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

Annotations already flag destructiveHint and idempotentHint, but the description adds what they cannot: that human strokes are also destroyed, that a board-clear is broadcast to connected participants, and that get_board_state becomes empty. That is exactly the blast-radius context an agent needs before an irreversible wipe.

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?

The destructive scope is front-loaded in the first clause, and the em-dash framing ties it to the human toolbar action for instant recognition. The closing toolkit sentence is longer than strictly necessary but does real routing work, so it mostly earns 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 an output schema present and rich annotations, the description needn't explain return values, and it covers the destructive scope, broadcast side effect, and credential prerequisite via schema. Only failure or permission-denied behavior on a locked pond is left implicit.

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 roomId, senderId, and agentSecret are fully documented in the schema, including the locked-pond credential requirement. The description adds no parameter-level meaning beyond that, 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 verb and resource (clear the board), plus the critical scope qualifier in caps: FOR EVERYONE. It also explicitly distinguishes itself from the sibling tools it could be confused with (draw_on_board, undo_board, remove_strokes) by naming each one's role.

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 final sentence maps the sibling tools to their jobs, so an agent can infer that undo_board or remove_strokes is the right call when it only wants to retract its own work. There is no explicit "do not use this when..." exclusion, which keeps it just short of a 5.

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