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

Annotations only declare readOnlyHint=true, so the description adds real value: it discloses the two search modes, the language routing (Arabic for Qur'an/hadith, English for Tanakh), and the return shape ({source: id, quote}). It omits any mention of the limit/cap behavior or result volume.

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?

A single dense sentence with the core action front-loaded and examples batching the detail efficiently. Nothing is wasted, though the parenthetical language hints could be tightened.

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?

It compensates for the missing output schema by describing the returned id shape, and covers intended usage, but with three undocumented parameters and an undocumented cap, the description is only adequately complete for a search tool.

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 0%, so the description carries the burden. It meaningfully distinguishes reference lookup from word lookup (mapping loosely to ref and q) but never names the parameters and never mentions 'limit' or its maximum of 20, leaving one parameter entirely unexplained.

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?

States a specific verb ('Find') and resource ('passages to cite') and gives concrete examples of the two lookup modes, so the agent knows what the tool produces. It does not explicitly differentiate itself from the sibling get_passage, which the agent must infer.

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 phrase 'passages to cite' implies the retrieval use case, and 'by reference or by words' hints at when each input mode applies. There is no explicit when-not guidance or named alternative (e.g., get_passage for a known passage), leaving routing to inference.

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