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

With readOnlyHint and openWorldHint already declared, the description still adds real value: corpus size (57,000), daily refresh, one-result-per-repository deduplication, and the exact fields returned (GitHub stars, verified domain, version, install/connect command, card). It stops short of explaining ranking, pagination, or what an empty result means.

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?

Single compact paragraph, front-loaded with the verb, resource, and corpus size. The return-field list is a bit of a run-on ('version, install or connect command and a card'), but nothing is padded or redundant.

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?

Without an output schema, the description correctly takes on the job of describing return fields, and it does so. Gaps remain around result ordering, whether the 25-item limit is a hard cap in practice, and how to follow up on a selected server.

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 coverage is 100%, so all four parameters are documented in the schema. The description only marginally extends this — the example query strings illustrate the natural-language style of `query`, and the mention of install vs. connect commands loosely maps to `remote_only`. 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?

Names a specific verb and resource — search the official MCP Registry — and quantifies scope (about 57,000 servers, refreshed daily). This separates it from siblings like find_apis and find_tools by naming an explicit registry, though it never explicitly contrasts itself with those siblings.

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?

Example queries ('query a Postgres database', 'send email', 'Figma designs') implicitly show the intended input style, and the closing line advises reading a server's README and tools before connecting. But there is no explicit when-to-use versus find_tools/find_apis, and no stated exclusions.

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