send_email

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

With no annotations, the description carries the full burden of behavioral disclosure. It states that the tool sends an email, but does not disclose side effects, delivery semantics, authentication requirements, whether sending is immediate, or what response to expect. This is minimal coverage for an action with real external effects.

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 a single front-loaded sentence with no filler. 'Send a new email' immediately states the action and object, and the attachment qualifier is the only extra detail. It is concise without being under-specified in structure, though other dimensions capture the lack of depth.

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?

This is a 7-parameter tool with a nested attachments object, no output schema, and no annotations. The description does not explain return values, required permissions, or when to prefer this over reply_to_email. The schema covers fields well, but the description leaves important operational context missing.

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 parameters are already well documented in the schema. The description only adds 'optional attachments,' which duplicates existing schema information rather than adding new semantic meaning. The baseline of 3 is appropriate because the schema carries the weight.

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 uses a specific verb and resource: 'Send a new email with optional attachments.' This clearly identifies the action and distinguishes it from sibling tools like reply_to_email, since it explicitly says 'new email.' It gives the agent enough to know what the tool does at a glance.

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 about when to use this tool versus alternatives such as reply_to_email or draft-related operations. There is no mention of context, prerequisites, or exclusions, so the agent must infer usage from the tool name alone.

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