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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds the informational scope of the payload (which categories of metadata come back), which matters because there is no output schema, but it says nothing about structure, volume, or whether the result is static.

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?

A single short sentence with no filler and the payload categories front-loaded. It is efficient, though the terseness leaves necessary context (catalog vs. per-block lookup) unaddressed rather than trimming redundancy.

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 no parameters and no output schema, the description carries the burden of explaining what comes back and how to use it, and it only partially does so — it names four categories but not the shape or whether items are identifiers usable in report_add_block. For a discovery/meta tool this is the minimum viable level of detail.

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?

The tool takes zero parameters, so there are no semantics for the description to explain; the baseline of 4 applies. Nothing in the description misrepresents the (empty) input contract.

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?

The verb 'list' and the returned categories (fields, groupings, dates, measures) are specific, but the object 'block configs' is ambiguous — it does not say whether this describes the fields of an existing block or enumerates the catalog of available fields/groupings for building one. Sibling tools like report_add_block and report_update_block are not referenced, so an agent gets no differentiation signal.

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?

There is no when-to-use guidance, no mention of prerequisites, and no comparison to alternatives such as report_preview_block or report_list_templates. The agent must infer that this is a discovery call to make before configuring a block.

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