draft_send

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

With no annotations, the description carries the full burden, and it discloses the key behavioral facts: the operation mutates state and destroys the draft ('remove it from Drafts'), and it requires MAIL_DRAFTS_ENABLED=true and MAIL_SMTP_WRITE_ENABLED=true. It does not state irreversibility or failure behavior, but the side effect and config gating are the most important facts an agent needs.

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?

Two short sentences, zero filler, with the primary action stated first and the prerequisites following. Every clause 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?

An output schema exists, so return values need not be explained, and the description covers the action, its destructive side effect, and the required feature flags. What remains thin is routing relative to the many send-capable siblings, but for this simple two-parameter tool the definition is close to sufficient.

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% for both parameters, so the schema already documents draft_id and account_id. The description adds no syntax, format, or default semantics beyond what the schema provides, which is the baseline 3 case.

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 and resource ('Send an existing draft') plus the resulting side effect ('remove it from Drafts'), so it is clearly distinct from draft_create, draft_update, and draft_delete. It does not explicitly name or contrast with smtp_send_message, which sends a new message, so the sibling differentiation is implied rather than stated.

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 'existing draft' implies the applicability condition (a draft must already exist), and the two feature-flag prerequisites give real context for when the call will succeed. However, there is no explicit guidance on when to prefer this over smtp_send_message or graph_send_message, and no when-not guidance.

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