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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint false. The description adds meaningful behavioral context beyond these: it federates specific registries, uses live use counts from Smithery, dedupes results, and ranks remote Streamable HTTP servers first. It does not contradict 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?

The description is compact and front-loaded: a clear action sentence, followed by concrete behavioral specifics, then a usage directive. Every sentence adds value and there is no filler.

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 read-only search tool with no output schema, the description is quite complete: it names the data sources, ranking behavior, returned fields, and when to use it. It could be slightly stronger by directing the agent to mcp_details for follow-up on a specific server, but nothing essential is missing.

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 all four parameters with defaults, constraints, and purpose. The description adds only an example of capability phrasing, not parameter-level semantics; baseline 3 is appropriate.

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 opens with a specific verb and resource: 'Search for existing MCP servers that provide a capability,' with concrete examples. It further distinguishes the tool by describing federation across MCP Registry, Smithery, and npm, deduplication, and remote-first ranking, making its discovery role unambiguous relative to the sibling mcp_details.

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 an explicit usage trigger: 'Use before building or asking the user to build a tool.' It does not explicitly discuss when not to use it or mention mcp_details as the alternative for follow-up detail, but the stated use case is clear enough for an agent to select it appropriately.

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