delete_draft

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

The description complements the annotations (destructiveHint: true, idempotentHint: true) by detailing the specific behavioral trait that a draft already sending or sent cannot be deleted, and clarifies that the action is irreversible in terms of enabling future sending. There is no contradiction with annotations.

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 three sentences with zero wasted words. Each sentence serves a distinct purpose: stating the core action and effect, providing when-to-use scenarios, and giving an important constraint. It is front-loaded with the key verb and resource.

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 tool with a single documented parameter, clear annotations, and no output schema, the description is fully complete. It explains the tool's action, valid usage scenarios, a critical restriction, and does not need to describe return values since none are required.

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?

The sole parameter 'id' is fully described in the schema (format, pattern, source). The description adds usage context (the draft must be in a deletable state), but since schema coverage is already 100% with a good description, the baseline is high. Score 4 because the description adds useful behavioral context beyond the schema's type/format info.

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 states the verb ('discard') and the resource ('a draft by its id'), clearly differentiates the outcome ('so it will never be sent'), and distinguishes it from the 'send_draft' or 'reply_email' siblings by specifying that the tool is for withdrawal before sending.

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 explicitly states when to call this tool ('a staged or pending-approval message should be withdrawn — e.g. it is no longer needed or was created by mistake') and provides clear exclusion criteria ('A draft that is already sending or sent cannot be deleted'), guiding the agent away from inappropriate use.

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