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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so safety is covered. The description still adds real behavioral detail those annotations cannot convey: per-language truncation at roughly 3000 characters for a single ref and 1500 for multi-ref reads, with an explicit [TRUNCATED] marker in the output.

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?

Three tight sentences: capability first, range syntax second, truncation limits last. Every clause carries information an agent would otherwise have to discover by trial, and nothing is repeated from the schema.

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 two-parameter read tool with no output schema, the description covers the input modes, the batching limit, the accepted ref syntax, and the one surprising return behavior (truncation). An agent can call it correctly and interpret the response without further guessing.

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%, so the two parameters are already documented, including the max-10 limit on refs and that it substitutes for ref. The description adds value on top by showing that a range form such as 'Shabbat 21b:5-11' is accepted, which the schema's examples do not demonstrate.

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: returns full Hebrew and English text of one canonical ref or up to 10 refs, with links. The scope (canonical refs, bilingual text) separates it conceptually from fetch_commentary, though no sibling is named explicitly.

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 implies when to use it (you already have a canonical ref) and gives a practical constraint of up to 10 refs. It never states the when-not case or points to resolve_ref for normalizing a non-canonical reference or to semantic_search when the ref is unknown, so routing is left to inference.

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