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

Annotations declare readOnly/idempotent/non-destructive, and the description still adds real value beyond them: SCTS judgments are PDF-only, the response shape (verified URL, HTTP status, content-type, size, text_extracted: false), and the catalog-wide absence of a PDF-text pipeline. That is exactly the behavioral context 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?

Three tight sentences, front-loaded with what the tool does, then inputs, then the critical limitation. The clause about no PDF-text pipeline existing in the catalog is slightly redundant against the text_extracted: false statement but is defensible as a routing hint.

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 fully compensates by enumerating the returned fields and stating the non-extraction limitation. An agent has everything needed to call this correctly and to know what to do next (fetch pdf_url).

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 the baseline is 3, and the description goes beyond it by clarifying that document_link must be passed exactly as returned by search (relative /media/... or absolute URL) and that query is the lookup fallback when no link exists. It adds meaning but not format-level detail beyond the schema's example.

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 ('Resolve a Scottish Courts judgment PDF and confirm it is actually reachable') and distinguishes itself from the sibling search_scottish_judgments by casting itself as the verification step after search. An agent can tell immediately what it produces.

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?

Explicitly names the two input paths (pass document_link exactly as returned by search_scottish_judgments, or a case name/citation) and adds a clear exclusion: it does not extract text, and the agent should fetch pdf_url to read the judgment. The when-to-use alternative is spelled out.

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