Send Email

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

Discloses immediate sending, irreversibility, recipient validation, deduplication, 500 recipient limit, and confirmation requirement. Annotations do not contradict; destructiveHint=false is consistent as sending is not data destruction. Rich behavioral details.

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?

Well-structured with warning, details, args, returns. Front-loaded with critical info. Slightly verbose (e.g., 'Addresses are validated...' could be part of param description), but still efficient and clear.

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?

Given 7 parameters, output schema exists, and no nested objects, the description covers purpose, behavior, all parameters, return values (by referencing status), and errors (ValidationError). No 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 0%, but description adds full meaning for all 7 parameters, including types, purpose, constraints (validation, dedup, limit), and the critical confirm parameter. Compensates excellently for missing schema descriptions.

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?

Clearly states 'Send an email to recipients' with immediate sending and irreversibility. Differentiates from siblings like email_create_draft by emphasizing sending vs drafting. Specific verb and resource.

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?

Explicitly requires user confirmation and warns of immediate irreversible action. Context is clear for sending, but no direct mention of when not to use (e.g., for draft use email_create_draft). Still strong guidance.

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