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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description still adds real value by disclosing the matching semantics (same as the website search box) and the exact return shape — titles, one-line summaries, canonical URLs, capped at 10.

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 short sentences, front-loaded with what is searched, then how matching works, then what comes back. Nothing is redundant or padded.

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?

No output schema exists, yet the description compensates by spelling out the return fields and the result cap. For a two-parameter read-only search this is nearly complete; only the empty-result or no-match behavior is left unstated.

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% and the description adds nothing beyond it for query or limit; the "at most 10" cap merely restates the schema's maximum. With the schema already documenting both parameters and giving a query example, the baseline 3 applies.

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?

"Search PlainError's published plain-English error fixes" gives a specific verb and resource, and the verb alone distinguishes it from get_fix and explain_error. It stops short of naming the siblings explicitly, so the differentiation is implied rather than stated.

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 implies discovery-style lookup ("uses the same matching as the website search box"), which suggests free-text/keyword queries, but it never says when to use this instead of get_fix or explain_error. The agent has to infer the routing rule from the verbs.

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