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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is fully covered by structured data. The description adds the useful constraint that retrieval is limited to a same-chapter range of at most five verses and only from "pinned" evidence sources. It says nothing about what happens when the range is invalid or exceeds the chapter, but with annotations this gap is minor.

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?

A single front-loaded sentence with no filler or repetition of the title. It is efficient, though arguably too terse given the five undocumented required parameters.

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?

An output schema exists, so return format need not be described, and annotations cover safety. The remaining gap is parameter documentation: five required parameters with no schema descriptions and only partial coverage in the description leaves an agent guessing at book_id format and range semantics.

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 0%, so the description must carry parameter meaning; it partially does by naming the source enum values implicitly (BSB or WEB) and by revealing that verse_start/verse_end describe a 1-5 verse same-chapter span. It does not explain book_id format (abbreviation? 2-24 chars), chapter/verse numbering conventions, or whether verse_end is inclusive.

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 gives a specific verb ("Retrieve") and resource ("exact, same-chapter verses") plus the qualifying constraints (one to five verses, pinned BSB or WEB). These constraints implicitly separate it from sibling tools like faith_scripture_search_preview or faith_passage_context_preview, though no sibling is named. Clear purpose, but sibling differentiation is only inferable.

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?

There is no explicit when-to-use or when-not-to-use statement, and no alternative tool is named despite nine siblings that overlap heavily (search, compare, context, cross-references). The scope wording ("exact, same-chapter", "one to five") hints at boundaries but never states them as routing criteria.

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