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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world. The description adds meaningful context beyond that: the data source and licence (OpenBible.info, CC BY), that ranking reflects human reader votes and is 'a human judgement, labelled as such', the 12-result cap with strongest first, and that passages are read verbatim from stored KJV text. No contradiction with annotations.

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?

Front-loads what the tool returns before moving to usage and limits. Most sentences earn their place, though the parenthetical source/licence attribution is dense and could be trimmed without loss.

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?

With an output schema present, the description needn't explain return values, and it still covers origin, ranking basis, result cap, and a caveat that linked verses are human judgement. Nothing needed to invoke the tool correctly is missing.

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 67%, with reference and include_text already documented in the schema. The description adds semantics the schema lacks, namely that the limit is capped at 12 and ordered 'strongest first', clarifying what the ranking and truncation mean for the result set.

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+resource: the passages most often linked to a verse by readers, sourced from OpenBible.info and ranked by reader votes. The phrase 'Scripture interprets Scripture: use it to follow a thread through the Bible' makes it distinguishable from siblings like scripture_search, verses_for, and what_the_bible_says_about without any schema inspection.

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 clear usage context ('follow a thread through the Bible') and three example user phrasings ('verses related to Romans 8:28', 'cross references for John 3:16') that map intent to tool. It does not, however, explicitly exclude or name competing siblings such as verses_for or scripture_context, so guidance is clear but not fully routed.

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