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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is fully covered. The description adds only the "suppression list" framing and says nothing about pagination behavior or what a returned opt-out record contains, so it contributes modest context beyond structured fields.

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?

A single short sentence, front-loaded with the verb and resource, with no filler. It is appropriately sized for a simple read tool, though it borders on under-specified rather than tight.

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 full annotation coverage and a fully documented two-parameter schema, the basics are covered. However, there is no output schema, and the description does not indicate what fields an opt-out entry contains or how pagination terminates, leaving minor gaps.

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 coverage is 100%, and the schema already documents limit (default 25, max 100) and cursor as the next_cursor from the prior page. The description adds nothing about these parameters, which is acceptable given the schema's completeness but is not additive.

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 gives a specific verb and resource ("List opted-out numbers") and adds a clarifying synonym ("the suppression list") so an agent can map it to the right concept. It is distinguishable from siblings like import_opt_outs and set_consent, though it does not name them 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 guidance on when to use this versus related tools such as import_opt_outs, export_consent, or get_consent. The agent must infer that this is the read path for the suppression list from the name alone.

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