Lookup Rule

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

With no annotations, the description carries the full burden and does reasonably well: it declares 'Read-only', enumerates the returned payload (citations, effective dates, plain-language summary, corpus version, as-of date, disclaimer), and adds the important caveat that this is legal information, not legal advice. It stops short of disclosing auth/permission requirements or any rate/scope limits.

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 sentences, purpose front-loaded in the first line, the output shape and the legal caveat following in order of decreasing importance. No sentence is filler; even 'Read-only.' earns its place since no annotations are supplied.

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 simple three-parameter read tool with full schema coverage and an output schema, the description covers purpose, mutability, payload contents, and the legal disclaimer. The one remaining gap is usage scoping (when this tool is the right choice, and what the corpus covers), which would be low-cost to add.

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 the schema already explains state format, topic examples, and the as_of omission semantics ('rules not yet effective on that date are omitted'). The description adds no parameter-level detail beyond that, so the 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?

The description states a specific verb and resource with a precise domain: 'Look up the employment-law rule card(s) for a state and topic.' That is far more specific than a generic 'lookup' and tells an agent exactly what comes back. There are no sibling tools, so the sibling-differentiation clause cannot be satisfied, which keeps it just short of a 5.

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?

Usage is only implied: an agent can infer it should call this when it needs employment-law rules for a given state and topic, and the required state/topic parameters reinforce that. There is no explicit when-to-use, when-not-to-use, or alternative tool to route to, and no mention of the scope of the corpus (e.g. non-US jurisdictions).

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