send_email

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

Annotations already mark destructiveHint=true, confirming the immediate send. The description adds context about failure conditions (PROTONMAIL_ALLOW_SEND false, Bridge unreachable) and confirms it returns delivery confirmation. No contradictions.

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 concise, front-loaded with purpose and alternatives, no extraneous words. Every sentence adds value.

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 14 parameters well-described in schema, annotations present, and no output schema, the description covers behavioral aspects, failure conditions, and return value adequately. Minor gap: does not specify response format beyond 'delivery confirmation', but 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 coverage is 100% with good parameter descriptions. The description does not add extra meaning beyond the schema; baseline of 3 is appropriate.

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 clearly states the tool composes and sends a new outbound email via Proton Bridge SMTP, specifying it's for one-shot messages that need no review. It distinguishes itself from create_draft and reply_to_email, which are sibling tools with different purposes.

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 states when to use (one-shot messages with no review needed) and when not to (prefer create_draft for review, reply_to_email for replies). Also mentions failure conditions: if PROTONMAIL_ALLOW_SEND is false or Bridge SMTP unreachable.

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