gmail_draft

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

With no annotations, the description carries the full burden and does well on the most important trait: it never sends, and a human must review and send. It also explains the threading effect of reply_to_uid. It omits return behavior (e.g., draft id), permission/auth requirements, and whether duplicate drafts are created on repeat calls.

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?

Three short sentences, front-loaded with the action and its most important constraint (never sends), with no filler or redundancy. Every sentence contributes information an agent needs.

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 five-parameter mutation tool with no annotations and no output schema, the description covers the critical behavior (no send, human review, threading) but leaves gaps: it doesn't describe what is returned after creating the draft, how missing cc is handled, or any permission requirements. Adequate but not fully self-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 coverage is 80%, so the schema already documents to, body, subject, and reply_to_uid, with only cc undocumented in both places. The description's note that reply_to_uid turns the draft into a reply in that message's thread adds real meaning beyond the schema's bare "uid of the message this replies to," but it is a small increment over an already well-covered schema.

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 ("Create a draft in Gmail") and immediately clarifies the crucial constraint that it never sends. It does not explicitly distinguish itself from sibling tools like gmail_search or gmail_read, but the operation is unambiguous enough that an agent won't confuse it with the read-only siblings.

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?

Usage is only implied: "A person reviews and sends it" suggests this is the right tool when human review is desired rather than immediate delivery. There is no explicit when-to-use/when-not-to-use guidance and no mention of alternatives, so the agent must infer the selection criteria.

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