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

With annotations already covering read-only, idempotent and closed-world behaviour, the description adds substantial non-redundant context: account linking requirement, per-ECLI monthly credit cost, pagination semantics (next_offset null on the last page), SHA-256 version verification on subsequent pages, and the caveat that absence from the collection does not mean the ruling doesn't exist.

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?

Dense and essentially waste-free, with every clause adding operational information. It is slightly back-loaded: the actual purpose (returns a ruling by ECLI) arrives after the billing/account sentence, which is arguably not the first thing an agent needs.

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 paginated read with no output schema, the description covers call prerequisites, cost, paging, and version verification, and even references output fields (next_offset, source_sha256). The main residual gap is how a not-found ECLI is surfaced (error vs empty result), though the closing caveat gestures at it.

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 0%, so the description has to carry the load, and it largely does: id is tied to ECLI retrieval, offset is framed as page continuation, and expected_sha256 is explained as verifying the source version returned as source_sha256 on follow-up pages. It stops short of describing the regex format or that offset defaults to 0.

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 clearly states a specific verb and resource: it returns a court ruling from the collection based on an ECLI, delivered as consecutive text pages. That distinguishes it from scan_contract, make_memo and the dossier tools. It does not, however, explicitly name sibling 'search' as the way to find an ECLI when you don't already have one, so the boundary is only implicit.

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 useful usage context — account linking required outside the fixed demo, one source credit per unique ECLI per month — but never states when to choose fetch over search, or what prerequisite (possessing an ECLI) must hold. Usage is implied by the ECLI-based contract rather than spelled out.

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