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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so the safety profile is covered. The description adds a genuinely useful operational trait — the <= ~2KB budget — that no annotation conveys. It still doesn't say how ambiguous or failed matches behave, which keeps it short of a 5.

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 with the trigger condition front-loaded, then the constraint, then the sequencing against siblings. Every clause carries information; nothing is padding.

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?

An output schema exists, so return values need not be explained, and the annotations carry the safety profile. The description covers trigger, ordering relative to siblings, and a budget. It is only slightly thin on what happens when a reference resolves to multiple or zero laws, which matters for a resolver.

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 both parameters are already documented and the baseline is 3. The description adds meaning beyond the schema by framing 'reference' as possibly partial/fuzzy rather than an exact citation, which is important call semantics; the 'region' hint is left entirely to the schema.

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 the input (citation, title, or partial reference) and the exact output (one canonical law_id), which is a specific, checkable purpose. It implicitly resolves against get_law_context and read_law, so an agent can place it without opening schemas. It loses a point only because the verb is implied rather than stated directly.

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?

It gives an explicit precondition ('WHEN you have a citation, title, or partial reference'), names the alternatives and the ordering ('Use this before get_law_context or read_law when the law is named'), and adds a budget. Nothing about when-to-use is left to inference.

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