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

No annotations are provided, so the description carries the behavioral burden. It discloses the out-of-band nature (the person opens the address themselves), the security-sensitive instruction to never accept passwords, and the requirement to pass through the address/code unchanged. It does not explicitly state side effects such as whether repeated calls invalidate prior codes, but it covers the most critical behaviors well.

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 compact and front-loaded: the first sentence states the core action, the second states the output, the third gives the user workflow, and the last gives critical guardrails and next steps. Every sentence adds necessary operational information without fluff or repetition of the title.

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 zero-parameter tool with no annotations, the description covers the purpose, the user-side flow, the security constraint, the exact output format expectations, and the follow-up tool to use. The sibling list and output schema would handle the remaining details, so nothing critical is missing for selecting and invoking this tool.

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 tool takes zero parameters, so the schema has no parameter semantics to explain. The description nevertheless explains what the tool returns (address and verification code), giving the agent the semantic meaning of the operation even without input parameters to describe. This fully compensates for the absence of parameters.

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 verb ('startet eine Anmeldung'), names the resource ('Shop'), and clearly distinguishes this from sibling login-status/order tools. It explains the output (address and verification code) and the WordPress login flow, making the tool's function 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 gives explicit when-to-use guidance by noting that after starting login the agent must check via 'get_login_status', and it explicitly tells the agent what not to do ('Frag NIE nach einem Passwort'). It also tells the agent how to present the result, which guides usage beyond just selecting the tool.

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