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

Annotations only say readOnlyHint=false / destructiveHint=false / openWorldHint=false; the description adds real substance on top: coin costs per building type (100/120/140/160), a one-plot-per-owner limit, that placed goods go 'back to storage' on put_away, and that plots are a showing/second-home surface. It does not say whether 'remove' refunds the building cost — worth noting since destructiveHint=false while 'remove: takes the building down' reads destructive.

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?

It is front-loaded with the defining concept, but everything else is one dense paragraph of sentence fragments covering 14 actions with no separation, so scanning for a specific action is slow. Nearly every clause does carry information, so it is dense rather than padded, but the lack of structure costs it.

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?

All 14 actions are at least glossed, which is substantial coverage for a multiplexed tool, and the safety profile is covered by annotations. Missing: what any action returns, whether buy/build fail on insufficient coins or a second plot, and any mention of the 'key' auth parameter. The pointer to /skill/commons pushes that detail out of band.

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 baseline is 3. The description's per-action glosses on 'what' are essentially a verbatim restatement of the schema's own 'what' description, and the optional 'key' parameter is never mentioned in the description at all. No formatting syntax or edge cases are added beyond what the enum and property descriptions already carry.

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?

Opens with a concrete framing ('owner-only land, bought with coins, one each, a second home for showing') and then names every action with a specific verb+object gloss (buy a plot number, build a pavilion, place a garden thing). An agent can tell this is the land-ownership tool and not, say, the catalog or inbox tool. It stops short of 5 because the run of verbs (go, look, name, sign) collides with sibling tools of the same name and the description never states which namespace wins.

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: each action's gloss hints at when you'd reach for it ('list: what's for sale and at what price'), and the closing 'Chapter: plazmi://skill/commons' points elsewhere for depth. There is no explicit when/when-not and no named alternative among the many siblings (build, go, look, sign_in, make) that overlap these actions.

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