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

Annotations already declare readOnlyHint=true, openWorldHint=true and destructiveHint=false, so safety is covered. The description adds value by listing what the response contains (subscription list, state, attribution, timestamp), but says nothing about pagination, ordering, or auth requirements.

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 elements, the resource summary front-loaded followed by the endpoint path. No wasted sentences, though the phrasing 'The list subscriptions of one contact' is slightly awkward.

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?

A simple single-parameter read-only getter with annotations covering the safety profile and a description covering the return shape; nothing an agent critically needs is missing. Pagination/ordering details would be the only marginal addition.

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 0%, but there is only one required parameter and the description supplies its identity via the GET /contacts/{contactId}/subscriptions path. It adds no format, constraint, or sourcing guidance beyond what the schema type already conveys.

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 (get/list) and resource (subscriptions of one contact), and even enumerates returned fields (list, subscribed/suppressed state, who added it and when). This distinguishes it from siblings such as sendlane_get_contact_tags and sendlane_get_contact_custom_fields, though it does not name those alternatives explicitly.

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?

There is no when-to-use guidance, no condition for choosing this over sendlane_get_contact or the other per-contact getters, and no prerequisites stated. Usage is only implied by the resource name.

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