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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered without the description. The description adds only the mild disclosure that per-recipient status is included; it says nothing about pagination behavior, ordering, or how many recipients a batch may contain, which matters for a list endpoint.

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 front-loaded sentence with no filler, but it is arguably over-trimmed: the space saved could have carried a 'use X to do Y' clause that the agent actually needs.

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?

With no output schema, the description at least indicates what a row contains (recipient + status), and limit/cursor are covered by the schema. But for a paginated list tool in a large batch-oriented sibling set, missing pagination guidance, the meaning of the status filter, and differentiation from get_batch_results leaves clear 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 75%, so the schema documents id, limit (default 25, max 100) and cursor; the baseline is therefore 3. The description adds no parameter meaning, and the undocumented 'status' parameter is ambiguous — it could be a filter, yet the description's 'each one's status' phrase suggests status is returned rather than filtered on.

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 a batch's recipients) plus a return-content hint ('with each one's status'), so an agent knows exactly what it retrieves. It does not, however, distinguish itself from nearby siblings like get_batch_results, get_batch, or list_batches, which an agent must infer from names alone.

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 statement of when to use this instead of get_batch_results or list_batches, nor any prerequisite such as the batch needing to exist or be in a terminal state. Usage must be inferred entirely from the name.

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