send_email

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

Annotations already declare readOnly=false and destructiveHint=true; the description adds actionable behavioral constraints: the WRAPS_WRITE_ENABLED prerequisite and the verified SES identity/region requirement. This enriches the safety and operational picture without contradicting the annotations.

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-load the core action, then state requirements and recipient flexibility. Every sentence earns its place, no repetition or filler.

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 tool has an output schema, so return values are covered elsewhere. The description covers the essential prerequisites (env var, verified identity) and the key constraining rule (to accepts array). It could mention body requirements but those are in the schema. Overall complete for an agent to invoke correctly.

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 each parameter is already documented. The description restates the to field's array capability and the from identity requirement, but adds no new meaning beyond the schema—meeting the baseline for high coverage without additional value.

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 opens with 'Send a transactional email via your AWS SES account,' naming a specific verb, resource, and channel type. It immediately distinguishes this from sibling tools, which are all inspection or setup operations (get_setup_status, list_recent_sends, etc.), so an agent can tell exactly what this tool does.

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 provides clear usage context: it is for sending transactional email, requires WRAPS_WRITE_ENABLED=true, and the from address must be verified. While it doesn't explicitly contrast with alternatives, none of the sibling tools are send operations, so the context is sufficient without exclusions.

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