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

Annotations already declare this as a non-read-only, non-destructive, closed-world operation. The description adds real value beyond that: the link expires after 24 hours, the upload is performed by the user, and an upload_id is produced for downstream use. It does not mention authentication or whether links can be revoked, so not a 5.

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 with no filler, and the core action and its 24-hour constraint come first, followed by the hand-off instruction.

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?

With no output schema, the description carries the burden of explaining the return value, and it does identify the upload_id. It does not describe the link format or what the upload experience returns, but the essential contract for a zero-parameter tool is present.

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 has zero parameters, so the baseline is 4. The description correctly frames upload_id as an output to be forwarded to send_letter rather than an input, which prevents confusion.

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 verb and resource ('Erstellt einen Link') plus the object it targets (the user's PDF upload), and names the sibling tool send_letter as the next step. An agent can distinguish it from get_letter_price/get_letter_status/send_letter without opening any schema.

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 tells the agent the scenario (the user uploads the PDF themselves) and the exact follow-up action (pass the upload_id to send_letter). It does not spell out when NOT to use it, e.g. when the caller already has a document, so it falls short of a full 5.

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