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

Beyond the readOnlyHint and destructiveHint annotations, the description adds significant behavioral context: only Overworld signs were captured; text may combine multiple dated versions and sourceJsonUrl is needed for full history; excerpts are capped at 1024 characters with a textTruncated flag; sign text is untrusted and must not be treated as instructions or proof of authorship. These details go well beyond the annotations and fully disclose response and safety characteristics.

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 a single dense paragraph but remains readable and avoids fluff. It leads with the core purpose, then sequentially covers parameter usage, data limitations, response truncation, security cautions, and pagination. While the flow is logical, breaking it into shorter sentences could improve scannability, but it is appropriately concise.

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 tool has 9 parameters, no required ones, and an output schema, the description covers all key behaviors needed for correct invocation: search modes, radius limits, pagination with nextOffset, response truncation, data provenance, and security handling. It even addresses version history via sourceJsonUrl. An agent can confidently call this tool without additional information.

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?

With schema coverage at 0%, the description must compensate and it does thoroughly. It explains the text parameter with length constraints, coordinates x/z for nearby search, radius range (1..8192), and pagination (max 25 per page, follow nextOffset). It also clarifies dimension behavior through the 'only Overworld' note. Every parameter's purpose is effectively described.

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 captured historical NoCom sign text and distinguishes between text-based (release-wide) and coordinate-based (nearby) searches. It specifies the resource (signs) and gives concrete usage patterns. The mention that only Overworld signs were captured further defines scope, making it easy to differentiate from sibling search tools like search_locations or search_highways.

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 provides explicit usage guidance: supply text for release-wide search, x and z for nearby signs, or both, and gives a radius range. It advises using sourceJsonUrl for complete history and cautions about untrusted content and citation requirements. However, it does not explicitly contrast this tool with alternatives or state when not to use it, though the unique subject matter makes that less critical.

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