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

With no annotations, the description carries the full behavioral burden. It does disclose the return shape at a high level (single storyboard vs. index) and a notable interpretive constraint ('a reference point, NEVER an identity assignment'), but says nothing about access/permissions, result size, pagination, or the format of the 'verified refs'.

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?

Purpose and scope lead, and every clause is operational: the parenthetical examples ground 'narratives', and the id/movement/default rule is stated directly. Nothing is repeated or decorative.

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 two-parameter lookup with no output schema, the description covers selection semantics and the interpretive framing, but leaves the movement vocabulary unenumerated and the response structure (ref format, volume) unspecified. An agent could invoke it, but would be guessing at valid movement values and result shape.

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 0%, so the description must compensate — and it does: it explains that id selects one storyboard, movement fans a single theme across all storyboards, and omitting both yields the index, plus a concrete example value ('testing'). It fails to enumerate the 17 movement values, which is the one thing an agent most needs for that opaque string parameter.

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 identifies the resource (storyboards / biblical narrative patterns with verified refs) but never supplies a clean verb — it is not stated as 'return', 'list', or 'browse'. The retrieval behavior has to be inferred from the invocation sentence ('Pass id for one storyboard; else the index'), and the theological framing occupies more space than the operational statement of purpose.

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?

Explicit conditional usage is given: pass id for one storyboard, pass movement='testing' to walk a movement across every storyboard, otherwise the index is returned. It also states a framing constraint on how to interpret results. It stops short of naming any alternative sibling (e.g. harmony, canon, characters_browse) for related lookups.

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