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

Annotations already declare readOnlyHint=true and destructiveHint=false, but the description adds material behavior: inline retention of 30 days for batches up to 1,000 emails, a 5-day temporary download_file link, the caution to share it only with the account owner, and the fact that replies may be truncated below the requested limit.

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?

The purpose is front-loaded and the dense single paragraph carries almost no filler; retention windows and the sharing caution are high-value. It is long and packs multiple concerns (pagination, download link, cost) into one block, which slightly hurts scanability.

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 carries the full burden and does so: it names the response sections, the conditional inline emails array with its retention, the download_file fallback, and the pagination cursor. An agent can call this and interpret the response without further documentation.

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%, so the baseline is 3; the description still adds meaning by explaining that the returned page may hold fewer results than limit and how to continue via emails_page.next_offset, and by linking download_file to larger batches. It does not elaborate on partial or include_emails beyond what the schema already says.

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 (batch status/results) and explicitly ties it to the producing sibling emailable_create_batch, so it is distinguishable from create_batch at a glance. It even enumerates the returned fields (message, progress, reason_counts, total_counts), removing ambiguity about what 'batch' means here.

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?

It tells the agent how to consume results: paginate with emails_page.next_offset, and use download_file for large batches. It also notes the call is free, which is a practical selection signal. It does not state when NOT to use this over emailable_get_account or emailable_verify_email, so it falls short of explicit exclusions.

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