Would a grant reach a dataset

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is fully covered by structured data. The description adds only the useful hint that the result includes matched columns, which is somewhat redundant with the existing output schema; it says nothing about how tag matching is resolved or whether results are cached.

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 front-loaded sentence with zero filler; the core question comes first and the return hint second. It is tight, though arguably too terse for a tool taking a required nested-object expression.

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?

An output schema exists, so return values need no explanation, and annotations carry the mutation/safety story. However, for a tool with three required parameters including a nested tag-to-values object, the description provides no framing on how expressions are interpreted or what a negative result implies.

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%, so all three parameters (domain, table, expression) plus the nested tag-map shape are documented in the schema itself with examples. The description contributes no additional parameter meaning, which is the expected baseline when the schema does the heavy lifting.

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 description states a specific evaluation action ('would this tag-based grant expression reach this dataset') plus an output dimension ('which columns'), so an agent knows this is a hypothetical grant-resolution check rather than a lookup. It doesn't need to differentiate from siblings like find_datasets or get_dataset, which are unrelated operations, but it also never names them.

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 explicit when-to-use guidance, no prerequisites, and no mention of alternatives such as get_dataset for actually fetching an existing dataset. The question phrasing weakly implies a policy-authoring/verification context, but the agent must infer that entirely.

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