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

Annotations already declare destructiveHint=true, idempotentHint=true and readOnlyHint=false, so the safety profile is carried structurally. The description adds a genuinely new fact not in any structured field: contacts are not affected by the deletion. It stops short of saying whether the deletion is permanent or what happens to automations/schedules referencing the segment.

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, zero filler, with the destructive action stated first and the notable side-effect caveat immediately after. Nothing to trim.

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 single-parameter delete, the combination of a destructive/idempotent annotation set, a fully described id, and the contacts-not-affected note covers what an agent needs to invoke it. Missing only whether deletion is reversible and whether dependent automations break.

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?

There is one parameter and schema coverage is 100% ('Segment id'), so the schema fully documents it. The description adds no format, prefix, or lookup guidance beyond that, making the 3 baseline appropriate.

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?

Specific verb + resource: 'Delete a segment.' The second sentence preempts a likely misreading (that contacts in the segment are removed), which sharpens the scope. It does not explicitly contrast with update_segment or get_segment, but the resource distinction is unambiguous against the delete_* siblings.

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?

No indication of when to use this versus update_segment or list_segments, and no prerequisites or confirmation guidance. The only cue is the implicit 'you need the segment id', which the schema already supplies.

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