send_email

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

With no annotations provided, the description carries the full burden. It discloses important behavioral traits: 'Queues one message per recipient and returns their ids,' indicating asynchronous processing and per-recipient returns. It also states the need to provide a body. It does not cover auth or rate limits, but the key behavior is transparent.

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 description is two sentences with no filler. It front-loads the action and efficiently conveys purpose, key input, and behavioral outcome.

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?

The description provides a solid overview of the tool's purpose, key inputs, and outcome (queued IDs). Given the rich parameter descriptions in the schema, it is reasonably complete for a high-level understanding, though it omits details like error handling or verification requirements for the 'from' field (which are in the schema).

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 adds value by highlighting html_body/text_body as the primary content options and explaining the 'to' array behavior ('one message per recipient'), which enriches understanding of how parameters relate to the tool's behavior.

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 uses a specific verb ('Send') and names the resource ('transactional email through CamelMailer'), clearly stating the tool's action. It also mentions key inputs ('html_body and/or text_body'). However, it does not explicitly contrast with the sibling send_email_with_template, so it lacks explicit sibling differentiation.

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 the usage context (sending emails with raw HTML/plain text) and instructs to provide html_body and/or text_body. However, it does not mention when to prefer this tool over alternatives like send_email_with_template, nor does it state any exclusions or prerequisites.

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