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

The description discloses rich behavioral traits beyond the readOnlyHint annotation: exact word matching, umlaut/accent folding ('fuhrt' matches 'führt'), phrase search, trailing-star prefix search, and optional book restriction. This gives the agent a thorough understanding of how the search behaves.

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?

Four sentences, each earning its place: purpose, syntax rules, use-case, and scope restriction. Information is front-loaded and free of redundancy. The structure flows naturally from what the tool does to how to use it.

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's complexity (full-text search with syntax and translation options), the description covers key aspects: search semantics, use case, and book restriction. Output schema covers return values. A minor gap is the lack of mention of limit behavior or exclusions for sibling tools, but the description is largely complete.

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%, giving the baseline 3. The description adds significant meaning: query syntax examples (e.g., 'Hirte mangeln', '"Gnade um Gnade"'), wildcard semantics, and translation edition details including aliases and instance availability. This enriches parameter understanding beyond the schema.

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 opens with 'Full-text search over the German Bible text', a specific verb and resource that clearly defines the tool's function. It further details search features (exact word forms, phrases, prefix wildcard) which distinguishes it from sibling tools like bible_lookup or bible_compare.

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?

Explicit guidance is given: 'Use this to locate a passage when the wording is known but the reference is not.' This states the intended scenario clearly, but it does not mention alternative tools or exclusions, so it falls short of a full comparison with siblings.

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