draft_create

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

With no annotations, the description carries the full burden, and it does so reasonably: it discloses that nothing is dispatched, that the storage backend (IMAP/EWS/Graph) is auto-selected from configuration, and that a feature flag must be enabled. It omits details like error/permission behavior, but the safety-critical non-send fact is stated.

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 tightly written sentences, front-loaded with the action and immediately followed by the safety-critical caveat and the activation prerequisite. No filler.

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 and all 11 parameters are documented, so return-value explanation is not needed. The description covers the operation, its side-effect boundary, and the enablement gate; only finer operational detail (e.g., failure modes) is absent, which is minor here.

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% with 11 well-documented parameters (including required 'to'/'subject' ranges and an attachment sub-schema), so the schema already does the heavy lifting. The description adds no parameter-level detail, matching the baseline for full schema coverage.

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 new email as a draft in the account's Drafts folder') and immediately scopes it against the send operation with 'Nothing is sent.' An agent can distinguish it from siblings like draft_send and draft_update without opening any schema.

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?

'Nothing is sent' clearly demarcates this from draft_send, and 'Save a new email' implies creation rather than draft_update. The prerequisite 'Requires MAIL_DRAFTS_ENABLED=true' is a genuine usage gate. It stops short of naming sibling tools explicitly, so it doesn't reach the top bar.

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