fetch.

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?

Three short sentences, front-loaded with what the tool returns before the optional filter and the underlying endpoint. Every sentence carries information; nothing is padded or repeated from the title.

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 read-only list tool with no output schema, the description covers the returned fields, the optional customer scoping and the API route, which is enough for an agent to call it correctly. It stops short of describing result-set size or how to page through a large estate, which matters given a 900-tenant installation.

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 page, items_in_page and customer_id are already documented with bounds and defaults. The description's 'Pass customer_id to list only one customer's devices' merely restates the schema's 'Only this customer's agents,' adding no new syntax or semantics — the 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?

The description pairs a precise verb (List) with the resource (Atera agents) and even defines the domain term — 'the managed machines' — then enumerates the returned attributes. It clearly reads as the bulk-listing tool, but it never names the neighbouring single-agent tools (atera_get_agent, atera_find_agents_by_machine), so differentiation is inferred 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?

'Pass customer_id to list only one customer's devices' gives parameter-level usage, not tool-selection guidance. There is no statement of when to prefer this over atera_find_agents_by_machine or atera_get_agent, and no guidance on pagination strategy for large tenants.

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