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

Annotations already declare readOnly/idempotent/non-destructive, but the description goes well beyond them: it discloses the per-row provenance block, the nullable effective-date behavior and why it can be null, the AND-combination semantics of filters, the three-character minimum that causes a query to be refused, and the meaning of an empty result. It also warns that the tool does not read service records, which is exactly the kind of limit an agent needs.

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?

The usage trigger is front-loaded and the paragraph is dense rather than padded, but it is a single long block with several clauses about provenance blocks and date nullability that could be tightened. Nothing is truly wasted, though the row-format detail is heavy for the space it occupies.

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 no output schema, the description carries the return-value burden and does so thoroughly — listing the fields per row, the provenance repetition, and the nullable date semantics. Combined with the input constraints and empty-result interpretation, an agent has everything needed to call and interpret this tool correctly.

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 100%, so baseline would be 3, but the schema declares required: [] while the description states the real constraint that at least one of condition/serviceEra/exposureType is required — a genuine gap-fill. It further adds filter interaction semantics and the word-length validation rule, plus the interpretive nuance about condition descriptions stating a limit of the presumption.

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 opens with a specific verb+resource scoped to a well-defined domain ('whether VA treats a condition as presumptively service connected, or which conditions are presumptive for a given exposure or service era'), and it enumerates the return contents. It never names a sibling tool or states what it is not, so an agent must infer its boundary against search_legal_authority or find_secondary_conditions on its own.

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?

'Use this when a veteran asks whether...' gives an explicit triggering scenario, and the requirement that at least one of condition/serviceEra/exposureType be supplied is a usable precondition. There is no when-not guidance and no named alternative for adjacent questions (e.g., general legal authority lookups).

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