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

Beyond the annotations (readOnlyHint=false, idempotentHint=true, destructiveHint=false), the description discloses that the change is persisted immediately ('Saved when this runs'), that the user will see a reason on an approval card, and that re-adding an existing query moves it rather than duplicating — which is exactly what makes the idempotent hint meaningful.

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 purpose, then defaults, then the alternative tool, then the prerequisite — a logical order with no filler. It is dense (multiple clauses packed into two sentences), but every clause carries information an agent needs.

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 mutating, nested-parameter tool with no output schema, the description covers prerequisites, persistence semantics, placement defaults, and the competing tool. The only small gap is that it doesn't hint at what the call yields (e.g. the created panel identifier), which matters slightly more given there is no 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 coverage is 100%, so the baseline is 3; the description earns extra credit by explaining the interaction between the optional parameters: position inserts among query panels in reading order, gridPos overrides placement and sizing, and omitting everything gives a default 12x8 appended panel. That precedence is not stated anywhere in the schema.

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 ('Show an existing saved query on a dashboard as a panel') and immediately clarifies the one-to-many relationship. It is clearly distinguishable from create_<queryType>_query and remove_query_from_dashboard without opening either 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 routes the agent away from this tool when a new chart is needed ('To save a new chart, use create_<queryType>_query with dashboardId instead') and states a prerequisite ('Load the manage-dashboards skill ... first'). It also explains the default versus explicit placement behavior, so the agent knows which path to take.

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