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

With no annotations, the description carries full behavioral disclosure. It mentions the registry is deduped, quality-scored, refreshed every 30 minutes, free, returns up to 25 results, and lists returned fields (score, status, remotes, packages). This exceeds minimal expectations.

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?

Three sentences, all substantive and front-loaded with the core action. Each clause adds value: defining scope, return details, and alternative tool. No redundancy or 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?

The description covers purpose, limitations, return content, maintenance characteristics, and the paid alternative. For a simple search tool with fully documented schema and no output schema, this is complete and self-sufficient.

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 cover both parameters 100%, including constraints (limit 1-25, default 10) and query semantics (case-insensitive substring, omit for top servers). The description adds no extra parameter information, so 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 clearly states the tool searches the MCP server registry by name/title/description, using a specific verb and resource. It also distinguishes this tool from the sibling get_mcp_registry_snapshot by noting that the snapshot returns the full corpus.

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?

It explicitly specifies when to use this search tool versus an alternative: 'For the FULL corpus (~1500 servers) use get_mcp_registry_snapshot (paid, x402).' It also notes the free nature, result limit, and that omitting the query returns top servers by quality score.

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