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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=false, so the safety profile is covered. The description adds genuinely useful behavioral context beyond that: per-data-class freshness semantics with an explicit status vocabulary (fresh|aging|stale|CHECK-OFFICIAL-SOURCE) and a recheck_by date, plus corroboration and confidence signals, which tell the agent how to interpret and act on the payload.

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 with the identity and purpose in the opening clause, followed by one dense enumeration. It is efficient overall, though the long list of return fields partially duplicates what the output schema already carries.

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?

Given an output schema exists, the description need not detail return values, yet it supplies the interpretive layer the schema alone would not convey (what freshness statuses mean and the re-verify action). Combined with the clear when-to-use guidance and documented parameters, nothing needed to call it correctly is missing.

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 both parameters are documented there (cc as ISO alpha-2, pathway as optional single id). The description's 'Pass cc (+ optional pathway)' merely restates the required/optional split without adding format or scoping detail, so the 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?

States a specific resource (a country's pathway facts' provenance records) and a specific stance ('CITATION-FIRST', W3C PROV-O + Schema.org), and the enumerated return contents make it unmistakable that this is source/derivation metadata rather than the facts themselves. An agent can distinguish it from sibling fact-returning tools like get_country or get_recent_changes without opening any 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?

Explicitly says when to reach for it: 'Use this to CITE Mirabello data with a source + as-of date and to know when to re-verify.' That is a clear triggering condition tied to the sibling family. It stops short of naming an alternative tool or stating when NOT to use it (e.g. when you only need the fact, not the citation).

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