place_actor

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

Annotations already declare destructiveHint=true, idempotentHint=false and readOnlyHint=false, so the danger profile is covered. The description adds genuine value with the single-item limit and the empty-cell precondition, but omits what the destructive operation affects, how expected_revision conflicts are handled, and whether sessions must be pre-attached.

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 short sentences, front-loaded with the action and followed by the one non-obvious format rule. There is no filler, though the brevity is arguably under-specification rather than tight editing on a 7-parameter mutation tool.

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 destructive, non-idempotent mutation with 5 required parameters, 0% schema coverage, and no output schema, the description is far too thin. Nothing explains the revision-check contract, the two session identifiers, or the failure modes an agent must anticipate before calling 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% across 7 parameters, so the description carries the full burden and largely fails: expected_revision (optimistic-concurrency token), rotation_index, browser_session_id, map_session_id, and item_id are never explained. Only color_linear_rgb gets meaning beyond the schema, via the 'linear RGB, not sRGB' note, and 'cell' is only implied by 'empty grid cell'.

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 verb and resource ('Place one ordinary item') plus a placement constraint ('empty grid cell'), which is enough to tell it apart from move_actors and delete_actors. However, the tool is named place_actor while the description says 'item', leaving a naming ambiguity an agent must resolve on its own.

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?

The description gives no when-to-use/when-not guidance and never names the obvious alternatives (move_actors for existing actors, select_actors, undo). The 'empty grid cell' phrase implies a precondition but does not say what happens if the cell is occupied or when an agent should prefer a different sibling.

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