send-email

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

No annotations are provided, so the description carries the full burden. It discloses that the tool sends an email (destructive action) and labels it a 'CONFIRMATION STEP', implying it should only be called after user confirmation. However, it does not mention side effects (e.g., irreversible), required permissions, or error behavior. It provides minimal behavioral context beyond the action itself.

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 concise sentences with no waste. The first sentence front-loads the core purpose and usage guideline, making it immediately actionable. Every word earns its place.

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 there is no output schema and no annotations, the description provides minimal context. It covers the action and preconditions but omits return value (e.g., success confirmation), error handling, and irreversibility. For a send operation with 4 parameters, it is adequate but not comprehensive.

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% (all 4 parameters described in schema), so the baseline is 3. The description adds: 'Required fields: recipients (to), subject, and content. Optional: CC recipients.' This maps 'recipients' to the 'to' parameter but does not add new meaning beyond the schema's existing descriptions (e.g., 'List of recipient email addresses (confirmed)'). Thus, it barely enriches parameter semantics.

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's purpose: 'Actually send the email after user confirms the details.' It uses a specific verb+resource (send email) and distinguishes from siblings by emphasizing it is a confirmation step. No other sibling tool sends an email, so differentiation is inherent.

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 explicitly states a precondition: 'Before calling this, first show the email details to the user for confirmation.' It also lists required and optional fields. However, it does not mention when not to use the tool or provide alternatives, but given the sibling list, no alternatives exist, so the guidance is clear.

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