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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description usefully signals that only metadata plus a source URL is returned (full text lives elsewhere), but it says nothing about not-found behavior, rate limits, or auth requirements.

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?

One front-loaded sentence with the verb, key, and return fields; the parenthetical field list is compact and every element earns its place. No preamble or filler.

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 compensates by enumerating the returned metadata fields, including the full-text source URL. It is nearly complete for a single-entity lookup; only edge-case behavior (invalid/unknown id) is unaddressed.

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?

Single parameter with 100% schema description coverage, including a worked example (11301409, Brown v. Board of Education), so the schema carries the semantics. The description only restates 'by its CAP id' and adds no format or validation detail beyond 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?

States a specific verb (Get) and resource (full metadata for a single case) and enumerates exactly which fields are returned, so the agent knows the payload shape before calling. It does not explicitly name or contrast the caselaw_search / caselaw_opinion_text siblings, which is the only thing keeping it from 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 implied rather than stated: use this when you already hold a CAP id and need the case's metadata. There is no explicit 'when not to use', no pointer to caselaw_search for finding an id or caselaw_opinion_text for the body, and no prerequisite that a CAP id must first be resolved.

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