send_email

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

The description lacks disclosure of side effects (e.g., sending is a write operation) or other behaviors like authentication, rate limits, or delivery guarantees. Since no annotations are present, the description carries full burden but fails to inform beyond the obvious.

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 minimal (one sentence), which is concise but not well-structured. It lacks front-loading of key information and does not earn its brevity by covering essential details.

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?

With no output schema, the description does not explain return values or error states. For a tool with 5 parameters and no nested objects, more context about the sending process (e.g., confirmation, async) would improve completeness.

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 clear parameter descriptions. The tool description adds no additional meaning beyond what is already in the schema, so the baseline score 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 'Send a new email' clearly identifies the action (send) and resource (email), distinguishing it from siblings like list_emails, modify_email, and search_emails. However, 'new' adds minor value; overall it is clear but not exceptionally specific.

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?

No guidance is provided on when to use this tool versus alternatives such as modify_email (which might handle drafts or edits). There is no mention of prerequisites, limitations, or when not to use it.

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