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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful behavioral context that annotations cannot convey — that this is one of three complementary content sources whose output is intentionally partial. It does not say what a missing/empty section looks like, which keeps it below a 5.

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 short sentences with the core action front-loaded and the section list immediately after. The final sentence slightly restates the preceding one ('None is sufficient alone' follows the pairing advice), which is mild redundancy rather than noise.

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 four-required-parameter lookup with no output schema, the description establishes the content source and cross-tool relationship but says nothing about return shape, empty/missing sections, or why chapter and verse take no descriptive guidance. Adequate to select the tool, thin on what to expect from a call.

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 only 25% — only 'book' is documented, while chapter and verse are bare integers with no format, range, or validation guidance. The description repeats the section enum verbatim without explaining what any section contains, so it does not compensate for the coverage gap.

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 ('Fetch a section of the curated in-house commentary for a verse') and enumerates the seven section values, so the agent knows exactly what granularity of content is returned. It also explicitly positions itself against siblings by naming get_matthew_henry and get_church_fathers.

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 explicit when-to-use routing: it names the two peer commentary tools to pair with and warns that none is sufficient alone. The exclusion ('do not treat this as "the" source') tells the agent precisely what not to do with the result.

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