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

The annotations already declare readOnlyHint=true and destructiveHint=false, so the description doesn't need to re-explain safety. It adds meaningful behavioral context beyond annotations: the tool renders no widget, is internal/preparatory, ignores diacritics and punctuation, and treats numeric-only queries as ordinal matches. These are non-obvious behaviors that help the agent understand what this tool actually does at runtime.

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 front-loaded with the most critical information ('INTERNAL/preparatory tool — text-only, no widget rendered') and every sentence serves a purpose: usage restrictions, chaining context, anti-pattern warning, and query constraints. It is dense but not bloated, and the structure guides the agent through decision-making efficiently.

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 simplicity (2 parameters, full schema coverage, no output schema, annotations present), the description covers all necessary context: when to use, when not to use, specific query behavior, and what to do with results (chain). It leaves no critical gaps for an agent to invoke the tool incorrectly, making it complete for its complexity.

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% because both query and max_results have descriptive text in the schema. The description's main body adds no new parameter semantics; it only echoes the Arabic-script and numeric-ordinal behavior already present in the query parameter description. Thus, the description adds no value beyond the schema, warranting the baseline score.

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 specifies the tool's purpose: 'search the Quran by Arabic text' and is explicitly tagged as 'INTERNAL/preparatory tool — text-only, no widget rendered.' It distinguishes itself from the sibling tool ayah_search by positioning itself as the data-only variant for raw results or chaining, making its purpose unambiguous from the start.

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 when-to-use guidance: ONLY when the user asks for plain text/no widget, or when chaining into other tools (play_ayahs, ayah_tafsir, ayah_translation) in the same turn. It also gives a clear when-not-to-use: never as the user-facing answer, and 'Do not follow ayah_search with this tool — that is duplicated work.' It names the preferred alternative ayah_search and even says 'When in doubt, prefer ayah_search.'

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