List segment subscriber IDs

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered structurally. The description adds genuinely useful context beyond that by naming the required OAuth scope (segments:read) and noting it reads account data, but it says nothing about pagination traversal or the scope of the read beyond the single 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?

Three short sentences, front-loaded with the action and followed by the two facts an agent needs (data access and auth scope). No filler or redundancy.

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 endpoint with a fully documented schema and no output schema, the description is adequate but leaves two gaps: how results are paged back and how this differs from get_segment_subscribers. The name's 'expand_results' phrasing also hints at behavior the description never explains.

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 all five parameters (page, limit, account, segment_id, publication_id) are already documented with ranges and ID patterns. The description adds no parameter-level meaning, so the baseline of 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?

States a specific verb and resource ('List segment subscriber IDs') and makes clear the payload is IDs rather than full subscriber objects. However, it does nothing to distinguish itself from the sibling get_segment_subscribers, which an agent would reasonably consider for the same task.

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 when-to-use guidance and no mention of alternatives. With get_segment_subscribers present in the sibling list, the absence of any routing hint leaves the agent to guess which of the two tools to invoke.

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