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

With no annotations, the description carries the full load and does so: plan gating with the exact error code KEY_PLAN_001 and no charge, the empty-list case for never-queried parcels, the always-null cadastral value, the 30-day snapshot cap, and the definition of change_pct. That is exactly the behavior an agent cannot get from the schema.

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 mostly front-loaded, with the plan/error caveat leading so an agent does not waste a call. A few clauses are compressed to the point of terseness (the opening colon construction), but no sentence is filler.

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 tool with no annotations and no output schema, the description covers return content reasonably (snapshots, area, land use, change_pct, null cadastral value). It does not say whether the snapshot list is bounded or what the full record shape looks like, which leaves a modest gap for a read tool without an output schema.

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 100%, so both reference and country are already documented, including the auto-detect behavior on country. The description restates the supported country list but adds no new semantics for the parameters themselves; 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 (parcel snapshots as reported by the official cadastre) with the fields carried (area, land use), and its cadence (at most one snapshot every 30 days). This clearly separates it from get_parcel, which returns current state rather than history.

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 a decisive precondition: history only exists for parcels previously looked up via get_parcel, so an unqueried parcel returns an empty list — that steers the agent away from calling this cold. It also flags the paid-plan requirement. It stops short of explicitly naming get_parcel as the prerequisite call to run first.

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