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

Annotations already declare readOnlyHint and openWorldHint=false, and the description is consistent with the closed EU-scope set. It adds real value by disclosing the shape of each result (verified URL, machine-readability, reuse licence, 'where known' signalling possible gaps), which matters since there is no output schema. It does not cover ordering, volume, or how 'verified' was established.

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?

Two sentences, front-loaded with the scope and payload, with no digressions. The closing 'Free, read-only' is largely redundant with the readOnlyHint annotation and is the one phrase that does not earn its place.

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 carries the burden of describing returns and does so adequately by naming URL, machine-readability, and licence fields. It stops short of the entry structure or typical result count, but an agent has enough to select and call it correctly.

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% and the single parameter already documents the EU/ISO-code convention and the omit-for-all behavior. The description only echoes the same scope ('a country or the EU') without adding format or edge-case detail, so baseline 3 applies.

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?

Names a specific verb and resource ('List official legal sources') plus the exact scope ('for a country or the EU') and enumerates what the entries are (legislation portals, registers, APIs, open data, authorities). This is clearly a discovery/catalog tool, distinguishable from siblings like find_law (search law text) or get_law_link (resolve a link).

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 only implied: an agent can infer it should call this to discover where a country's legal data lives before fetching laws. The description never states when not to use it or names find_law/get_law_link as the alternatives for actual document retrieval, so routing depends on inference from sibling names.

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