defender_get_machines

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds concrete OData filter examples (healthStatus, riskScore, startswith on computerDnsName), which gives agents actionable knowledge beyond the annotations. It doesn't contradict annotations.

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?

The description is a single concise line followed by three illustrative examples. It's front-loaded with the verb and resource, every word earns its keep, and the example filter expressions are tightly relevant. No unnecessary elaboration.

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?

Given no output schema, the description could mention that it returns a list of machine objects, but 'List devices' implies that. The combination of description and schema covers what it lists, how to filter, and paging via top/skip. A note on return shape would be a minor addition, not a critical gap.

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 each parameter (top, sKip, filter) is already well-documented. The description adds value by showing exact syntax for the filter parameter, which helps an agent construct valid queries rather than just knowing the schema type. This goes beyond 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 devices onboarded to Defender for Endpoint'. The OData filter examples clarify it's the general machines list, not a filtered-by-vulnerability or software list. It doesn't explicitly distinguish from sibling tools like defender_get_machine_by_id, but the naming and verb 'List' make the core purpose clear.

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?

It implies use when you need a list of machines with OData filtering, and provides realistic filter examples, but it doesn't state when not to use it or mention alternatives such as defender_get_machines_by_vulnerability or defender_find_machines_by_tag. There is no explicit exclusion or routing guidance for the sibling set.

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