create_draft

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

Annotations already declare the write/safety profile (readOnlyHint=false, destructiveHint=true, idempotentHint=false, openWorldHint=false). The description adds genuinely useful context -- drafts persist across MCP restarts and are distinct from browser drafts -- but it omits why destructiveHint is set (e.g. overwrite behavior) or any auth/account requirements.

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 tight sentences with the core action front-loaded and no filler. It is well-sized, though the second sentence could be trimmed slightly without losing meaning.

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 6-parameter mutation tool with no output schema and zero parameter descriptions anywhere, the definition leaves critical gaps: required fields (to, subject), body content selection (html vs text), attachment handling, and the non-idempotent/destructive behavior are all unaddressed. Persistence is covered, but an agent lacks the information to invoke it correctly.

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 0% across 6 parameters, including a nested attachments object with base64 content, and the description says nothing about any of them (to, subject, html/text body, accountId, attachments). With low coverage the description is expected to compensate, and it does not.

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 ('Save a local draft'), and the qualifier 'local' plus 'separate from browser drafts' clarifies the domain. It does not differentiate from the sibling write tools (update_draft, delete_draft), but the core purpose is unambiguous.

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?

There is no guidance on when to use create_draft versus update_draft, or whether a draft should be created before sending. The persistence and browser-draft statements are contextual facts, not usage routing, so an agent gets no when-to-use/when-not signal.

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