resend_emails

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered; the description still adds real behavioral value by disclosing result ordering ('newest first') and the cursor-paging mechanism. It says nothing about when the listing ends, whether there is a max limit, or what happens with an invalid cursor.

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 sentences, zero filler, with the core purpose and the paging instruction both front-loaded. Every clause carries information the agent 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?

An output schema exists, so return values need not be described, and the pagination story is partially told. Still missing are termination behavior at the end of the list and any guidance on the limit parameter, which matter for a cursor-paged listing tool with 0% schema coverage.

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%, so both parameters are undocumented in the schema and the description must compensate. It explains 'after' well by tying it to the next_after value from the previous page, but 'limit' is never mentioned, leaving half the parameter surface unaddressed.

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 sent emails') and clarifies ordering ('newest first'), which importantly disambiguates the tool from its name, which reads like a re-send action. It never explicitly contrasts with the sibling resend_send, so the agent must infer the split between listing and sending.

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?

The description implies usage (read a list of sent emails, page through it) and gives concrete paging mechanics, but offers no when-to-use/when-not guidance and no routing hint relative to resend_send or resend_domains. Adequate but inference-dependent.

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