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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is carried structurally; the description adds that the output is a text summary and that paragraph_ref injects a quoted paragraph into it. It does not discuss failure modes (invalid ID, unknown paragraph ref), which keeps it below 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?

Front-loaded purpose sentence, then return contents, then routing guidance, then per-argument notes — four short blocks with no filler. Every sentence adds information an agent needs to choose or call the tool.

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 an output schema present, listing return fields is a bonus rather than a requirement, and the sibling routing plus argument docs make the definition largely self-sufficient. The only shortfall is unstated behavior for unresolvable IDs or out-of-range paragraph_ref values.

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 carry the load and it does: authority_id is documented with a concrete format example ('uk.case.uksc.2019.38') and paragraph_ref is described as an optional numbered paragraph to quote. It stops short of clarifying accepted paragraph_ref syntax (bare number vs. prefixed form) or whether a bad ref errors or is ignored.

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 and resource ('Get full detail on a specific authority') scoped by canonical ID, then enumerates the returned fields. It explicitly contrasts itself with get_case_viewer, so the agent can distinguish it from siblings without opening either schema.

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?

Gives explicit workflow placement ('Use after resolve_citation or search_cases when you need the complete record as text') and names the alternative plus the condition selecting it ('For an interactive case viewer ... use get_case_viewer instead'). Both when-to-use and when-not-to-use are covered.

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