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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and a closed world, so safety is fully covered. The description adds the table allowlist ('main and data only') beyond that, but says nothing about row limits, cost, timeout, or result shape.

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 sentences, zero filler, and the constraint (read-only, table allowlist) is front-loaded before the workflow hint. 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 single-parameter, well-annotated tool this is nearly complete: scope, query shape, and the catalog-to-query workflow are all stated. With no output schema present, one more note on result shape or limits would close the remaining gap.

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?

Only one parameter, and schema coverage is 100%, so the schema already documents 'query' as a SELECT against main/data. The description reinforces the SELECT/WITH restriction but adds no syntax, dialect, or limit details beyond the schema. 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+resource (run a SQL SELECT) and immediately narrows scope to 'read-only SELECT (or WITH … SELECT) against tables main and data only'. No sibling tool competes for this task, and the query shape and target tables are unambiguous.

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?

Gives clear sequencing: 'Use after search_catalog + inspect_dataset to pull the time series for a known data.id / main_id', which tells the agent the prerequisite tools and when this tool is the right call. It stops short of naming an explicit alternative or a when-not case beyond the read-only restriction.

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