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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds meaningful context beyond that: the exact field set that gets matched, skill matching behavior, and the fact that it takes no title_id. It does not cover result count limits or pagination, so not 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?

Four sentences with the core purpose front-loaded and no filler. The field list is long but earns its place by explaining what 'keyword search' actually matches, which is the non-obvious part of this tool.

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 single-parameter search tool with full schema coverage and no output schema, the definition covers purpose, matching scope, and usage examples adequately. It is slightly light on return-shape expectations (no output schema exists), but this is a minor gap.

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% (baseline 3), and the description adds the important AND semantics implicitly via its field list and the phrase about matching. The schema itself states 'every word must match', so the description's added value is the field enumeration rather than a syntax detail it omits.

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 (keyword search) and resources (modules and skills), and explicitly distinguishes itself from name-based lookup by naming the fields matched (id, name, type, engine, genre, summary, etc.). An agent can tell this apart from get_module, list_modules, and get_skill without opening any schema.

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 clear usage signal: find a ready module by feature ('dice board', 'idle income') rather than by name, and notes skills match on name/description. However, it does not explicitly name the alternative tools (list_modules, list_skills, get_module) or exclusion conditions.

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