send_email

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

With no annotations provided, the description carries full burden for behavioral disclosure. 'Send an email directly' implies a write operation that transmits an email, but it doesn't disclose critical traits: whether this requires specific permissions, if emails are sent immediately or queued, rate limits, error handling, or what happens on success/failure. The description is too minimal for a mutation tool with zero annotation coverage.

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 extremely concise with just three words, front-loaded with the core action. There's zero wasted language, making it easy to parse quickly, though this conciseness comes at the cost of completeness.

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 this is a mutation tool (sending emails) with no annotations and no output schema, the description is incomplete. It doesn't explain what the tool returns, error conditions, or behavioral nuances. For a 6-parameter tool that performs a potentially destructive action, more context is needed to guide safe and effective usage.

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 the schema fully documents all 6 parameters (to, subject, body, html, cc, bcc) with clear descriptions. The tool description adds no parameter information beyond what's in the schema, so it meets the baseline of 3 where the schema does the heavy lifting.

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 'Send an email directly' clearly states the action (send) and resource (email), but it's vague about scope and lacks differentiation from siblings like 'create_draft' or 'update_draft'. It doesn't specify if this sends immediately versus scheduling, which would help distinguish it from draft-related tools.

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 no guidance on when to use this tool versus alternatives. It doesn't mention when to choose 'send_email' over 'create_draft' for composing emails, or when to use it in conjunction with 'list_emails' or 'search_emails'. There's no context about prerequisites like authentication or email client setup.

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