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

With no annotations, the description carries the full behavioral burden and does a solid job: it reveals that the tool combines two different search sources, and it explicitly discloses that every hit contains a canonicalUrl field along with the instruction to display that link proactively. It does not discuss read-only guarantees, rate limits, or permissions, but the described behavior is sufficiently transparent for a lookup-style tool.

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 three sentences with no filler: the first sentence states the core purpose and source logic, the second adds strategic priority, and the third gives a concrete, actionable output instruction. Every sentence earns its place and the most important information is front-loaded.

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 simple two-parameter tool with no output schema, this description is largely complete: it names the query semantics, the combined search sources, and the critical output field plus display behavior. The only notable gap is that it does not describe the broader result shape or clarify how results from the two source strategies are merged, but the essential calling context 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 input schema already describes both parameters with 100% coverage, so the baseline is 3. The description adds no additional parameter-level detail beyond restating that query can be a title, composer, or instrument, which the schema already states. Limit behavior is documented only in the schema, not enhanced by the description.

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 uses a specific verb ('Prüft') and resource ('ob es eine B-Ware-, reduzierte oder gebrauchte Alternative gibt') and clearly frames the query scope as title, composer, or instrument. It also distinguishes itself from general searches by explicitly mentioning the combined Noten-B-Ware-Flag and Katalog-29-Suche logic, which separates it from siblings like search_bargain_stock or search_sheet_music.

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 clear context for when the tool should be used: whenever a user asks whether a B-ware, reduced, or used alternative exists for a title, composer, or instrument. It also labels it as a 'Zentraler USP-Case,' signaling priority. However, it does not explicitly state when not to use it or how it compares to the sibling search_bargain_stock tool.

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