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

Annotations carry only a title, so the description bears the behavioral burden; it does disclose that the operation is a read and that omitting the argument returns the whole collection. It says nothing about response shape, collection size, pagination, or what happens with an out-of-range book number, which matter for a whole-collection read.

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?

Two tight sentences with no padding, and the scope statement leads. The exclusion sentence is short but its benefits would be larger if it named the correct alternative tool.

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 one-optional-parameter read with no output schema and no behavioral annotations, the description identifies the source and the argument semantics but leaves return format and the relationship to the four islam_*/prayer_* siblings unstated. Minimum viable rather than 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% and the schema already explains that book is a book number and should be omitted for the collection. The description restates the same optionality without adding format, range, or validation detail, so baseline 3 is appropriate.

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 and resource: read the Sahih al-Bukhari collection, with an optional book selection. The closing clarification that it is not a hadith-number lookup meaningfully narrows the purpose, though it does not distinguish this from near siblings such as islam_read or prayer_saying.

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?

Provides a negative rule ("not a lookup by hadith number"), which implies an alternative exists but never names it, so the agent must infer that islam_search or islam_read is the right route for numbered lookups. No explicit when-to-use context is given for the bare no-argument call.

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