send_account_email

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

With no annotations, the description carries full behavioral burden and does so thoroughly: it discloses the real-world effect of sending a message, concurrency limits, 410 vs 404 semantics, and the email_sent=false retry signal. This goes far beyond a basic action statement and prepares the agent for non-obvious outcomes.

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 longer than average, but every sentence earns its place: core purpose first, then rationale, user-confirmation requirement, channel exceptions, and edge-case response semantics. Front-loading the essential action and the 'do not call automatically' warning makes it highly usable despite the length.

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?

Even with no output schema, the description covers all critical operational aspects: when a call is valid, what a 410 means, what a 404 means, how to handle delivery failure, and the one-session-one-email invariant. For a sensitive send action, this is complete enough for an agent to act 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?

The schema already fully describes the single parameter, so the baseline is 3. The description adds meaningful context by specifying that the id must come from an email-channel account-bootstrap session, which refines what value is valid even though it does not introduce new parameter syntax.

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 action ('Deliver the verification email') and a specific resource ('account-bootstrap session created with channel email'), and explicitly distinguishes itself from create_account, which sends nothing. This makes it immediately clear what the tool does and how it differs from its most relevant sibling.

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?

Gives explicit when-to-use guidance: only for email-channel sessions, only after user confirmation, and never automatically after create_account. It also explains when not to use it for other channels and how to interpret repeat-call results, leaving no ambiguity about invocation conditions.

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