commentary

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

Annotations already declare readOnly/idempotent/non-destructive, so the safety bar is low; the description adds genuinely useful non-obvious behavior: multi-verse notes are filed under the first verse, and entries marked nearest_preceding may apply to the requested verse. It omits that max_chars truncates output, which is the one behavioral gap a caller could trip on.

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-loaded with what the tool returns, then qualifications. The parenthetical author list and the mid-sentence caveats make it slightly dense, but every clause carries information an agent would otherwise have to guess.

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?

There is no output schema, so the description rightly explains that results are quoted with citations, and the module/filing semantics are covered. Missing are the ref format and the truncation behavior of max_chars, which matter for a tool that silently caps output at 3000 characters.

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 compensate and only partly does: it explains modules (names from commentary_modules) and hints at ref semantics via nearest_preceding, but says nothing about the ref string format or the max_chars budget (default 3000) and what happens on overflow.

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 outcome: it returns what named public-domain commentaries say on a passage, quoted with citations. Naming the authors (Matthew Henry, JFB, Barnes, Clarke, Keil and Delitzsch, Calvin, Robertson) concretely bounds the resource and separates it from siblings like church_fathers and dictionary, though it never explicitly contrasts with them.

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?

Implies the trigger clearly (you want verse-level exegetical commentary on a passage) and points to commentary_modules as the source of valid module names, which is real routing guidance. It stops short of stating when to prefer church_fathers or translation_notes instead.

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