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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds behavioral context beyond annotations by mentioning 'interactive display' and 'all matches,' which clarifies the output/display style 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 exactly two sentences, front-loaded with the main purpose and then immediately providing usage conditions. Every word earns its place; no filler or redundancy.

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 low complexity (3 params, no required) and the presence of an output schema, the description sufficiently covers the core use cases and constraints. It explains how to invoke via phrase_text or phrase_id and notes the source of a phrase_id, making it complete for an agent to decide and call correctly.

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 descriptions already cover all three parameters at 100% coverage, including the mutually exclusive relationship between phrase_id and phrase_text. The description adds practical semantics by explaining when to use each parameter (e.g., phrase_id from ayah_mutashabihat), which enriches the schema's baseline information.

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 a specific verb and resource: 'Show phrase mutashabihat occurrences with an interactive display.' This clearly distinguishes the tool from siblings like ayah_mutashabihat (which deals with ayahs) and search_ayahs_text (text search), by focusing specifically on phrase-level mutashabihat occurrences.

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 explicitly states 'Use this when:' followed by two concrete scenarios: user provides phrase text asking where it appears, or user has a phrase_id (e.g., from ayah_mutashabihat) wanting all matches. This clearly guides when to invoke this tool over alternatives, even though no exclusions are stated.

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