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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds the caller context (invoked by the artifact card) but says nothing about caching behaviour, which the forceRefresh parameter hints matters, or about what the call returns.

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, caller-context first and the routing warning second. Every clause carries information and nothing is repeated from the schema or annotations.

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 the description says not to call directly, this is close to sufficient, and the nested scope object is fully documented in the schema. What is still missing is any note on return shape or on when cached versus refreshed results are returned, which matters given forceRefresh.

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%, and parameters like fileId, chartPath and queryId are already documented with disambiguation notes in the schema itself. The description adds no parameter-level meaning beyond that, so the baseline 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 ('load the live numbers for a chart or report') and ties it to the artifact card. It does not spell out what the returned data looks like, but the action is unambiguous and distinguishable from the sibling it names.

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 says 'Not for direct use' and redirects to the alternative: 'call query_insights_report to query a report.' That is a clear when-not plus a named substitute, leaving no inference needed.

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