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

The annotations already declare readOnlyHint=true, and the description adds meaningful behavioral detail: results are deduplicated, ranked by a cross-registry trust score, and include install one-liners and links. There is no contradiction, and the behavior is well disclosed for a search-and-list operation.

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?

The description is compact and front-loaded: the core capability and scope appear in the first sentence, followed by usage triggers, return value summary, and parameter details. Every sentence adds useful information without redundancy.

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 readOnly annotation, an output schema, and only three parameters, the description is complete enough. It explains what the tool searches, when to use it, what it returns, and how the optional parameters shape results — an agent can select and call this tool correctly from the description alone.

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 0%, so the description carries the parameter-semantics burden. It compensates well: 'category' is explained with examples, 'limit' is given a 1-10 range, and query semantics are illustrated with concrete search phrases. It does not fully document every nuance, but it provides more than enough for correct invocation.

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 verb and resource: 'Search every major MCP registry at once' and names concrete registries. It clearly distinguishes this tool from the sibling tools, which are about publisher management and integration verification, not discovery.

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 explicit trigger conditions: 'Use whenever you need to FIND an MCP server for a capability' with natural-language examples. It does not explicitly list when-not-to-use alternatives, but the sibling tools are so different in purpose that the usage context is clear.

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