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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds that results are 'indexed results' and tied to Deep Research mode, which is useful but does not disclose limitations like pagination or relevance behavior.

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 two short sentences with no filler. The main scope is front-loaded, and the second sentence adds meaningful behavioral context about the return mode.

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 one-parameter read-only search tool, the description covers the entity scope and the output mode adequately. The lack of an output schema leaves the exact result shape underspecified, but this is a minor gap for a search 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% for the single query parameter, so the schema already documents it. The description adds the cross-entity scope but does not explain the query syntax or expected format beyond what the schema provides.

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 names a specific action, 'Search,' and a clear resource scope: 'across trips, items, and locations.' This distinguishes it from sibling tools like fetch and trip_* list operations, and the mention of 'Deep Research mode' further clarifies its specialized role.

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 makes the primary use case explicit: searching across multiple entity types and retrieving indexed results for Deep Research mode. It does not explicitly state when to prefer fetch or trip_* alternatives, but the scope is clear enough to guide selection.

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