Sammelbelege

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered structurally. The description adds one genuinely useful domain fact — a single document may bundle multiple invoices — but says nothing about ordering, whether all property documents are returned by default, or how the documents relate to record_invoice. With annotations present, a 3 is appropriate.

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?

A single, front-loaded sentence with no filler; the parenthetical naming the concept ('Sammelbelege') earns its place. It is efficient but so terse that it borders on under-specification rather than tightness.

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 read-only list tool with one optional filter, plus a full schema, annotations, and an output schema, the description covers what the resource is. The main residual gap is sibling disambiguation from list_invoices, which is only implied.

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 100% and the single optional property_id parameter is already documented in German ('nur Belege dieser Immobilie'). The description adds no further semantics about the parameter, so the baseline of 3 applies — the schema does all the work.

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 identifies the resource — uploaded documents that can contain several invoices (Sammelbelege) — but never states the verb or that it returns a list; that has to be inferred from the tool name. It hints at the distinction from single-invoice tools via 'können mehrere Rechnungen enthalten', yet does not explicitly contrast itself with the sibling list_invoices.

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?

There is no guidance on when to call this rather than list_invoices, and no mention of what to do with the returned documents (e.g. pass to record_invoice). The only usage signal is the implicit 'these are the multi-invoice ones'.

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