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

Beyond the readOnlyHint annotation, it reveals the semantic nature of the search and instructs the agent to 'answer FROM the returned chunks and cite rule numbers', which is important behavioral context. No contradictions.

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, no fluff; the first sentence states purpose, the second provides usage and parameter guidance.

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?

The description is complete for a search tool: purpose, usage, param guidance, and output expectation are covered. The limit parameter is not addressed, but output schema likely covers it.

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 descriptions are absent, but the description explains the kinds parameter with specific values and their intended use cases, providing meaningful guidance. Query and limit are left to schema/defaults, which is acceptable for obvious params.

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 states a specific action ('Semantic search') over a specific resource ('Magic Comprehensive Rules, glossary, and 84k card-specific rulings'), which clearly distinguishes it from siblings like get_rule or get_card_rulings.

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 explicitly says 'Use for any rules/interaction question' and provides filter guidance for kinds ('ruling' vs 'rule'/'glossary'). However, it does not explicitly state when not to use it or mention alternative tools.

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