send-email

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

Annotations already indicate destructive behavior (destructiveHint=true). The description adds value by disclosing rate limits and recipient allowlist nuances, which are not captured in structured fields. It also explains the dry-run mode's non-destructive behavior.

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 extremely concise with only two sentences. The first sentence states the primary action, and the second adds critical usage hints. No unnecessary words, front-loaded for quick comprehension.

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 9 parameters and destructive side effects, the description is adequate but lacks information about the return value (e.g., success message or ID) and error handling for rate limits or invalid recipients. It covers the main usage but not the full context.

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 100% with detailed parameter descriptions. The description does not add new semantics for parameters besides mentioning dryRun and global constraints. Baseline 3 is appropriate as the schema fully covers parameter meaning.

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 clearly states 'Compose and send an email' with a specific verb-resource pair. It distinguishes itself from siblings like 'draft' by mentioning sending with an optional dry-run mode. The 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?

The description provides some usage guidance by highlighting 'dryRun=true to preview without sending' and mentions rate limits and allowlist constraints. However, it does not explicitly contrast with sibling tools like 'draft' or 'read-email', leaving the decision to the agent.

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