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

Annotations already declare readOnlyHint=true and openWorldHint=false, covering safety. The description adds behavioral nuance beyond annotations: the membership matching rule ('knight' matches 'knights') and the fact that filters are stat-based. No contradiction with 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 sentences, front-loaded with the purpose and a clarifying example. Every clause earns its place, and the membership nuance is integrated naturally without bloat.

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 filter-based search tool with 13 optional parameters, an output schema, and read-only annotations, the description covers the primary use case and key behavior. It doesn't explain pagination (cursor/limit) or the include_inactive flag, but these are secondary to the core query pattern. Adequate for an agent to invoke it correctly in most scenarios.

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 only 31%, and the description mentions 'attack, defense, armor and required level' but doesn't explain the min/max variants or that these are range filters. The example implies required_level_max, but many parameters (sort, limit, cursor, include_inactive) are left unexplained. It adds some meaning beyond the schema but does not fully compensate for the low coverage.

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 ('Find'), resource ('Tibia items'), and scope ('matching class, type and stat filters'). The example query clarifies the exact kind of question it answers, distinguishing it from sibling tools like tibia_search (likely broader) and tibia_find_creatures (creatures, not items).

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 concrete use case ('which two-handed swords need level 100 or less') and a membership nuance for vocation/weapon type. It doesn't explicitly state when not to use it or contrast with alternatives, but the example strongly implies the appropriate context.

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