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

Annotations already declare readOnlyHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds non-obvious behavior: the search scope is limited to *visible* calendars, multiple words are ANDed, and the result contains only id (slug), title and link. It omits result limits/pagination and ordering, which keeps it below 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 dense sentences with no filler: search scope and matching rule first, return shape and next-step tools second. Nothing is repeated from the schema or annotations.

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 correctly takes on the burden of describing the return value (id as slug, title, link) and even names the follow-up tools for drill-down. What is missing is pagination/result-count behavior and a disambiguation from find_calendars, the closest sibling.

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 query parameter is already documented with examples, so the baseline is 3. The description nonetheless adds genuine meaning the schema does not convey: the terms are matched across five specific fields and all terms must be present, which materially changes how an agent should construct the query.

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 (full-text search) and resource (visible Advent calendars) and enumerates the searched fields (Name, Marke, Kurztext, Merkmale, Interessen), which is well beyond a title restatement. It is not fully differentiated, however: the sibling find_calendars is never mentioned, leaving ambiguity about when to pick search versus that tool.

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 a real usage rule ('alle Wörter müssen vorkommen', i.e. AND semantics) and explicitly routes the agent to get_calendar or fetch for details, which is a clear alternative. It lacks any negative guidance about when not to use this tool, and does not position it relative to find_calendars or similar_calendars.

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