register_or_login

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

No annotations are provided, so the description carries the full burden. It discloses only that a user_id is returned; it does not say whether a new account is created on first use, how the role default is applied, or what happens on invalid/expired codes. For a combined register-or-login mutation, this leaves the key behavioral question (does calling it create a user?) unanswered.

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 short sentences, front-loaded with the purpose before the return value, with no wasted words. It is terse rather than bloated, though the terseness is part of why other dimensions suffer.

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?

An output schema exists, so the return format need not be explained, but the description still omits the role parameter's meaning, the send_verification_code prerequisite, and any account-creation behavior. For a tool with an undocumented optional parameter and no annotations, this is under-specified.

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% and the description compensates only partially, implying email and code via '邮箱验证码'. The optional role parameter with its default of 'candidate' is never mentioned, so an agent has no signal about when or why to set it. With three parameters and no schema-level documentation, this is a significant gap.

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 states a specific action pair on a specific resource: register or log in using an email verification code. An agent can distinguish it from generic auth tools, though it does not explicitly differentiate itself from the sibling send_verification_code, which is clearly its prerequisite.

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?

No guidance on when to use this versus alternatives. The sibling send_verification_code exists and is evidently required to obtain the code this tool consumes, but the description never mentions that dependency or any precondition. Usage must be inferred entirely from the name.

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