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

Annotations already declare readOnly, idempotent, non-destructive, so safety carries less burden. The description adds useful behavior beyond them: what comes back ('projects with their views (pages) and highlighted snippets') and that matching is full-text over titles/content. Pagination behavior is left to the schema.

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?

Three short sentences, front-loaded with the operation and result shape before the routing hint. Every sentence earns its place with no filler.

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 an output schema present, return-value details need not be spelled out, and the description still adds the snippet/view context. Pagination defaults and limits live in the schema, so what remains for the description is complete enough to call correctly.

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% and fully documents page, size, and text (including the contrast with xtiles_list_projects). The description adds nothing parameter-specific beyond the general notion of a free-text query, so the baseline 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 ('Full-text search across projects') and even describes the result shape ('matching projects with their views (pages) and highlighted snippets'). It does not explicitly name the sibling it should be used instead of (xtiles_list_projects appears only in the schema's text param), so sibling differentiation is left implicit.

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?

'Use this when the user references a project by name or topic rather than ID' gives a clear triggering condition. It stops short of naming the concrete alternative (xtiles_list_projects) or stating exclusions, so it is clear context rather than a full when/when-not map.

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