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

With no annotations, the description carries the burden and mostly does: it discloses the destructive-ish side effect (code is consumed) and the handoff tool. It omits blocking semantics and what happens on timeout (error vs. silent return), which matter for a wait tool.

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, no filler, with the consumption warning and the follow-up action front-loaded. Every sentence earns its place.

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?

No output schema and no annotations, so the description is the only carrier of behavior; it covers the consumption and the handoff but leaves blocking duration, timeout failure mode, and the site parameter unexplained. Adequate to avoid misuse, but a blocking tool deserves more.

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 only 33%; only identity_id is documented in the schema and the description adds no meaning for site or timeout_seconds. The description does not compensate for the low coverage, so the agent must guess whether site scopes the mailbox and how the timeout bounds the wait.

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?

Specific verb+resource ('Wait until an email code arrives') with the key disambiguator that the code is consumed and not returned, which separates it from retrieval-style siblings like get_email_code. It stops short of explicitly naming the sibling it competes with, so the differentiation is implied rather than stated.

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 routes the agent to the follow-up tool: 'Use fill_email_code to type it into the page.' The consumed-and-not-returned note tells the agent this is not a read path, but it never says when to prefer get_email_code instead or what to do if waiting is inappropriate.

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