gmail_send

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

With no annotations, description carries full burden. It states the email is sent immediately and warns that in_reply_to_message_id must be RFC822 Message-Id, not Gmail id. Discloses important behavioral detail about reply threading. Could also mention that sending is irreversible.

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 sentences, no wasted words. First sentence gives main action, second adds crucial reply context. Front-loaded and efficient.

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?

Given 9 parameters, 0% schema coverage, no output schema, and no annotations, the description partially addresses the complexity. It covers key parameters for sending and replying but omits cc, bcc, html, and output behavior. Could be more complete.

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%, so description must add meaning. It explains account, to, subject, body (implicitly), and gives detailed semantics for thread_id and in_reply_to_message_id. However, it does not cover cc, bcc, or html parameters, leaving gaps.

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?

Clearly states 'Send an email immediately from the given account.' This provides a specific verb and resource, and distinguishes from siblings like gmail_draft_create or gmail_draft_send by emphasizing immediate 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?

Explicitly explains how to use the tool for replies, including needed parameters thread_id and in_reply_to_message_id. It implies usage for new emails without these. No explicit when-not-to-use, but clear enough for the agent.

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