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

Annotations already establish read-only, open-world, idempotent, and non-destructive behavior. The description adds useful context beyond that: it returns passages with author attribution and canonical URLs, and it may include separately labelled historical fiction. This helps set expectations for open-world results without contradicting the 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 long but front-loaded with the core function and usage guidance before the optional fiction caveat. The extended topic list is somewhat verbose, but it serves a clear disambiguation purpose for a broad search tool and every sentence contributes useful information.

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 output schema exists, parameter descriptions are complete, and annotations cover safety and open-world behavior, the description fills remaining gaps: it defines the search scope, return format, attribution, and the optional historical-fiction behavior. An agent can reasonably decide when and how to invoke this tool without missing critical 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?

Schema description coverage is 100%, with both query and limit already well documented in the input schema. The tool description reinforces the query's purpose by listing example search subjects, but it does not add new parameter-level meaning beyond what the schema already provides, so a baseline score of 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 states a specific verb ('Search') and a precise resource (Spencer Hofmans' published historical research and companion guides), then enumerates the covered topics. It clearly distinguishes itself from siblings like get_historical_figure or get_guide by framing this as a broad search tool rather than a targeted retriever.

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 explicit guidance on when to use the tool: 'Use this for questions about...' followed by a thorough list of applicable subjects. It does not explicitly name alternative sibling tools or state when not to use it, but the use context is clear enough for an agent to select it correctly.

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