compose_email

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

Discloses key behaviors: mode options (send/draft/open), body_html fallback requirement, attachments as file paths, and from_address constraints. Lacks error handling or rate limit info, but given no annotations, this is adequate.

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?

Description is long but well-structured with bullet-style parameter explanations. The purpose is front-loaded. Some redundancy could be trimmed, but the length is justified by 10 parameters.

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?

Covers all parameters and basic return value, but lacks context on when to prefer sibling tools like create_rich_email_draft or prerequisites like account configuration. With output schema present, return details are acceptable.

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 has 0% description coverage, but the description adds extensive meaning: examples for account, comma-separated for recipients, plain-text fallback, mode descriptions, file paths for attachments, and from_address must be configured.

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 'Compose and send a new email from a specific account.' This distinguishes it from sibling tools like forward_email or reply_to_email.

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?

Provides no explicit guidance on when to use this tool versus alternatives such as create_rich_email_draft or manage_drafts. The mode parameter implies different uses but no direct comparisons.

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