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

Annotations already declare read-only, idempotent, closed-world, non-destructive behaviour. Beyond that, the description explains the excerpt-by-default behavior, the full=true escalation, and that shared names surface as a candidate list — non-obvious result-shape facts the annotations do not cover.

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: what is read and from where, when to use it, then what comes back and how to expand it. The return-shape note is front-loaded immediately after usage rather than buried, with no filler wording.

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?

A two-parameter read tool with full schema coverage, an output schema, and complete annotations needs little more. The description covers purpose, trigger questions, and the one meaningful output-size decision (excerpt vs full), leaving no gap an agent must guess at before calling it.

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 100%, so both parameters are already documented, including the boolean default and the examples for name. The description restates the full/excerpt trade-off and adds the candidate-selection nuance for name, but adds no syntax or format detail 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?

Uses a specific verb and resource: read dictionary/encyclopedia entries from named sources (Easton's, Smith's, Nave's) about a person, place, object, custom, or subject. That scope is distinguishable from siblings like lookup_word (word definitions) or get_theme, so an agent can route correctly without opening the schema.

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 usage cue — background/history questions or the 'who or what was X in the Bible' phrasing — which is exactly the intent an agent needs. It stops short of naming an alternative tool to prefer for linguistic or passage-based questions, so sibling disambiguation is implied rather than stated.

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