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

Annotations already declare the full safety profile (readOnly, idempotent, non-destructive, closed-world), and an output schema exists, so the description's job is to add domain context. It does so by defining the 'house item' subset relative to the broader vault catalog and by explaining the leg/ruleset scoping model, which is real behavioral context beyond the annotations.

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 tightly packed sentences with the core purpose front-loaded and the filtering behavior following. Every clause carries meaning, though the ruleset guidance is somewhat duplicated from the schema, which costs a point.

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 only two parameters, rich annotations, and an output schema, the definition covers what an agent needs: the subset semantics, the leg model, and the filter behavior. Nothing essential is missing, though it could have routed the agent away from the broader vault catalog search tools.

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%, so the schema already documents both parameters. The description's ruleset sentence largely restates the schema's own description of that parameter rather than adding new syntax or edge-case meaning, 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 ('List the campaign's house items') and clarifies the domain term by defining house items as 'the items it holds as active house-rule associations', which separates it from vault_search_items and play_list_campaign_rules. It does not explicitly name the adjacent sibling tools, so it falls just short of full sibling differentiation.

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 guidance on how to use the optional ruleset filter (omit for all legs, set to scope to one leg), which is genuinely useful usage context. However, it offers no when-to-use comparison against alternatives such as vault_search_items or play_list_campaign_rules; usage is implied rather than routed.

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