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

With no annotations, the description carries the full burden. It usefully discloses the sending address and that composition is deterministic, but says nothing about the fact that sending is an irreversible side effect, required permissions, or failure behavior. Schema covers body/attachment constraints, so the gap is behavioral rather than structural.

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?

A single front-loaded sentence with zero filler; the verb and the distinguishing constraint ('deterministic; no LLM draft') both land immediately.

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?

For a send tool with no annotations and no output schema, the description is thinner than ideal: it does not address irreversibility, auth/permission requirements, or what success looks like. The richly documented 7-parameter schema compensates for most structural needs, leaving only these behavioral gaps.

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% across all 7 parameters, including the html/text/subject relationship and attachment limits, so the schema does the heavy lifting. The description adds no parameter-level meaning beyond the schema, which matches the baseline 3.

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?

States a specific verb (Send), resource (outbound email), and scope (from the user's @nova.civai.co address), and adds 'deterministic; no LLM draft' which implicitly separates it from the sibling 'converse'. It stops short of naming the alternative sibling explicitly, so it is clear but not maximally differentiated.

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 phrase 'no LLM draft' hints at when this tool is appropriate versus a draft-generating sibling, but there is no explicit when-to-use/when-not guidance, no mention of prerequisites, and no routing instruction. Usage is implied rather than stated.

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