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

Annotations already establish readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral context beyond annotations: the default compact summary shape, the effect of detail='full', and that the search covers both stock content and user house rules.

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 sentences with no fluff: purpose and scope come first, followed by the key output-shape behavior. Every sentence earns its place and the most decision-relevant 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?

Given the rich output schema, full parameter documentation, and complete annotation set, the description covers all essential context: scope, searchable content, query dimensions, and response behavior. Pagination and sort syntax are already handled in the schema, so nothing important is missing.

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%, so the baseline is 3, but the description adds meaning for the detail parameter by specifying what summary returns (identification + summary + categories + publisher/source) and what full returns (complete documents with embedded sub-document arrays). This goes beyond the schema's brief enum descriptions.

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 verb and resource: searching the rules library the user has access to, including stock content and house rules. It enumerates the rule types covered and the query axes (name, type, ruleset), making it easy to distinguish from sibling vault search tools like vault_search_characters or vault_search_spells.

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 states when to use the tool: to locate any of the listed rule categories by name, type, or ruleset. It provides clear context about the library scope, though it does not explicitly point to alternatives such as vault_get_rule or mention when not to use this tool.

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