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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world). The description adds the useful coverage fact (all 1,189 chapters, 9 languages) and the return shape (summary with a link to the full commentary). This is solid added context, but does not go deep on auth, rate limits, or fallback behavior when a language is unavailable.

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?

Four short sentences, heavily front-loaded with the core purpose, then content description, then usage trigger, then sibling routing. No filler.

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 read-only lookup with full schema coverage and no output schema, the description is nearly complete: it explains what is returned (a summary plus link) and when to use it. The gap is minor – no note on behavior when the requested language or reference does not resolve.

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 both parameters are fully documented in the schema, including the language enum-ish list and the reference resolution rule. The description's claim of '9 languages' corroborates but does not add syntax beyond the schema. Baseline 3 applies.

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 ('Fetches the Midvash commentary for the chapter a reference points to') and elaborates on what the content contains (context, main movements). Explicitly distinguishes the adjacent sibling by routing text queries to get_passage.

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?

Gives an explicit trigger ('Use this for "what is this chapter about" questions') and names the alternative for text retrieval (get_passage). Clear when-to-use plus when-to-use-something-else.

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