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

The description warns that effects 'koennen nicht zurueckgenommen werden' and that side effects are those of the underlying action (which the schema defines as delete | update), yet the annotations declare destructiveHint=false and readOnlyHint=false. An irreversible bulk delete is materially destructive, so the description contradicts the annotation and an agent relying on the hint could delete far more than intended.

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 two operational sentences are compact and front-loaded: purpose, then usage, then the irreversibility warning and prerequisite. The trailing '| EN: object, record, entry, property, link, search' keyword tail is search-engine padding that earns no place for an agent, which keeps this out of the top band.

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 multi-object mutation with 6 parameters and no output schema, the description covers purpose, usage, irreversibility and the narrowing prerequisite, but says nothing about the return shape (per-object success/failure?), partial-failure semantics, batch size limits, or permission requirements. Those gaps matter for a bulk destructive operation.

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 100% — every parameter, including the action=update-only conditionals for name, status, scope_id and external_id, is documented inline. The description adds no syntax, format, or value guidance beyond what the schema already states, so the baseline of 3 applies.

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 with its scope: 'Dieselbe Aktion auf viele Objekte in einem Aufruf anwenden (Massenbearbeitung)'. It implicitly distinguishes itself from the single-object siblings (onto_object_update, onto_object_delete, onto_object_execute_action) by framing itself as the batch alternative to 'einer Schleife aus Einzelaufrufen'.

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?

Gives an explicit trigger ('ab mehreren Datensaetzen statt einer Schleife aus Einzelaufrufen'), names the alternative practice it replaces (looping single calls), and specifies a prerequisite step with a named sibling ('vorher mit onto_object_index die Zielmenge eingrenzen'). Nothing about when to reach for this tool is left to inference.

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