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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the agent knows this is a safe read operation. The description adds useful behavioral context: what data is returned (Arabic, transliteration, English/Bengali meanings, customary count) and the default behavior when no phrase is given (returns all six). This goes beyond 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 extremely concise—two short sentences that pack in purpose, input format, optional behavior, and default behavior. Every word earns its place with zero fluff.

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?

For a simple read-only lookup tool with no output schema, the description fully explains what the tool does, what arguments it accepts (via schema plus description), and what it returns. The readOnlyHint and clear usage instructions make it complete for an agent to invoke 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 description coverage is 100% and both parameters ('dhikr' and 'language') already have detailed descriptions. The tool description adds some context by mentioning phrase lookup and language outputs, but it mostly reiterates schema info, so it doesn't significantly exceed the baseline.

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 states the tool's function: looking up dhikr phrases in the Wasilah tasbeeh counter with details like Arabic, transliteration, translations, and count. It distinguishes itself from siblings by specifying a unique resource (tasbeeh counter) and the exact kinds of information returned.

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 explains how to use the tool: provide a phrase for a specific lookup or omit it for all six phrases. It doesn't explicitly mention when not to use it or point to alternatives, but given the sibling tools are clearly different (prayer times, qibla, etc.), the usage context is clear enough.

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